BAW Code of Practice - Bundesanstalt für Wasserbau (BAW) · BAW Code of Practice: ... Annex 5.6.2-1: Permeable armour layers comprising riprap placed on a geotextile, with an impermeable

BAW Code of Practice

Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways (MAR) Issue 2008

BAW Codes of Practice and Guidelines

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prior permission of the publisher: © BAW 2008

Karlsruhe · December 2008 · ISSN 2192-9807

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008

„MAR“ Working group

(April 2006 – December 2008)

Members:

BARTNIK, Wolfgang Dipl.-Ing., Wasserstraßen-Neubauamt Datteln

CONRADI, Stefan Dipl.-Ing., Wasser- und Schifffahrtsdirektion Ost, Magdeburg

FISCHER, Uwe Dipl.-Ing., Bundesministerium für Verkehr, Bau, und Stadtentwicklung, Bonn

FLEISCHER, Petra Dipl.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

HEIBAUM, Michael Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

HOLFELDER, Tilman Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

KAYSER, Jan Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe (Leiter der AG)

LIEBENSTEIN, Hubert Dipl.-Ing., Bundesanstalt für Gewässerkunde, Koblenz

NULLE, Undine Dipl.-Ing., Wasser- und Schifffahrtsamt Berlin

OSTERTHUN, Manuela Dr.-Ing., Wasser- und Schifffahrtsdirektion Mitte, Hannover

POHL, Martin Dr.-Ing., Bundesanstalt für Wasserbau, Hamburg

SÖHNGEN, Bernhard Prof. Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

SOYEAUX, Renald Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

STEIN, Jürgen Dr.-Ing., Bundesanstalt für Wasserbau, Karlsruhe

THYSSEN, Heinz-Jakob Dipl.-Ing., Wasser- und Schifffahrtsdirektion West, Münster


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I

Table of Contents Page

1 Preliminary Remarks 1

2 Terms and Definitions 2

3 Boundary Conditions for Standard Construction Methods 4 3.1 General 4 3.2 Types of vessel and hydraulic loads 5 3.3 Waterway cross-sections 7 3.4 Ground conditions 8

4 Revetment Components 10 4.1 Armourstones 10 4.2 Grout 11 4.3 Filter layers 11 4.4 Separation layers 11 4.5 Impervious lining systems 11 4.5.1 General 11 4.5.2 Flexible lining systems 12 4.5.3 Inflexible lining systems 12

5 Standard Methods of Construction 12 5.1 General 12 5.2 Armour layers 14 5.2.1 Permeable armour layers comprising riprap 14 5.2.2 Permeable armour layers comprising partially grouted armourstones 16 5.2.3 Impermeable armour layers comprising fully grouted armourstones 17 5.3 Toe protection 18 5.4 Flexible linings 20 5.5 Freeboard height 20 5.6 Selection of a standard method of construction 20 5.6.1 General 20 5.6.2 Requirement for an impervious lining 21 5.6.3 Soil classification 22 5.6.4 Requirement for a filter or a separation layer 22 5.6.5 Selection of an armour layer 23

6 Other Methods of Construction 23 6.1 General 23 6.2 Revetments in combined rectangular-trapezoidal (KRT) profiles 24 6.3 Impermeable erosion-resistant pavements 24


7 Vegetation Cover in Standard Methods of Construction 25 7.1 General 25 7.2 Permeable armour layers comprising riprap or partially grouted armourstones as described in

sections 5.2.1 and 5.2.2 respectively 26 7.3 Impermeable armour layers comprising fully grouted armourstones as described in

section 5.2.3 27 7.4 Guidance on vegetation cover on flexible linings 27

8 Guidance on Invitations to Tender, Execution of the Works, Quality Control and Maintenance 27 8.1 General 27 8.2 Invitations to tender 28 8.2.1 General 28 8.2.2 Armour layer 29 8.2.3 Underlayers 30 8.2.4 Minimum requirements for secondary tenders 30 8.3 Execution of the works 31 8.4 Quality assurance 32 8.4.1 General 32 8.4.2 Depth measurements for quality assurance 33 8.5 As-built documents 33 8.6 Guidance on maintenance 34

9 Literature 35

List of Tables

Table 3.2-1: Dimensions of ship types 5

Table 3.3-1: Geometry of the standard canal profiles N.B: Only the first bank is considered

for the revetment design. 8

Table 3.4-1: Characteristic soil parameters for soil types B1 to B5 9

Table 4.1-1: 50 %-values for the standard size classes for riprap armour layers 11

Table 5.1-1: Void ratio of armourstone armour layers as a function of the method of installation

(based on depth measurements taken at the highest points of the armourstones) 13

Table 5.2.1-1: Stone diameters, stone weights and size classes required for standard profiles

approved for all types of inland waterway vessels (ES, GMS, SV, üGMS)

for a range of densities (2300 – 3600 kg/m3) 15

Table 5.2.1-2: Recommended armour layer thicknesses (riprap) for slope and bottom revetments,

taking account of the soils specified in 3.4 16

Table 8.2.1-1: Documentation to be provided on submission of a tender 29

II


List of Figures

Figure 3.2-1: Example of the most unfavourable position of a large self-propelled barge or

push-tow unit at full draught in a T-profile 7

Figure 4.1-1: Definition of the design values G50, shown here for class LMB5/40 10

Figure 5.2.1-1: Diagram of the cross-section of a permeable armour layer of riprap 14

Figure 5.2.2-1: Diagram of the cross-section of a permeable armour layer comprising partially

grouted armourstones 17

Figure 5.2.3-1: Diagram of the cross-section of an impermeable armour layer comprising fully

grouted armourstones 18

Figure 5.3-1: Design of the toe protection 19

Figure 5.6-1: Criteria for the selection of an impermeable or permeable revetment 22

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IV

List of Annexes

Annex 3.1: Principles of hydraulic design in accordance with /GBB/ 38

Annex 3.2.1: Hydraulic loads at 97 % vkrit for standard T-profiles 40

Annex 3.2.2: Hydraulic loads at 97 % vkrit for standard RT-profiles 41

Annex 4.1-1: Guidance on how to determine the mean stone size, D50, or

the mean stone weight, G50 42

Annex 4.1-2: Cumulative curves for armourstones - classes LMB10/60, LMB5/40, CP90/250 43

Annex 5.2.1-1: Permeable armour layers comprising riprap – Recommended

thicknesses, dD, of armour layers for slope and bottom protection systems 44

Annex 5.2.1-2: Permeable armour layers comprising riprap - Documentation of the armour layer

thickness, dD, calculated for slopes (with a geotextile) 46

Annex 5.2.1-3: Permeable armour layers comprising riprap – Calculated minimum thicknesses 47

Annex 5.2.2-1: Permeable armour layers comprising partially grouted armourstones -

Recommended thicknesses, dD, of armour layers for slope and bottom protection

systems (with a geotextile) 48

Annex 5.2.2-2: Permeable armour layers comprising partially grouted armourstones -

Documentation of the calculated armour layer thickness, dD, for slopes

(with a geotextile) 49

Annex 5.2.3: Impermeable armour layers comprising fully grouted armourstones placed on

a geotextile – Required armour layer thickness, dD, against buoyancy 50

Annex 5.6.2-1: Permeable armour layers comprising riprap placed on a geotextile, with an

impermeable lining – Required armour layer thickness, dD, against buoyancy 51

Annex 5.6.2-2: Permeable armour layers comprising partially grouted armourstones placed on

a geotextile, with an impermeable lining – Required armour layer thickness, dD,

against buoyancy 52


1 Preliminary Remarks

The following Code of Practice deals with standard methods of constructing bank and bottom protection

systems for inland waterways which may be used under defined boundary conditions without the need for

verification by calculation.

The first edition of the Code was published in 1993. Considerably more is now known about how to exe-

cute revetments, the actions on such structures and their stability. In addition, the relevant rules and

standards have either been revised or rewritten. A thorough revision of the Code was therefore necessary

and the revised version is now available as the present 2008 edition.

The standard methods of construction are based on experience in the construction and maintenance of

revetments and on engineering design rules. The latter are to be found in the Principles for the Design of

Bank and Bottom Protection for Inland Waterways /GBB/ which was also published by the Federal Wa-

terways Engineering and Research Institute.

The standard construction methods have been drawn up both with present-day vessels and future ship-

ping in mind, taking account of the increase in the number of large Rhine barges (self-propelled barges).

The principal geometries considered are the trapezoidal profile (T-profile) and the rectangular-trapezoidal

profile (RT-profile) for Class Vb waterways in accordance with the Directives for the Standard Cross-

Sections of Canals for Inland Shipping /RiReS/, with a blockage ratio, n, greater than 5.3. Application of

the standard methods of constructing revetments to smaller canals with the same blockage ratio will gen-

erally result in a conservative design, even though the ships, draughts and bank distances are corre-

spondingly smaller than in standard profiles. A separate hydraulic design is generally required if

ungrouted revetments are installed on cross-sections with lower blockage ratios, such as those intended

for one-way traffic, as the loads due to the return current, bow thrusters and, for water depths less than

4 m, to the propeller wash caused by the main propulsion units may be greater than those in standard

profiles.

A value of 97 % of the critical ship speed has been specified as the design speed. It takes economic con-

siderations into account, including the behaviour of shipping and the dimensioning of the revetment.

Individual revetment designs in accordance with the Principles for the Design of Bank and Bottom Protec-

tion for Inland Waterways /GBB/ are required if the geometrical, hydraulic and geotechnical boundary

conditions differ from those on which the standard designs are based. The boundary conditions under

which the methods of construction described in this Code of Practice apply are detailed in section 3 to

enable designers to ascertain whether an individual design is necessary.

All standard methods of construction are technically equivalent unless further restrictions are explicitly

stated. The choice of construction method will be based on technical and economic criteria.

The Codes of Practice "Use of Geotextile Filters on Waterways" /MAG/ and “Use of granular filters on

waterways” /MAK/ apply to the design of filters required for the standard methods of construction. In addi-

tion, the Code of Practice “Use of Cement Bonded and Bituminous Materials for Grouting of

Armourstones on Waterways” /MAV/ applies to grouted revetments. Information on the execution of lin-

ings is given in the “Recommendations for the use of lining systems on beds and banks of waterways”

1


/EAO/. The Supplementary Technical Contract Conditions – Hydraulic Engineering for Embankment and

Bottom Revetments (Section 210) /ZTV-W 210/ apply to the tendering procedure and to execution. In all

cases, the latest versions of the above publications shall apply.

2 Terms and Definitions

Some of the principal terms used in this Code of Practice are explained below. Other important terms are

defined in /GBB/.

Armour layer: Upper erosion-resistant layer of a bank or bottom revetment. In standard methods of con-

struction the armour layer consists of a layer of armourstones.

Armour layer thickness: Thickness of the armour layer dD, measured perpendicular to the lower or up-

per edge of the layer (without a filter or impervious lining).

Bank and bottom protection (system): Permeable or impermeable revetment installed on a waterway

to ensure that the geometry of the cross-section is maintained.

Blockage ratio: Ratio, n, of the cross-sectional area of a waterway at a particular water level, A, (which

affects the return flow) to the cross-sectional area, of the submerged midship section of a vessel, AM (n =

A/AM,)

Bow-heavy: Used to describe a ship laden such that the bow is immerged to a greater depth than the

stern. In this case, it is the bow dimensions that are decisive for the design of bank and bottom revet-

ments.

Critical ship speed, vkrit: Speed of a ship in shallow water or in a canal at which the water displaced by

the vessel is prevented from flowing fully in the opposite direction to the ship and past its stern. The tran-

sition from subcritical to supercritical flow begins (the Froude number in the narrowest cross-section adja-

cent to the vessel being equal to 1). In general, displacement craft cannot exceed vkrit. Any attempts by

displacement craft to travel faster than vkrit, e.g. by increasing the driving power, generally result in even

higher return flow velocities and in a greater drawdown than at vkrit, causing the speed of the vessel over

ground to diminish and/or the vessel to be drawn towards the bed of the river or canal.

Dynamic underkeel clearance: Difference between the water depth and the draught of a moving ship

(sailing draught). The latter is the sum of the draught and the squat.

Excess pore water pressure: Water pressure in the pores of a soil that exceeds the hydrostatic pore

water pressure. Excess pore water pressure occurs when the volume of the pore water is prevented from

increasing (if the pore water pressure changes) or when the volume of the granular structure is prevented

from decreasing (if there are changes in the total or effective tension in the granular structure). It is

caused, amongst other things, by rapid water level drawdown. As a result, the pressure in the subsoil will

be higher than that at the water/soil interface.

Filter: The purpose of a filter (comprising a geotextile or aggregates (granular filter)) is to retain soil under

all possible hydraulic conditions (mechanical filtration stability: protection against erosion). At the same

time, it must permit the passage of groundwater without any rise in the seepage line (hydraulic filtration

stability).

2


Freeboard: Distance between the highest possible water level (upper operating water level, plus any

safety margin required) and the lowest point on the bank that must not be overtopped.

Grout: Construction material applied as a liquid and which hardens over time, the setting period being

dependent on the material.

Hydraulic loading: The interaction between a ship and the waterway causes a displacement flow around

the ship’s hull which is accompanied by the bow wave, the generation of diverging waves at the bow with

a short wave period, water level drawdown adjacent to the ship, the generation of transversal stern waves

with a short wave period and a slope supply flow which restores the surface of the water to its undis-

turbed level. The sequence of bow waves, water level drawdown and transversal stern waves corre-

sponds approximately to the length of the ship and is known as a primary wave (primary wave system).

The waves with short wave periods generated at the bow and stern are referred to as secondary waves

(secondary wave system).

Lane: Width required by a moving ship within a channel for nautical and hydrodynamic reasons.

Manoeuvring area: Area of a canal or waterway in which ships change course, slow down or accelerate,

including turning basins, mooring points, lock waiting areas and loading/unloading facilities.

Minimum armour layer thickness: In addition to the thickness of the armour layer obtained in the geo-

technical design calculations, a certain minimum thickness is required to take account of impacts by ship-

ping, the stability of the layer of dumped armourstones and the variations in its uniformity, anchor cast,

the type of filter used or other technical aspects. (For values, see /GBB/, sections 6.9 and 6.11, and

/Kayser 2005/). The greater armour layer thickness shall apply.

Partial/full grouting: Partial grouting consists of partially filling the voids between the armourstones with

grouting material, full grouting of filling the voids completely with grouting material.

Primary wave: Hydraulic loading.

Revetment: Overall structure of a bank and bottom protection system including the armour layer, the filter

and, if necessary, an impervious lining with a separation layer, but not the underlayer, if used. Permeable

revetments permit unhindered water exchange between the subsoil and the waterway. They generally

comprise an armour layer placed on a filter. Impermeable revetments prevent the exchange of water

between the waterway and the subsoil. They may comprise a permeable armour layer placed on an im-

pervious lining, the two being separated by a geotextile separation layer, or an impermeable armour layer

placed on a geotextile separation layer.

Secondary wave: Hydraulic loading.

Separation layer: Separation layers prevent the mixing of different granular layers and erosion. In con-

trast to filters, their hydraulic filtration stability is of minor importance (e.g. non-cohesive soil on soft to

pulpy ground, armourstones on a clay liner, inflexible lining on erosion protection). At the same time,

separation layers may promote the self-healing of defective impervious lining systems.

Stability of the armour layer: The individual stones in riprap armour layers must interlock in order to

ensure that the rock armour is stable. A minimum thickness is therefore required, irrespective of the de-

3


sign calculations (for values, see /Kayser 2005/). Interlocking stones are a prerequisite for the use of the

equations for the sizing of individual stones given in /GBB/.

Standard method of construction: Standardized construction method which can be applied under cer-

tain specified boundary conditions without separate verification by calculation.

Stern-heavy: Used to describe a ship laden such that the stern is immerged to a greater depth than the

bow. In this case, it is the stern dimensions that are decisive for the design of bank and bottom revet-

ments. Generally speaking, ships are stern-heavy when sailing empty or with ballast at the stern (to en-

sure that the propeller is completely submerged).

Toe protection: Lower part of a slope revetment in the absence of a bottom revetment.

Vegetation cover: This may consist of one or both of the following:

(1) Grasses and herbs native to the locality (or legumes for a first soil improvement) sown on the bank

slopes. Vegetation may also become established as a result of natural seed dispersal, plant material

being deposited by currents or waves, hay containing ripe seeds being spread over the slopes or by

planting sods or depositing soil containing seeds.

(2) Woody plants (including cuttings), reeds or herbaceous perennials planted on the bank slopes.

Water level drawdown/drawdown velocity: Vessels in motion cause the water to flow around them in a

particular way which results in the lowering of the water level adjacent to the vessel. Drawdown occurs

along the entire length of the ship. The water level drawdown at the banks of the waterway and the asso-

ciated drawdown velocity are relevant for design.

Zone of fluctuating water levels: Zone on a canal slope which is subjected to the highest hydraulic

loads (bow and stern waves, positive surge and drawdown due to lockage operations, wind waves). In the

context of this Code of Practice, the zone of fluctuating water levels extends from 1.0 m below the lower

operating water level, BWu, to 0.7 m above the upper operating water level, BWo.

3 Boundary Conditions for Standard Construction Methods

3.1 General

The standard construction methods apply when certain boundary conditions in respect of

the types of ships using a waterway (see section 3.2)

the waterway cross-sections (see section 3.2) and

the ground conditions (see section 3.4)

are satisfied. They are based on the Principles for the Design of Bank and Bottom Protection for Inland

Waterways /GBB/.

Certain assumptions on the characteristics of the ships and the armourstones are made to facilitate the

calculation of the hydraulic actions and for design purposes. The parameters subsequently selected are

listed in Annex 3.1.

4


Armourstones of various size classes and densities as defined in section 4.1 and grouting materials as

defined in 4.2 are taken into account.

Geotextiles or granular filters in accordance with section 4.3 may be used as filters.

The impermeable linings used in the standard methods of construction may be tried-and-tested flexible or

inflexible linings as defined in section 4.5, combined with a separation layer as defined in section 4.4.

3.2 Types of vessel and hydraulic loads

The standard methods of construction are based on common types of inland waterway vessel with the

standard dimensions shown in Table 3.2-1, i.e.:

Europe ships (ES)

large self-propelled barges (GMS)

push-tow units (SV)

very large self-propelled barges (üGMS).

These types of vessel cover the usual spectrum of ships to be found on Class Vb inland waterways. The

cargo of fully laden ships (with the maximum draught permitted for canals) is usually evenly distributed

over the vessel. Empty ships or ships sailing with ballast are assumed to have a stern-heavy trim. It

should be noted that the coefficient CH, which reflects the influence of the type of ship, the degree of

loading, the trim and the water surface gradient, is considered in relation to the ratio of draught to water

depth, T/h, (see Annex 3.1) in the basic calculations performed here.

Table 3.2-1: Dimensions of ship types

Draught

T [m]Fully laden* Empty Type

Length

L [m]

Width

B [m]

Bow/stern Bow Stern

Europe ships (ES) 85 9.50 2.50 0.70 1.40

Large self-propelled

barges (GMS) 110 11.45 2.80 0.80 1.60

Push-tow units (SV) 185 11.45 2.80 0.60 1.60

Very large self-propelled

barges (üGMS) 135 12.00 2.80 0.90 1.80

*max. permissible draught for canals

Certain types of vessel such as tugs or pusher craft sailing alone are not considered as they are generally

seen quite rarely on inland waterways. However, the potentially greater loads occurring in canal sections

in which such craft account for a significant proportion of vessels must be taken into account as specified

in /GBB/, in particular where such vessels can be assumed to travel at speeds close to the critical ship

5


speed, similar to the types of vessel referred to above. Such loads result from the possible superpositions

of bow and stern waves or of primary and secondary waves which are not relevant for the types of vessel

in standard canals shown in Table 3.2-1. Higher loads must also be taken into account if the waterways

are frequently used by very large motor yachts assumed to travel close to sliding speed.

Loads caused by typical recreational craft are generally lower than those caused by the types of vessel

referred to in Table 3.2-1 and are covered by the standard methods of construction. The greater run-up

height of secondary waves, in particular those due to recreational craft, is taken into account when the

freeboard is specified (see section 5.5).

It is assumed that only ship-induced currents in the waterway are relevant for design purposes. The ship

speed over ground may be taken as being equal to the ship speed through the water.

As recommended in /GBB/, a ship speed of 97 % of the critical speed is assumed for design purposes.

The value corresponds to the typical measured maximum ship speeds that have been observed irrespec-

tive of the permissible ship speeds. It reflects the behaviour of inland navigation vessels on canals. Cases

in which the critical ship speed is reached or exceeded only occur very rarely and are locally limited so

that they do not constitute standard design situations.

Tables with the most important hydraulic loads for the above ship speeds in trapezoidal and rectangular-

trapezoidal profiles are given in Annex 3.2. The ship speeds shown in the tables may be lower than the

permissible ship speed, vzul, stated in the German Regulations for Navigation on Inland Waterways

/BinSchStrO/ if the blockage ratio (ratio of the waterway cross-section to the cross-section of the ship) is

low, e.g. in the case of large self-propelled barges in T-profiles. The opposite case, in which the values of

97 % of the critical ship speed, vkrit, exceed the permissible ship speed, vzul, can occur when the blockage

ratio is high (ships with small cross-sections). Revetment designs as specified in /GBB/ are required for

ship speeds other than 97 % of the critical ship speed.

The ship’s position is taken to be the most unfavourable path of a fully laden vessel travelling close to the

bank. In the case of T-profiles the ship is assumed to be travelling 1 m over the toe of the slope at the

edge of the navigation channel in accordance with the “Directives for the Standard Cross-Sections of

Canals for Inland Shipping” /RiReS/. An example of a fully laden large self-propelled barge is shown in

Figure 3.2-1. The same position has been assumed for unladen vessels on the basis of field tests.

In the case of RT-profiles it has been taken into consideration that the available width of the navigation

channel at the level of the relevant draught of the moving vessel is greater than for T-profiles. Further-

more, the distance to the design bank in RT-profiles is taken to be 1.5 m greater than in T-profiles in

keeping with field investigations which revealed greater bank distances in the former.

6


Figure 3.2-1: Example of the most unfavourable position of a large self-propelled barge or push-tow unit at full draught in a T-profile

The greatest hydraulic loads usually occur when single vessels are travelling along a waterway. It can be

assumed that the loads will be lower when vessels pass or overtake each other owing to the reduced

speeds and changes in the blockage ratios that occur in such situations.

Exceptions are loads due to the propulsion and steering units of ships which are greater when ships pass

each other than when craft are travelling alone. However, they do not generally reach values that would

be relevant for design.

Evaluations of recent measurements of propeller wash at the bottom of waterways have shown that mod-

ern large self-propelled barges – single-screw vessels, in particular – generate wash velocities of around

3.0 m/s close to the bottom of a waterway when sailing at the permissible dynamic underkeel clearance

on reaches. In this case, the scour depths caused by individual ships are likely to be less than 0.2 m if the

revetment comprises riprap of class LMB5/40 with a density of 2650 kg/m3. A value of 0.2 m, which is the

maximum scour assumed to occur, is locally acceptable. Greater, accumulated scour depths are unlikely

on reaches as local increases in the propeller wash loads will not always occur at the same points.

Theoretical calculations assuming extreme values performed in accordance with /GBB/ and measure-

ments performed for large ships have shown that propeller wash velocities of up to around 5.0 m/s may

occur close to the bottoms of waterways during manoeuvring operations. The associated scour depth in a

bed revetment comprising riprap of class LMB5/40 would be equal to the thickness of the armour layer.

Modified construction methods are therefore required for canal sections in which manoeuvring operations

are frequent. For example, a greater water depth could be selected or a partially grouted armour layer

installed.

3.3 Waterway cross-sections

The standard methods of construction apply to the two principal types of standard canal profile, i.e.

the trapezoidal profile (T-profile) and

7


the rectangular-trapezoidal profile (RT-profile).

Details of the dimensions are laid down in the “Directives for the Standard Cross-Sections of Canals for

Inland Shipping” /RiReS/. The basic geometry of each profile is summarized in Table 3.3 1.

Table 3.3-1: Geometry of the standard canal profiles N.B: Only the first bank is considered for the revetment design.

Slope inclination

1 : m Width at water level

bWS

Water depth

h 1st bank 2nd bank

Profile

[m] [m] [-]

T 55.0 4.00 1:3 1:3

RT 48.5 4.00 1:3

A further profile, known as the combined rectangular-trapezoidal profile (KRT-profile), is also in use. The

sides of the KRT-profile below water-level are vertical while those in the zone of fluctuating water levels

are sloped /RiReS/ (see section 6.2 for guidance on execution).

The standard methods of construction are based on the lower operating water level, BWu, which is re-

garded as representative and at which the assumed canal water depth is 4 m. Greater depths result in

lower loads at the same ship speed and are therefore generally speaking not relevant for design.

3.4 Ground conditions

The armour layer thickness required to ensure the local stability of a slope is significantly influenced by

the type of in-situ ground beneath the revetment /GBB/. The standard methods of construction described

in section 5 apply to five different types of soil:

B1: sands and gravels

B2: sands

B3: silty sands and gravels

B4: silts, highly silty sands and gravels

B5: cohesive soils

Apart from the shear strength, the permeability of the soil is of particular relevance to revetment design.

The excess pore water pressure beneath a revetment due to water level drawdown close to the slope

caused by passing ships, and its destabilizing effect on the revetment and the subsoil, are inversely pro-

portional to the permeability of the in-situ soil. However, this only applies to cohesionless soils (B1 to B4).

8


If a soil permanently retains an effective cohesion, c‘k, of at least 3 kPa, even under water, it may be as-

sumed that the local stability of permeable revetments (on cohesive soil, type B5) will not generally re-

quire verification in accordance with section 7.2 of /GBB/. The minimum armour layer thicknesses apply in

such cases. The standard methods of construction do not apply if the effective cohesion is 0 < c‘k < 3

kPa, and in such cases revetments must be designed in accordance with /GBB/. For conservative de-

signs, a type B4 soil can be assumed if the cohesion is 0 < c‘k < 3 kPa and the permeability is 5·10-6 = kk

= 1·10-6 m/s.

The mechanical soil parameters of soil types B1 to B5 on which the standard profiles are based have

been summarized in Table 3.4 1 to facilitate classification of the in-situ soil. The classification is based on

the fines content (d5, d10, d15), also shown in Table 3.4-1, which is the main factor determining the charac-

teristic permeability, kk, of the soil. The design calculations for the standard methods of construction were

performed with the lower values of the coefficient of permeability shown in Table 3.4-1.

Table 3.4-1: Characteristic soil parameters for soil types B1 to B5

Soil Descrip-tion

Coefficient of per-meability

Effectiveangle of friction

Effective cohesion

Wet specific weight

Specific weight under

buoyancy

Particle diameter di at i-% passing sieve

kk k' ck' k k' d5 d10 d15

[m/s] [°] [kN/m²] [kN/m³] [kN/m³] [mm] [mm] [mm]

B 1 Sands

and gravels

kk ≥ 5·10-4 35.0 0 19 11 ≥ 0.2

B 2 Sands 5·10-4 > kk ≥ 5·10-5 35.0 0 19 11 ≥ 0.07

B 3

Silty sands and

gravels

5·10-5 > kk ≥ 5·10-6 32.5 0 18 10 ≥

0.002 ≥ 0.02

B 4

Silts, highly silty

sands and

gravels

5·10-6 > kk ≥ 1·10-6 30.0 0

(0<ck'<3)

18 10 ≥

0.002≥

0.02

B 5 Cohesive

soils 1·10-6 > kk < 30.0 ck' ≥ 3

< 0.002

< 0.02

9


4 Revetment Components

4.1 Armourstones

The requirements for armourstones used in revetments are laid down in the European Standard EN

13383-1 - Armourstone, Part 1: Specification /DIN EN 13383-1/. The current edition of the Technical Sup-

ply Conditions for Armourstones /TLW/ also applies.

EN 13383-1 specifies various standard size classes with different resistances to hydraulic actions. Small

armourstones are defined by the sieve perforation size, D, (size of the square perforations) and are re-

ferred to as class CPx/y (Coarse Particle, x being the lower class boundary [mm] and y the upper class

boundary [mm]). The larger classes are defined by the weight, G, of the stones as light gradings LMx/y

(Light Mass, x = lower class boundary [kg], y = upper class boundary [kg]) or heavy gradings HMx/y

(Heavy Mass). The stones used in armour layers for revetments on inland waterways generally belong to

classes CP90/250, LMB5/40 and LMB10/60 /Kayser 2005/.

In addition to the provisions of EN 13383, the design value obtained in the hydraulic design of revetments

with riprap armour layers in accordance with /GBB/ is the value below which 50 % (by weight) of the

stone fraction lie (G50 for weight classes and D50 for size classes). G50 is shown for a stone fraction of

class LMB5/40 (indicated in red) in Figure 4.1-1. G50 is also given for an average stone fraction (indicated

in green) which is defined by the line drawn between the nominal upper and lower boundaries.

Apart from the required G50 (D50)-value, the cumulative curve according to EN 13383 must lie within cer-

tain boundaries. An example for class LMB5/40 is shown by the hatched area in Figure 4.1-1.

Figure 4.1-1: Definition of the design values G50, shown here for class LMB5/40

The armourstones used must at least satisfy the 50 %-value of the mean cumulative curve (log-linear line

connecting the nominal class boundaries, see the green line given as an example in Figure 4.1-1). This

value must be checked during construction if such a check is specified in the contract. Guidance on how

to determine D50 and G50 is given in Annex 4.1-1.

10


The values of D50 and G50 for the most frequently used size classes are given in Table 4.1-1. The

boundaries mean cumulative curves and usual ranges of fluctuation of the size classes are shown in An-

nex 4.1-2. The procedure for selecting the size class described in section 5.2.1 is based on those values.

Table 4.1-1: 50 %-values for the standard size classes for riprap armour layers

Size class 50 % - value

CP90/250 D50 = 150 mm

LMB5/40 G50 = 14 kg

LMB10/60 G50 = 25 kg

The standard methods of constructing armour layers are specified for four different stone densities, s, i.e.

for 2300 kg/m3, 2650 kg/m3, 3000 kg/m3 and 3600 kg/m3.

4.2 Grout

Impermeable cementitious grouting materials are recommended. Compared with partial grouting with

impermeable grouting materials, the use of water-permeable grouting materials is very limited. Bitumi-

nous grouting materials (asphalt) are not dealt with in the description of the standard construction meth-

ods as they are no longer used on inland waterways in Germany for economic reasons and as they are

difficult to install under water. Guidance on the recommended quantities of grouting material is given in

/MAV/ which also lays down the requirements for the raw materials, the required tests and installation.

4.3 Filter layers

The standard requirements for geotextile filters are specified in /TLG/ and /ZTV-W LB 210/ and the re-

quirements for aggregate (granular) filters are set out in /ZTV-W 210/. Granular filters are generally un-

bound. The use of bound granular filters should be limited to the protection of relatively small areas which

can be easily inspected. Guidance on filter design is given in /MAG/ and /MAK/.

4.4 Separation layers

Depending on the application, aggregates as specified in /MAK/ or geotextiles as specified in /MAG/ and

/TLG/ may be used as separation layers. Separation layers between flexible linings and armour layers do

not act as hydraulic filters. If a separation layer is installed beneath an impervious lining, its water perme-

ability must be lower than that of the adjacent soil.

4.5 Impervious lining systems

4.5.1 General

The impervious linings used in the standard construction methods are all surface linings. Detailed guid-

ance on the various impervious lining systems, their characteristics and the limits of their application is

11


given in /EAO/. Vertical linings and the impervious cores of embankments are not covered by the stan-

dard methods of construction as they do not form part of the revetment.

4.5.2 Flexible lining systems

The following types of flexible lining are used on waterways:

natural clay liners

permanently plastic linings with clay and hydraulic binders

geosynthetic clay liners (GCL).

The material requirements and tests on flexible linings shall be as specified in /RPW/ and /EAO/.

The specifications of /TLG/ and the recommendations given in /MAG/ that are relevant to impermeable

linings also apply to GCLs.

4.5.3 Inflexible lining systems

The only inflexible lining systems included in the standard methods of construction are those comprising

armourstones fully grouted with an impermeable cementitious grouting material as specified in /MAV/ and

/EAO/. Guidance on the recommended quantities of grouting material is given in /MAV/ which also in-

cludes the requirements for the constituent materials, the required tests and installation.

5 Standard Methods of Construction

5.1 General

Revetments constructed by means of the standard methods may be permeable or impermeable, depend-

ing on the design. A separate lining may be placed beneath a permeable armour or separation layer, or

the armourstone armour layer may be fully grouted with an impermeable material. Any decision on the

need for a sealing system in a revetment must take hydrogeological and safety aspects into account (see

section 5.6.2).

Embedding the revetment to a depth of 1.5 m below the bottom of the waterway is a tried-and-tested

method of toe protection. Under certain boundary conditions the embedment depth may be reduced or a

toe blanket installed (see section 5.3).

A bottom revetment is generally only required if certain components or structures need to be protected,

e.g. impervious lining systems, inverted siphons just beneath the bottom of the waterway or sheet piling

at moorings. It must be checked whether there is a need for bottom revetments in manoeuvring areas.

The local stability (in accordance with sections 7.2, 7.3, 9.2 and 9.3 of /GBB/) of the standard methods of

construction described below will be ensured if the actions due to ship-induced waves and to currents are

taken into account in accordance with the design principles (see section 3) and the effects of anchor cast

are also considered. The global stability of water-side slopes protected by standard revetments shall be

verified, taking into account the relevant imposed loads detailed in section 7.4 of /GBB/.

12


The weight of the granular filter is fully taken into account in the mass per unit area in the geotechnical

design calculations. Significant structurally unfavourable excess pore water pressures do not occur in

granular filters. Stability is governed by the overall thickness of the armour layer and granular filter. This

has been taken into consideration in the standard methods of construction described below.

The weight of armourstone armour layers is governed to a considerable extent by the void ratio of the

layers which mainly depends on the method of installation. Values based on experience are given in Ta-

ble 5.1-1.

Table 5.1-1: Void ratio of armourstone armour layers as a function of the method of installation (based on depth measurements taken at the highest points of the armourstones)

In-situ density Void ratio, n Method of installation

loose 50 - 55 % The armourstones are dumped under water.

medium 45 % The armourstones are either dumped in dry conditions or

placed directly on the subgrade by an excavator.

dense 30 - 40 % The armourstone layer is finished manually or compacted

by the placement equipment.

The above empirical values apply to armour layers with the thicknesses specified in section 5.2 obtained

by depth measurements taken at the highest points of the armourstones (e.g. depth measurements per-

formed with a frame or a conventional staff with a plate foot with a diameter of around 30 cm or higher).

Measurements performed with spherical foot staffs are also common. In this case, the depth is measured

in the gaps between the top layer of stones instead of at the highest point of the stones. The layer thick-

nesses and void ratios obtained by depth measurements performed with a spherical foot staff are lower

than those obtained with a conventional staff (cf. section 8.2). If spherical foot diameters of 9 cm for

CP90/250, 12 cm for LMB5/40 and 15 cm for LMB10/60 are used, the upper edge of the revetment will be

around 3 cm to 5 cm lower than that measured at the highest points of the armourstones,

The standard methods of construction described below are based on a void ratio of 50 % as shown in

Table 5.1-1.

The requirements set out in /MSD/ for vegetation cover on the embankments of canals built above the

level of the surrounding countryside must be taken into consideration.

Revetments that do not extend over the full height of the slope (partial revetments) are not covered by the

standard methods of construction as they are customized solutions for particular ground conditions, e.g.

where the lower slope consists of bedrock, rendering it unnecessary to protect the complete slope. If the

lower edge of the partial revetment is embedded in the rock the armour layer thickness of the correspond-

ing standard method of construction may be adopted to provide a conservative design.

13


5.2 Armour layers

5.2.1 Permeable armour layers comprising riprap

This standard construction method comprises an armour layer of riprap as defined in section 4.1 placed

on a granular or geotextile filter.

Figure 5.2.1-1: Diagram of the cross-section of a permeable armour layer of riprap

Permeable armour layers comprising riprap readily adapt to ground deformations (flexibility). They have

sufficient resistance to ship collisions provided such collisions occur largely parallel to the axis of the ca-

nal.

The stability of revetments constructed by this method depends largely on the size of individual stones

and the thickness of the installed armour layer. These factors are dependent on the density of the stones

and the void ratio of the armourstone layer. Limited movement or even local displacements of stones may

occur under the loads assumed in the design and are taken into account in the calculations for standard

designs in /GBB/ (stability coefficient, B’B, = 2.3, see eq. (6-3) /GBB/). A limited degree of maintenance

work may therefore be required. Any damage to the revetments should be repaired as soon as possible.

The standard methods of constructing riprap revetments described in this Code will not ensure sufficient

stability (see section 5.6.5) if high flow loads occur in the vicinity of a revetment (e.g. in manoeuvring ar-

eas, waiting areas and at mooring points). The same applies to temporary moorings constructed for the

duration of the execution of the works.

The size of individual stones required for this particular standard construction method ensures that sur-

face erosion due to breaking waves, return currents, slope supply flow and propeller wash, if relevant, is

limited. It does not depend on the in-situ soil but solely on the hydraulic loads referred to. The required

mean sizes, D50, or mean weights, G50, of the individual stones and the resulting recommended stone

sizes determined in accordance with section 4.1 are given in Table 5.2.1-1 as a function of the density of

the stones. Ripraps with the required D50- or G50-values ensure that individual stones possess an ade-

quate degree of stability for the loading scenarios described in section 3.

Beyond Table 5.2.1-1 it may in certain circumstances be useful to select the next lowest size class. How-

ever, the lower size class must also comply with the value of D50 or G50 required for the relevant density

and the value should be within the range of variations typical of the relevant class as shown in Annex 4.1-

2. This represents a higher requirement for the next lowest size class and may therefore limit its applica-

tion.

14


The minimum thicknesses of the riprap armour layer required to ensure the stability of the revetment will

increase for a particular density of stone as the size class increases (see Annex 5.2.1-3). For this reason,

it may be appropriate to consider whether the next lowest size class with a G50- or D50 –value greater than

the mean value of that class should be used.

Table 5.2.1-1: Stone diameters, stone weights and size classes required for standard profiles approved for all types of inland waterway vessels (ES, GMS, SV, üGMS) for a range of densities (2300 – 3600 kg/m3)

Density

S

Required value

of D50

Required value

of G50

Recommended

size class

[kg/m3] [mm] [kg] -

2300 ≥ 260 ≥ 25 LMB10/60

2650 ≥ 200 ≥ 14 LMB5/40

3000 ≥ 160 ≥ 8 LMB5/40

3600 ≥ 120 ≥ 4 CP90/250

Relatively large stones and correspondingly thick layers are always required in the case of densities, s,

less than 2650 kg/m3. Generally speaking, the density, s, should be not less than 2650 kg/m3.

For intermediate density values, either the stone size for the next lowest density should be selected for

conservative designs or verification by calculation should be performed with the exact density as specified

in /GBB/.

As a rule, densities greater than 3000 kg/m3 can only be achieved with manufactured armourstones

(slags). If such armourstones are used, provisions on environmental impact must be taken into considera-

tion.

After the size class and density of the stones have been specified, the recommended thickness of the

armour layer must be selected from Table 5.2.1-2, taking the soil and type of filter into consideration.

However, the recommended thicknesses of armour layers on flexible linings only correspond to the speci-

fied minimum thicknesses if the groundwater level is lower than the canal water level when lowered by

shipping. If this is not the case, the safety against uplift must be verified (see Annex 5.6.2-1).

15


Table 5.2.1-2: Recommended armour layer thicknesses (riprap) for slope and bottom revetments, taking account of the soils specified in 3.4

Recommended armour layer thicknesses, dD [m]

for revetments with an embedded toe (embedment depth: 1.50 m)

Slope Bottom

Geotextile

as specified in MAG

Granular filter

as specified in

MAK

Geotextile

as specified in

MAG

Granular filter

as specified in

MAK

Density

[kg/m3]

Armourstone

size class

B1, B2, B5* B3 B4 All soils All soils All soils

2300 LMB10/60 0.70 0.85 0.95 0.70 0.70 0.70

2650 LMB5/40 0.60 0.70 0.80 0.60 0.60 0.60

3000 LMB5/40 0.55 0.60 0.70 0.55 0.60 0.55

3600 CP90/250 0.50 0.50 0.60 0.50 0.60 0.50

*B5 including flexible linings

In addition to the armour layer thicknesses specified in Table 5.2.1-2, the thicknesses of the armour lay-

ers required for slope and bottom revetments if alternative size classes of armourstones are used are

shown in Annex 5.2.1-1. The values take into account the armour layer thicknesses obtained by geotech-

nical calculations for slopes (shown in Annex 5.2.1-2) and the minimum thicknesses for slope and bottom

revetments that are required not only to resist ship collision and anchor cast, for example, but also to

ensure the stability of the armourstone layer (Annex 5.2.1-3). In each case, the higher value applies and

is rounded to the nearest 5/100 [m] in Annex 5.2.1-1 and in Table 5.2.1-2. No distinction has been made

between trapezoidal and rectangular-trapezoidal profiles. The recommended armour layer thicknesses

are based on mean values obtained from the results calculated for each type of profile.

The specific requirements stated in section 5.4 must also be taken into account in the case of armour

layers placed on flexible linings.

If stones with densities between the values stated in Annex 5.2.1-1 are used, the required thickness of

the armourstone layer can be interpolated, taking account of the minimum thicknesses shown in the dia-

grams in Annex 5.2.1-2.

5.2.2 Permeable armour layers comprising partially grouted armourstones

This standard method of construction comprises a armour layer of dumped armourstones as described in

section 4.1, partially grouted with an impermeable grouting material as described in section 4.2. The ar-

mour layer may be installed on a granular or geotextile filter.

16


Figure 5.2.2-1: Diagram of the cross-section of a permeable armour layer comprising partially grouted armourstones

Permeable armour layers comprising partially grouted armourstones have only a limited degree of flexibil-

ity which is governed by the quantity of grouting material used. Collisions by ships may result in damage

to the revetment. Any local damage to partially grouted armour layers should be repaired as soon as pos-

sible as it may otherwise become enlarged.

The execution of grouting work under water must be closely monitored /ZTV-W 210/.

The size class CP90/250 is recommended for the construction of partially grouted armour layers. The pro-

portion of fines in the size class must be limited by specifying 90 mm as the minimum value of D5 in the

contract documents in order to ensure a sufficiently large void size. Stones of class LMB5/40 may also be

used.

The thicknesses recommended for partially grouted armour layers comprising armourstones of classes

CP90/250 and LMB5/40 placed on soil types B1 to B5 or a flexible lining are stated in Annex 5.2.2-1. The

values apply to both bottom and slope revetments and take the density of the stones into account. The

armour layer thicknesses obtained in calculations performed for the geotechnical design of the slope

(shown in Annex 5.2.2-2) and the minimum thickness, which is usually 40 cm for the size classes used,

have been taken into consideration. The higher value, which has been rounded to the nearest 5/100 [m]

in Annex 5.2.2-1, shall apply in each case. No distinction has been made between trapezoidal and rec-

tangular-trapezoidal profiles. The recommended armour layer thicknesses are based on the mean values

of the results calculated for both types of profile.

The specific requirements stated in section 5.4 must also be taken into account in the case of armour

layers placed on flexible linings.

If stones with densities between the values stated in Annex 5.2.2-1 are used, the required thickness of

the armourstone layer can be interpolated, taking account of the minimum thicknesses shown in the dia-

grams in Annex 5.2.2-2.

5.2.3 Impermeable armour layers comprising fully grouted armourstones

This standard method of construction comprises a armour layer of dumped armourstones as described in

section 4.1, fully grouted with an impermeable cementitious grouting material as described in section 4.2.

This type of armour layer may only be installed on a geotextile separation layer as described in section

4.4. The weight class LMB5/40 or LMB10/60 is recommended.

17


Figure 5.2.3-1: Diagram of the cross-section of an impermeable armour layer comprising fully grouted armourstones

Any underlayers required beneath an impermeable armour layer must be less permeable than the in-situ

ground, but must nonetheless be filter-stable. Otherwise there is risk that due to a local damage to the

impermeable revetment the hydraulic head of the canal would become distributed over a large area below

the revetment, leading to damage due to buoyancy.

Impermeable armour layers comprising fully grouted armourstones have no flexibility. Damage may occur

as a result of ship collision. Any damage to impermeable armour layers must be repaired in order to re-

store their sealing function.

The minimum thicknesses of impermeable, fully grouted armour layers shown in Annex 5.2.3 are suffi-

cient if the groundwater level is always lower than the canal water level when lowered by shipping. If ex-

cess water pressure acts behind the impervious lining, either temporarily or permanently, the thicknesses

of the armour layer required to ensure sufficient safety against uplift must be calculated. The required

minimum thicknesses and examples of the required armour layer thicknesses obtained by calculation are

given in Annex 5.2.3 for various excess water pressures.

5.3 Toe protection

The stability of slope revetments depends, amongst other things, to a great extent on the design of the

toe. On the basis of past experience, an embedded toe is recommended for the standard methods of

construction. For soil types B2, B3 and B4 defined in section 3.4, the standard methods of construction

described in this Code must include an embedded toe with a minimum embedment depth, t, of 1.50 m

below the design level of the bottom of the waterway (see Figure 5.3 1). This also applies to cohesive

soils (soil type B5) with poor resistance to erosion. The toe trench is generally filled with in-situ soil.

18


Figure 5.3-1: Design of the toe protection

Whenever the in-situ soil beneath the revetment is of soil type B1 the embedment depth of the toe may

be reduced to 1 m if the armour layer thicknesses specified in Annexes 5.2.1-3 and 5.2.2-2 are main-

tained or, alternatively, a toe blanket as shown in Figure 5.3 1 is installed. These measures are also pos-

sible in the case of bedrock or firm cohesive soils (B5) that are resistant to erosion.

The standard methods of construction do not consider scour directly at the toe of the slope as experience

has shown that scour caused by shipping only occurs at a distance of several metres from the toe. Never-

theless, if any local scour should occur directly at the toe of the slope it must be remedied during mainte-

nance work. Alternatively, the depth of the toe protection beneath the bottom of the waterway may be

extended by increasing the standard depth of 1.5 m by the forecast depth of the scour or the toe trench

may be filled with material that is coarser than the in-situ soil, such as gravel. The material must prevent

loss of the in-situ soil. Revetments may also be designed individually in accordance with /GBB/ to take

scour into account.

Excavation of a toe trench in highly erosive soils such as soil type B4 may be difficult. In such cases, very

low slope inclinations should be selected for the toe trench and the revetment should be installed imme-

diately after the trench has been excavated.

Sheet pile walls are only installed at the toe in exceptional cases and are therefore not considered in the

standard methods of construction. The actions and resistances on the sheet pile wall must be determined

as specified in /GBB/. The armour layer thicknesses specified for the standard construction methods in

this Code of Practice may be used to achieve a conservative design. Sheet pile walls are stable in the

long term but are a relatively costly method of toe protection. They can only be constructed in driveable

19


soils without obstacles to driving such as the remains of previous revetments. The connection between

the slope protection and the head of the sheet pile wall must be filter-stable. Scour to depths of 1.50 m

(for soil types B2 to B4, depending on the resistance to erosion, but also for soil type B5) or of 0.75 m (for

soil type B1) in front of the sheet pile wall must be taken into account in designs in accordance with sec-

tion 7.2.5.5 of /GBB/.

5.4 Flexible linings

Permeable revetments comprising riprap or partially grouted armourstones (see sections 5.2.1 and 5.2.2

respectively) may be installed on a flexible lining as described in section 4.5.2. The use of underlayers

that are more permeable than the in-situ soil is not permitted as the development of any seepage paths in

the plane beneath the flexible lining must be avoided. There is otherwise a risk that the pressure potential

of the water in the canal could become distributed over a large area below the lining if local damage to

the lining occurs, leading to damage due to buoyancy.

If clay liners are used, only geotextile separation layers as described in section 4.4 should be installed

between the lining and the armourstones. If granular filters are used there is a risk that any defects in the

lining occurring after installation of the clay may become filled with filter material, resulting in permanent

seepage points. By contrast, minor defects in the clay liner can “heal“ due to the superimposed load of

the armour layer.

Owing to the lack of experience with geosynthetic clay liners (GCLs) and permanently flexible linings with

clay and hydraulic binders, their use is currently only recommended for low-risk canal sections higher

than the surrounding ground surface which do not require frequent monitoring /EAO/. Up-to-date informa-

tion on the use of such liners can be found in articles published by the BAW (BAW-Brief publications) or

on the BAW website (www.baw.de).

Geosynthetic clay liners are generally installed with a sand mat (a geotextile filled with sand or a mineral

material to weigh it down). The armourstones placed on GCLs may not exceed class LMB5/40, without

oversized pieces of stone, in order to minimize any local unevenness of the bentonite layer caused by the

impact of the armourstones during installation.

Permanently flexible linings with clay and hydraulic binders cannot be installed on inclined surfaces owing

to the flowing properties of the materials.

5.5 Freeboard height

Slope revetments should extend to a height of at least 70 cm above the relevant design water level to

take account of possible wave run-up. The design water level will either be the upper operating water

level, BWo, or the highest navigable water level, HSW.

5.6 Selection of a standard method of construction

5.6.1 General

The choice of a standard method of construction is influenced by the local boundary conditions (e.g.

ground, topography, groundwater table) and the requirements (e.g. for loads due to shipping, actions due

20


to leisure activities, environmental impact) that the revetment needs to satisfy. The correct balance be-

tween the various, possibly opposing, factors must be achieved. The following points must be considered

or specified when selecting a standard method of construction.

5.6.2 Requirement for an impervious lining

An impervious lining may need to be installed on a waterway if the lowest operating water level of a canal

is higher than the highest level of the groundwater table, i.e. there is a permanent hydraulic gradient be-

tween the canal and the groundwater (see top diagram in Figure 5.6 1). The following aspects must be

considered:

a) safety of the embankment (achieving an adequate level of safety in load case 1),

b) waterlogging of adjacent land or flooding of buildings,

c) high seepage losses (standard value of permissible seepage losses based on the cost of replacing

lost water: 15 l/s/km),

d) adverse effects on drinking water reservoirs.

Sufficient groundwater data is needed to determine whether an impervious lining is required. The data is

also needed for the preservation of evidence.

Possible methods of constructing the transitional zone between an impervious lining and the permeable

sections of a revetment are shown in Figure 5.6-1 (centre) and must be considered if an impervious lining

is to be installed. It must be taken into account that impervious linings may be exposed to land-side ex-

cess water pressure if installed in the transitional zone between a cutting and a canal section built above

the level of the surrounding ground surface or if the groundwater and canal water levels are subject to

large fluctuations. The thickness (or weight) of the armour layer will then need to be calculated as speci-

fied in section 7.3 of /GBB/ and the resulting layer thicknesses may be high. Examples of the thicknesses

of armour layers placed on clay liners and GCLs that are required to take account of a range of excess

water pressures are shown in Annexes 5.6.2-1 and 5.6.2-2 (for riprap and partially grouted armour layers

respectively). Irrespective of this, the minimum thicknesses specified in Annex 5.2.1-3 or Annex 5.2.2-3

must be taken into account.

Alternatively, the groundwater level can also be limited to a structurally acceptable maximum level by

technical measures (e.g. drainage, wells) (cf. Case a) in Figure 5.6 1, centre). The possible environmental

impact of such measures must be considered.

21


Selection criterion Type of revetment

BWu > max. GW

BWumax. GW

Impermeable revetment, if appropriate

a.) Impermeable revetment, if appropriate

If the groundwater level is limited to the maximum permitted

value obtained in the verification of safety against uplift (sec-

tion 7.3.3 of /GBB/) at the lower operating water level, BWu,

with the actual or planned weight of the armour layer.

BWu ≤ max. GW

and

BWo ≥ min. GW

max. GW

min. GW

BWu

b.) Permeable revetment

Water losses occur and must be acceptable. It must be

checked whether the adjacent areas could become water-

logged.

BWo < min. GW

min. GWBWo

Permeable revetment

BWu: lower operating water level

BWo: upper operating water level

max. GW: highest anticipated groundwater level

min. GW: lowest anticipated groundwater level

Figure 5.6-1: Criteria for the selection of an impermeable or permeable revetment

Impervious linings must extend at least 0.50 m above the upper operating water level (BWo) or the high-

est navigable water level (HSW).

5.6.3 Soil classification

The required thickness of the armour layer depends to a large extent on the type of ground on which the

design of the revetment is based. If different types of soil are present or the soil is stratified, it will be nec-

essary to decide which type of soil the design should be based on. The type of soil (classified as type B1

to B5 in accordance with section 3.4) that is selected must always be the one that results in the greatest

armour layer thickness. Thin soil strata (= 1 m) may generally be disregarded.

5.6.4 Requirement for a filter or a separation layer

Reference should be made to either /MAG/ (for geotextiles) or /MAK/ (for granular filters) to determine

whether a filter is required for the planned slope or bottom revetment.

22


Geotextile separation layers should be installed beneath impermeable armour layers and on top of imper-

vious clay liners. In addition, separation layers are required to prevent any mixing or penetration of layers

of different types of mineral particles (e.g. non-cohesive soil placed on soft or pulpy ground).

5.6.5 Selection of an armour layer

If properly executed, the armour layer construction methods described in section 5.2 may be regarded as

technically equivalent on reaches and are all applicable in principle. However, each construction method

has particular strengths and weaknesses which must be evaluated when a construction method is se-

lected for a specific project. The requirements for construction and operation (execution, resistance, per-

meability, etc.), for maintenance (ease of inspection, magnitude of damage, cost of repairs),

environmental impact and cost-effectiveness (production and maintenance costs) must be considered.

The loads due to the propulsion and steering units of vessels will be relatively high in manoeuvring ar-

eas (e.g. mooring points and turning basins, lock waiting areas or areas in which the cross-section radi-

cally changes). Such loads result in greater hydraulic actions than on reaches and affect the stability of

individual stones. Designs taking these aspects into account would result in armour layer dimensions far

exceeding those obtained for the standard methods of construction.

Armour layers comprising partially or fully grouted armourstones (sections 5.2.2 and 5.2.3) are recom-

mended whenever slope or bottom revetments are required to provide protection against scour in ma-

noeuvring areas. Other measures are also possible, such as greater water depths at mooring points or

dolphins to ensure a minimum distance between vessels and the banks in order to limit the loads due to

bow thrusters.

Acceleration and stopping zones in lock waiting areas must be inspected to determine if there is a risk of

scour. In the case of modern vessels, the length of the acceleration area can generally be taken to be

around 100 m for self-propelled barges and 200 m for push-tow units. The length of the stopping area

required for self-propelled barges and push-tow units may be taken to be around 200 m and 300 m re-

spectively.

6 Other Methods of Construction

6.1 General

Two other frequently-used methods of construction are described in the following sections. They are:

revetments in combined rectangular-trapezoidal profiles (KRT-profiles) (see section 6.2) and

impermeable, erosion-resistant pavements (see section 6.3).

Although combined rectangular-trapezoidal profiles are regarded as standard cross-sections /RiReS/ the

revetments in such profiles are exposed to lower loads than those in rectangular-trapezoidal or trapezoi-

dal profiles and are therefore not included in the standard methods of construction.

Impermeable pavements used to be installed extensively on waterways. However, they have become

less widespread over the past two decades owing to technological and economic developments and are

therefore no longer regarded as a standard method of construction.

23


Stone-filled wire mesh elements (such as gabions and rock mattresses) have not been included in the

standard methods of construction as they are only used to a small extent, mostly in areas with unusual

geometrical boundary conditions (e.g. as regards the slope inclinations).

6.2 Revetments in combined rectangular-trapezoidal (KRT) profiles

Revetments in combined rectangular-trapezoidal profiles serve to protect the short slopes above sheet

pile walls (see /RiReS/ for standard dimensions) which are exposed to considerably lower hydraulic loads

than the slopes in trapezoidal profiles.

The following methods of construction are possible:

60 cm riprap, minimum class LMB5/40, on a granular or geotextile filter (see section 5.2.1) or

40 cm partially grouted armourstones of class CP90/250 (quantity of grouting material as specified in

/MAV/) on a granular or geotextile filter (see section 5.2.2).

6.3 Impermeable erosion-resistant pavements

Pavements are revetments with a homogeneous structure, uniform thickness and a uniform mass per unit

area (e.g. asphalt concrete). Owing to their internal strength, they do not require a protective covering.

Pavements may also be armour layers comprising elements of the same type joined together to form a

continuous area (e.g. interlocking concrete blocks).

Impermeable erosion-resistant pavements must protect and seal the slopes and the bottom of waterways.

They are made of either asphalt or concrete.

Concrete is a rigid material and cannot adapt to deformations of the subgrade. Asphalt possesses a de-

gree of flexibility due to the viscoelastic properties of the bitumen and is able to resist external stresses

such as settlements or compressive or shearing stresses to a certain extent, depending on the tempera-

ture.

Concrete and asphalt pavements are easily damaged by sudden, high levels of local stress such as ship

collisions.

A separation layer must be placed between an impermeable pavement and the in-situ soil or an under-

layer, if used. The occurrence of seepage paths in the plane beneath the impermeable pavement must be

avoided. Separation layers or underlayers that are more permeable than the subgrade are therefore not

permitted beneath impermeable pavements as the pressure potential of the water in the canal would be

distributed over a large area beneath the impermeable pavement if the latter suffered local damage. The

transient stresses due to the changes in pressure caused by water-level drawdown would then result in

extensive damage to the impermeable pavement to a depth of around 1 m below the water level due to

buoyancy.

The minimum concrete thicknesses are 15 cm for installation in dry conditions and 20 cm if the concrete

is placed under water.

24


The recommendations given in /EAAW/ apply to the planning and installation of asphalt pavements for

waterways. Generally speaking, they may only be installed in dry conditions.

Impermeable bituminous pavements are susceptible to root penetration. Maintenance work, especially on

asphalt revetments, must include the removal of any vegetation.

The safety against uplift must be verified in accordance with section 7.3 of /GBB/ if the groundwater level

is high.

7 Vegetation Cover in Standard Methods of Construction

7.1 General

Suitable vegetation should be planted or grown from seed on the banks above the water level in all stan-

dard methods of construction for the following reasons:

to encourage colonization of the banks of waterways by flora and fauna

to improve natural environments and landscapes

to increase the stability of the banks by means of root growth

to provide greater protection of shipping against wind

However, possible adverse effects must also be considered, for example:

increased maintenance costs owing to care of the vegetation cover

collapse of banks at the edge of the vegetation cover

damage to the impervious lining due to root penetration

increase in the amount of plant debris (plant material or dead plants) in the navigation channel

decreased visibility for boatmasters due to high vegetation

reduction in the stability of embankments (see /MSD/).

Generally speaking, the standard methods of construction provide only limited opportunities for vegetation

growth. This is due to the specified bank geometries and revetment designs as well as the fact that re-

vetments in the standard cross-sections are exposed to relatively high loads due to shipping.

Vegetation may develop naturally as a result of seed dispersal by the wind or by plant material being

washed up and deposited in the silt that accumulates in the cavities between the armourstones. The es-

tablishment of vegetation cover may be encouraged and accelerated by covering the armourstone layer

with unfertilized topsoil and by sowing grasses and herbs native to the locality or by other means. The

topsoil should not only be placed on top of the armourstone layer but should also fill as many of the cavi-

ties between the armourstones as possible. However, topsoil is likely to be rapidly washed away in the

zone of fluctuating water levels due to the hydraulic actions on the bank. It should therefore only be

placed on slopes above a height of at least 50 cm above the normal or mean water level.

25


The stability and rate of vegetation growth can be increased if the cavities in armourstone layers are

completely filled with alginate-enriched topsoil. The topsoil mixture is produced in specialized mixing

plants and consists of finely sieved topsoil to which alginate with montmorillonite colloids (i.e. bentonite)

has been added. Mixing the alginate-enriched topsoil with water produces a flowable clay-humus complex

with thixotropic properties that can be pumped into the cavities between the stones (see p. 16 of /STLK

207/). When installed, the alginate-enriched topsoil has a higher resistance to erosion than normal topsoil

and can therefore be placed in the armour layer directly above the normal or mean water level.

Furthermore, planting woody plants or cuttings (e.g. of shrubby species of willows) or plant plugs (reeds

or other herbaceous perennials of around 15 cm in length and diameter, with the root ball frequently

wrapped in coir matting) in the unfertilized topsoil or alginate-enriched topsoil placed in the cavities be-

tween the dumped stones is recommended where technically feasible and provided that the stability of

the revetment is not jeopardized. Plant plugs should be planted in rows parallel to the bank (with the dis-

tance between the rows being approx. 30 – 40 cm). The spaces between the plants should also be

approx. 30 – 40 cm.

The different moisture requirements of the various types of vegetation must be taken into consideration.

Plants such as the common reed or yellow iris thrive in wet conditions such as those found at normal or

average water levels and up to around 10 cm to 20 cm above them. Sedges and marshland perennials

can grow in slightly drier conditions, but do not thrive particularly well in locations higher than 30 cm to

40 cm above the normal or average water level.

The correct light conditions are also important for successful vegetation growth. Reeds only thrive if there

is not too much shade on the banks. Woody plants may adversely affect the growth of grasses, herbs or

reeds sown or planted nearby, depending on the light conditions.

Successful vegetation growth depends to a large extent on local conditions so that it is not possible to

give any general recommendations on which types of plant to select. It is recommended that vegetation

plans indicating suitable types of plants be drawn up by experts.

Generally speaking, plants that are native to the locality and suitable for the site should always be used.

Seeds and plant cuttings for a particular revetment should be sourced from the locality in which they are

to be used.

Vegetation cover should always extend over continuous areas. Solitary plants may result in local in-

creases in flow loads which would adversely affect the stability of the individual plants.

7.2 Permeable armour layers comprising riprap or partially grouted armourstones as de-

scribed in sections 5.2.1 and 5.2.2 respectively

The growth of vegetation on permeable armour layers comprising riprap or partially grouted armourstones

depends on a variety of factors and boundary conditions. In addition to the points discussed in section

7.1, other important factors include the thickness of the armour layer, the stone sizes, the size of the cavi-

ties in the stone layer, the stability of the armour layer, including its resistance to the displacement of

stones, and the different wave loads occurring on the various types of waterway.

26


Vegetation cover may be established by sowing grasses and herbs native to the locality or planting reeds,

herbaceous perennials or woody plants, for example, in topsoil or alginate-enriched topsoil placed on the

armour layer (see section 7.1).

Wave action may cause local displacement of the stones in riprap armour layers, resulting in damage to

plants. Stone displacement rarely occurs in partially grouted armour layers. On the other hand, the sur-

face on which plants can take root is smaller than in the case of riprap armour layer. Compliance with the

recommended quantity and distribution of the grouting material specified in /MAV/ is required in order to

optimize the conditions for vegetation cover on partially grouted armour layers.

The opportunities for the establishment of fauna provided by the empty cavities between the stones in the

zone of fluctuating water levels and under water depend on the void ratios of the armour layer and stone

surface available for colonization, with higher void ratios and a larger available stone surface being more

favourable. Compliance with the recommended quantities and distribution of grouting material specified in

/MAV/ is therefore an important factor if fauna is to colonize the banks.

7.3 Impermeable armour layers comprising fully grouted armourstones as described in section

5.2.3

Root penetration is generally ruled out on fully-grouted impermeable armourstone revetments owing to

the absence of voids in the armour layers. As a result, grass and herbaceous plants are unable to grow

on such revetments.

It is not permitted to plant woody perennials or reeds on the slopes, and any vegetation of this kind must

always be removed immediately.

7.4 Guidance on vegetation cover on flexible linings

Grasses and herbs may be sown on revetments with flexible linings. Other types of vegetation must be

planted at a sufficient distance from the lining (see /MSD/). This is due to the fact that there are several

varieties of woody plants and reeds whose roots are able to penetrate flexible linings. Undesirable plant

growth on a lining can lead to high maintenance costs. The types of undesirable vegetation that could

grow on the lining must be assessed in advance and maintenance planned accordingly.

8 Guidance on Invitations to Tender, Execution of the Works, Quality Control

and Maintenance

8.1 General

Invitations for tenders for slope and bottom protection systems must be based on /STLK 210/, taking ac-

count of the following codes of practice in particular:

Code of practice “Use of standard construction methods for bank and bottom protection on inland

waterways“/MAR/

Code of practice “Use of geotextile filters on waterways“ /MAG/

Code of practice “Use of granular filters on waterways“ /MAK/

27


Code of practice “Use of cement-bonded and bituminous materials for grouting armourstones on

waterways“ /MAV/

Recommendations for the use of lining systems on the beds and banks of waterways/EAO/

The following sections 8.2 and 8.3 give additional guidance on issuing invitations to tender and on the

execution of the works.

In addition, it must be explicitly stated which parts of the above codes of practice would have to be com-

plied with under the contract for execution of the works.

8.2 Invitations to tender

8.2.1 General

The points stated in section 8.2 must be included in the contract documents at the appropriate places.

In additional to the general specifications, compliance with the technical contract conditions set out in

/ZTV-W LB 210/ must be stipulated in the contract for execution of the works.

The properties of the materials must be specified by the Client. The requirements must be specified in the

invitation to tender in accordance with the guidance given in /ZTV W LB 210; MAK; MAV; MAG/.

The methods used to install the required materials must ensure that the correct quantity per unit area is

placed. It is recommended that documentation relating to the installation methods and equipment, espe-

cially in the case of installation under water, be requested when a bid is submitted.

All services relating to quality control and the inspection of the construction work (cf. 8.4) must be in-

cluded in the standard price unless stated separately in the bill of quantities.

Any connections to structures that need to be executed must be described in detail and, if necessary, the

required drawings must be supplied.

The permitted ranges of tolerances for the subgrade must be stated.

It must be specified in the invitation to tender whether bidders are required to provide documentation on

the type tests for construction products and methods and

the manufacturers’ declarations of conformity and factory production control (FPC) certificates for

construction products

on submission of their tender.

Such documentation must always be requested for the materials and methods listed in Table 8.2.1-1.

28


Table 8.2.1-1: Documentation to be provided on submission of a tender

Declaration of conformity

and factory production

control (FPC) certificate

Type

testing

Geotextiles and geotextile-related products

(EN 13253) X X

Armourstones (EN 13383) X

Geosynthetic barriers (EN 13362) X X

Permanently flexible lining materials with

clay and hydraulic binders X

Mat

eria

ls

Cementitious and bituminous grouting

materials X

Grouting methods X

Met

ho

ds

Methods of installing sealing materials and

impervious lining systems X

The requirements for construction products and methods must be specified clearly and in detail as any

bids not including the required documentation stated in Table 8.2.1-1 will automatically be excluded from

the tendering procedure.

8.2.2 Armour layer

The following points must be taken into account, as appropriate:

specification of the required mean stone weight, G50, stated in Table 5.2.1-1 or the required mean

stone size, D50, for riprap armour layers with the appropriate density

the requirements for contract documents stated in /MAV/ for partially or fully grouted armour layers

In addition to factory production control and the quality checks performed by the Client (see section 8.4) it

is recommended that the Contractor be required to submit additional proof of compliance with the re-

quirements for armourstones set out in /DIN EN 13383/ and /TLW/. This requirement should be included

as an additional item in the invitation to tender. The tests must be performed on the armourstones as

delivered to the construction site by a testing institute accredited in accordance with /RAP Waba/. It is

recommended that one test be performed for every 10,000 m2 of the revetment.

The Contractor‘s first quality control test must be performed on the first delivery of armourstones.

The procedure for determining the mean thickness of the installed armour layer must be specified (meas-

urement programme, measuring method and method of evaluating the measurement programme). The

29


measurement profiles must be specified by the Client. The measurements shall be recorded in a test

report that must be submitted to the Client (see also 8.4.2).

Checking and levelling of the armourstone layer should be specified in the contract if connections to adja-

cent structures are required.

If topsoil is placed on the armour layer it must be checked that it contains no plant root material that could

damage the armour layer or subsequently hinder maintenance work. Problems may arise, for example, if

black locust or Japanese knotweed is introduced unintentionally. The plants concerned can even grow

from small pieces of root material. The origin of the topsoil to be installed and the types of vegetation at

the location from which the soil is taken must be checked.

8.2.3 Underlayers

Underlayers, if required, must be appropriate for the profile.

Any material installed beneath permeable revetments must be filter-stable (see /MAK/) and more perme-

able than the in-situ soil. Single underlayers may comprise either sand and gravel or stone chippings and

crushed rock.

The permeability of underlayers installed beneath impermeable revetments must not exceed that of the

in-situ soil.

8.2.4 Minimum requirements for secondary tenders

Secondary tenders are only permitted if they satisfy the minimum requirements set out in the contract

documents. The minimum requirements for slope and bottom protection systems and the conditions un-

der which they apply must be clearly described in the specification of works for the Contractor.

The thickness of the armour layer set out in the bill of quantities only applies in conjunction with the speci-

fied minimum density, the specified size class of the armourstones, the type of filter and the specified

method of measurement.

If changes to the revetment are proposed in secondary tenders (e.g. in the thickness of the armour layer,

size class, density, type of filter or impervious lining) it must be verified that the modified revetment would

satisfy the minimum requirements. The verifications must be based on the hydraulic actions assumed in

the revetment design described in the invitation to tender. The hydraulic actions of relevance to the stan-

dard methods of construction are specified in section 3.

If a secondary tender is submitted, the bidder must provide, as a minimum, verification of the following in

the bidding documents:

stability of the revetment in accordance with /GBB/ if the selected method of construction differs

from the standard methods of construction specified in /MAR/

erosion resistance of the armour layer, e.g. by verification of the required D50–value specified in

/GBB/ or /MAR/

proof of compliance with the minimum thicknesses specified in section 5.2 or Annex 5.2.1-3

density and size class of the armourstones, with a minimum value of D50 or G50

30


void ratio of the armourstone layer, planned type of filter and its characteristics (thickness on in-

stallation, density)

verification of the overall stability in accordance with DIN 4084 (if relevant)

Any changes in the relevant quantities and dimensions must be stated.

8.3 Execution of the works

In addition to the requirements stated in section 8.2, points that need to be considered during the execu-

tion of the works are set out below.

Accompanying commercial documents and the CE-marking as specified in /DIN EN 13383, DIN 13253

and DIN 13362/ must be submitted prior to execution of the works and the values stated in them must

comply with the invitation to tender.

The Client’s first quality check shall be performed on the first delivery of armourstones.

The surfaces of the subgrade (rough subgrade, lining, filter, etc.) must be free of any foreign material.

Erosion channels or holes in the rough subgrade must be eliminated by installing an underlayer, if appro-

priate.

The materials must be prepared and mixed in such a way that their characteristics and composition com-

ply with those verified in the suitability test and they do not contain any harmful impurities.

Compliance of the finished layer of stones with the requirements must be verified by suitable methods

(e.g. sounding in sufficiently closely spaced profiles). The profiles should, where possible, correspond to

those used for measuring the depth of the unprotected bottom of the waterway.

Mechanical loading of the finished revetment or its layers by construction machinery is only permitted if it

is verified on the construction site that such loads will not cause any damage.

Bubbles of mud may occur beneath geotextiles in the case of fine-grained soils and impervious linings

and the appropriate checks of the finished revetment must be conducted by divers. If mud bubbles are

detected, their relevance for the works must be assessed by consulting a geotechnical expert familiar with

such matters and, if necessary, measures to eliminate such bubbles and prevent any further occurrence

thereof must be undertaken.

Impervious linings and filter layers that are not resistant to erosion and anchor cast must be protected by

installing the armour layer immediately (or within 48 h at the latest /ZTV W LB 210/). If this deadline is not

observed during construction, the Contractor must state the length of time that elapsed before the armour

layer was installed and the means used to check the stability or strength of the lining material. Such de-

viations from the requirements are only permitted after prior approval by the Client.

31


8.4 Quality assurance

8.4.1 General

Compliance with the requirements for the production, characteristics and processing of construction ma-

terials, construction material systems and components as well as for the finished works is ensured by

quality assurance procedures comprising the quality control of the construction materials and the execu-

tion of the works.

The construction materials used for slope and bottom protection systems on waterways must be as speci-

fied

solely in harmonized European Standards (for armourstones, aggregates),

in harmonized European Standards in conjunction with additional specifications for waterways en-

gineering (geotextiles) and

in national rules for waterways engineering (grout, clay, permanently flexible lining materials with

clay and cement).

Products in accordance with harmonized European Standards (such as armourstones and aggregates)

must be supplied with the accompanying commercial documents, the CE-marking and the declaration of

conformity. The CE-marking may only be affixed to the construction products used for the applications

covered by this Code of Practice if the manufacturer has drawn up a declaration of conformity stating that

the product conforms to the relevant harmonized standard and if the factory production control (FPC)

certificate specified in the relevant standard has been issued.

Compliance of the properties of geotextiles with harmonized European Standards is confirmed by the CE-

marking. In addition, compliance with the supplementary requirements specific to waterways engineering

is certified by a type testing certificate issued by the Federal Waterways Engineering and Research Insti-

tute (BAW).

In the case of grout, clay and permanently flexible lining materials with clay and cement, verification of the

suitability in principle of the materials and installation methods is confirmed by a type testing certificate

issued by the Federal Waterways Engineering and Research Institute. The suitability of construction ma-

terials and installation methods for a particular site must be verified at the beginning of the execution of

the works by means of a suitability test performed by the Contractor.

A summary of the technical rules of relevance to the construction of navigable waterways and the associ-

ated fields of application is given in the List of Technical Rules for Waterways Engineering /TR-W/ drawn

up for the Federal Waterways and Shipping Administration (WSV) by the Federal Ministry for Transport,

Building and Urban Affairs.

The Contractor bears the responsibility for executing the works as specified in the contract. He must ver-

ify that the works have been correctly executed by conducting the quality control procedures for construc-

tion materials and procedures set out in /ZTV-W 210/. In addition to the FPC during the production of the

materials and the Contractor’s quality control procedures, the Client should perform quality checks on the

construction materials and during execution of the works. The type and scope of the quality checks must

be set out as far as possible in the specification of the works so that the Contractor is able to make the

32


necessary preparations to deal with any interruptions in the construction work and make available any

equipment that may be required.

Quality checks for works executed under water should be carried out by divers on the Client`s behalf and

samples should be taken if necessary.

8.4.2 Depth measurements for quality assurance

It is stipulated in /ZTV-W 210/ that the thickness of the finished revetment must be verified. This is usually

done by means of depth measurements performed with a staff. In addition, depth measurements taken

over swathes of the waterway bed are recommended to check the quality of the works.

The results of the depth measurements must be recorded and stored to enable them to be compared with

the regular measurements conducted as part of safety inspections and so that any damage can be re-

paired during maintenance work.

If acceptance measurements are conducted by means of a staff, attention must be paid to the design of

the tip. The thicknesses of the armour layers specified in section 5.2 apply to depth measurements based

on the level of the highest points of the armourstones, e.g. depth measurements performed with a frame

or a staff with a large disc-shaped foot with a diameter of around 30 cm or higher. Measurements per-

formed with spherical foot staffs are also common (with foot diameters of 9 cm for CP90/250, 12 cm for

LMB5/40 and 15 cm for LMB10/60, cf. guidance in /STLK 210/); in this case the depth is measured in the

gaps between the armourstones instead of at their highest points. The layer thicknesses and void ratios

obtained by depth measurements performed with a spherical foot staff are lower than those obtained with

a conventional staff (cf. section 5.1). If the spherical foot diameters stated above are used, the measured

upper edge of the revetment will be around 3 to 5 cm lower than that measured at the highest points of

the armourstones.

Precise methods of measurement must be used to perform depth measurements over swathes of a re-

vetment. Measurements of the level and depth of any point on the bottom of the waterway must be accu-

rate to within a maximum of +/-10 cm, taking account of all factors influenced by the survey vessel and its

movements.

The grid selected for the digital model of the bed of the waterway should be such that the highest possible

resolution of the structures on the bottom and on the slopes is achieved. The resolution depends on the

measuring method (depth measurements taken from a boom or by multibeam echo sounding), the ship

speed, signal frequency, footprint and number or spacing of the sensors (transducers). A grid with a

maximum size of 0.30 x 0.30 m2 is recommended.

8.5 As-built documents

As-built documents in which all of the most important information is recorded must be prepared for the

finished slope and bottom protection system. They include documentation of the following:

the location of the works

the type of ground in accordance with /DIN EN ISO 14688/ and /DIN 18196/ (soil investigation re-

port)

33


the method used to construct the slope or bottom protection system, with a detailed description of

the installation method, toe design and connections to adjacent structures

in the case of secondary tenders, verification of compliance with the minimum requirements

in the case of flexible linings comprising soils and permanently flexible lining materials with hy-

draulic binders, the mechanical soil parameters on installation, the type and quantity of any addi-

tives and the source of the materials

the installation plan for geosynthetic clay liners (type, product information)

the type of filter (geotextile: type, product information; granular filter: grading)

the armourstone size class and thickness of the installed armourstone layer, type of stone, source

of the stone (quarry or, for manufactured stones, the producer), particle size or mass distribution,

densities, CE–marking and conformity certificates

for fully or partially grouted armour layers, the type and quantity of grout used (l/m2), installation

method, installation plan with all relevant data (losses due to erosion, flow diameter of the grout,

quantities used)

daily site records, including any details of particular significance (e.g. any defects detected during

quality checks or reservations during acceptance, divers’ reports, records of depth measurements)

acceptance depth measurements of the slopes and the bottom

8.6 Guidance on maintenance

Riprap armour layer can be placed or restored to their original condition under water without the use of

specialized equipment.

Contracts for the installation and repair of grouted armour layers under water must be placed with special-

ist companies employing procedures which have passed the basic test specified in /MAV/ or working as

directed by the Federal Waterways and Shipping Administration (WSV).

34


9 Literature

/BinSchStrO/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Binnenschifffahrtsstraßen-Ordnung, BinSchStrO

Wasser- und Schifffahrtsverwaltung des Bundes, 2005

/DIN EN 13253/ Deutsches Institut für Normung e. V. (Hrsg.)

Geotextilien und geotextilverwandte Produkte

(EN 13253, Geotextiles and geotextile-related products)

Beuth-Verlag, Berlin


Geosynthetische Dichtungsbahnen

(EN 13362, Geosynthetic barriers)



Wasserbausteine

Teil 1 und Teil 2

(EN 13383, Armourstone, Parts 1 and 2)


/DIN EN ISO 14688/ Deutsches Institut für Normung e. V. (Hrsg.)

Geotechnische Erkundung und Untersuchung – Benennung, Beschreibung

und Klassifizierung von Boden

Teil 1 und Teil 2

(EN ISO 14688, Geotechnical investigation and testing – identification and

classification of soil – Parts 1 and 2)


/DIN 18196/ Deutsches Institut für Normung e. V. (Hrsg.)

Erd- und Grundbau – Bodenklassifikation für bautechnische Zwecke


/DIN 52101/ Deutsches Institut für Normung e. V. (Hrsg.)

Prüfverfahren für Gesteinskörnungen – Probenahme


/EAAW/ Deutsche Gesellschaft für Geotechnik e.V.

Empfehlungen für die Ausführung von Asphaltarbeiten im Wasserbau,

EAAW

DGGT, Entwurf, Ausgabe 2008

35


/EAO/ Bundesanstalt für Wasserbau

Empfehlungen zur Anwendung von Oberflächendichtungen an Sohle und

Böschung von Wasserstraßen, Mitteilungsblatt Nr. 85

English version:

Recommendations for the Use of Lining Systems on Bed and Banks of Wa-

terways, Bulletin No. 85 – English translation

Eigenverlag, Karlsruhe 2002

/GBB/ Bundesanstalt für Wasserbau

Grundlagen zur Bemessung von Böschungs- und Sohlensicherungen an

Binnenwasserstraßen, Mitteilungsblatt Nr. 87

English version:

Principles for the Design of Bank and Bottom Protection for Inland Water-

ways, Bulletin No. 88


/Kayser 2005/ Bundesanstalt für Wasserbau

BAW-Brief Nr. 2/05, Zur Handhabung der neuen Norm DIN EN 13383 für

Wasserbausteine und deren Umsetzung in einer Steinbemessung’


/MAG/ Bundesanstalt für Wasserbau

Merkblatt Anwendung von geotextilen Filtern an Wasserstraßen (MAG)

English version:

Code of Practice “Use of Geotextile Filters on Waterways” (MAG)


/MAK/ Bundesanstalt für Wasserbau

Merkblatt Anwendung von Kornfiltern an Wasserstraßen (MAK)‚


/MAV/ Bundesanstalt für Wasserbau

Merkblatt Anwendung von hydraulisch- und bitumengebundenen Stoffen

zum Verguss von Wasserbausteinen an Wasserstrassen (MAV)


/MSD/ Bundesanstalt für Wasserbau

Merkblatt Standsicherheit von Dämmen an Bundeswasserstraßen (MSD)


/RAP Waba/ Bundesanstalt für Wasserbau

Richtlinie für die Anerkennung von Prüfstellen für Wasserbausteine im

Verkehrswasserbau


36


37

/RiReS/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Richtlinien für Regelquerschnitte von Binnenschifffahrtskanälen

BMVBS, Intranet der WSV

/RPW/ Bundesanstalt für Wasserbau

Richtlinien für die Prüfung von mineralischen Weichdichtungen im

Verkehrswasserbau


/STLK 207/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Standardleistungskatalog für den Wasserbau, Landschaftsbau (Leistungs-

bereich 207)

Internetseite der BAW

/STLK 210/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Standardleistungskatalog für den Wasserbau, Böschungs- und

Sohlensicherungen (Leistungsbereich 210)


/TLG/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Technische Lieferbedingungen für Geotextilien und geotextilverwandte

Produkte an Wasserstraßen


/TLW/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Technische Lieferbedingungen für Wasserbausteine


/TR-W/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Verzeichnis der wesentlichen Technischen Regelwerke – Wasserstraßen –


/ZTV-W 210/ Bundesministerium für Verkehr, Bau und Stadtentwicklung

Zusätzliche Technische Vertragsbedingungen – Wasserbau für Böschungs-

und Sohlensicherungen (Leistungsbereich 210)


BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 3.1

Annexes

Annex 3.1: Principles of hydraulic design in accordance with /GBB/

Symbol Item Equation in

/GBB/

Value

LH Development length of the

boundary layer of the ship:

LH = fEL L

(5-18) Factor fEL = 0.8

Aw Secondary wave height coeffi-

cient

(5-47)

(5-43)

0.25; 0.35 for push-tow units

CH Calculation of drawdown at the

stern

(5-29) full: 1.3; empty: 1.5 except1):

Europe ships, full: 1.35 at T/h = 0.625

Very large self-propelled barges, empty:

1.47 at T/h = 0.45

C Drawdown time (5-37) Self-propelled barges (including very

large vessels): 1.7

Europe ships/push-tow units: 1.3

� Coefficient for considering the

wave-generating length of a ship

(5-42) = 0.9

LPris Length of prismatic cross-

section: LPris = fL,pris L

(5-40) Self-propelled barges (including very

large vessels), Europe ships:

fL,pris = 0.8

Push-tow units: fL,pris = 0.9

fB Factor of the influence width (5-8),(5-7) fB = 3

Kss Equivalent sand roughness of the

ship’s hull

(5-18) Kss = 0.0003m

Europe ships: Kss = 0.0005m

Factor for

drawdown

at the bow

Calculation of bow wave (5-28) Factor 1.1

B´B, B*B Coefficient for the frequency of

recurrence, B*B,

stability coefficient, B´B

(6-3),(6-4),

(6-5)

Certain degree of maintenance required,

i.e. unconservative design

B´B = 2.3; B*B= 3.0

SF Shape factor, stone sizing, con-

version of Dn to D

(6-2) SF = 0.65

Shape factor, conversion of Dn to

stone length DTLW (L)

(6-15)

explicit

= 1.8

38

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 3.1

39

Symbol Item Equation in /GBB/

Value

T-profile RT-profile 2) y Distance between the ship’s axis and the axis of the canal

Figure 5.14

Europe ships: 11.75m Self-propelled barges, push-tow units: 10.78 m

Very large self-propelled barges: 10.5 m

Europe ships: 9.86m Self-propelled barges, push-tow units: 8.86 m

Very large self-propelled barges: 8.61 m

n Void ratio of the armour layer (7-2) 50 %

g Acceleration due to gravity g = 9.81 m/s²

’D Angle of internal friction of the dumped stones or other armour layer material

’D, mechanical = ’D,hydraulic = 55o

Note: Push-tow units are assumed to be rigid vessels in the calculations. 1) Linear interpolation between CH = 1.3 and CH = 1.5 2) Eccentricity of the main axis of the profile minus 1.5 m owing to the different behaviour of ships in RT-profiles

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 3.2.1

Annex 3.2.1: Hydraulic loads at 97 % vkrit for standard T-profiles

Regel-Trapez-Profil für 97 % v_krit

leer voll leer voll leer voll leer voll

vkrit [m/s] 3.63 3.04 3.32 2.66 3.27 2.61 3.13 2.58

hu,Bug [m] 0.12 0.36 0.12 0.36 0.08 0.33 0.12 0.35

hu,Heck [m] 0.40 0.46 0.43 0.47 0.44 0.47 0.45 0.47

vrück,u,Bug [m/s] 0.30 1.03 0.34 1.16 0.23 1.08 0.35 1.15

vrück,u,Heck [m/s] 1.30 1.48 1.49 1.63 1.53 1.67 1.58 1.68

umax [m/s] 2.10 2.53 2.46 2.53 2.51 2.52 2.56 2.50

Hsek,q / 2 [m] 0.15 0.10 0.13 0.08 0.18 0.11 0.12 0.08

Hu,Bug [m] 0.20 0.61 0.20 0.60 0.13 0.54 0.19 0.57

Hu,Heck [m] 0.93 0.95 0.97 0.91 0.98 0.91 0.98 0.91

ta,B [s] 3.8 4.5 5.9 7.4 4.6 5.8 6.5 7.8

ta,H [s] 23.1 27.6 33.3 41.5 57.2 71.5 42.1 51.0

vza,B [m/s] 0.05 0.14 0.03 0.08 0.03 0.09 0.03 0.07

vza,H [m/s] 0.04 0.03 0.03 0.02 0.01 0.01 0.02 0.02

fürS = 2650 [kg/m3] Max nur ES und GMS

Min bei t a

Max ohne üGMSMin bei ta

Max aller SchiffeMin bei ta

Symbole:vkrit kritische Schiffsgeschwindigkeit

h u,Bug / hu,Heck mittlere Wasserspiegelabsenkung am Ufer am Bug/Heck

vrück,u,Bug / vrück,u,Heck Rückströmungsgeschwindigkeit am Bug/Heck

umax Geschwindigkeit der Wiederauffüllungsströmung

Hsek,q Höhe der Sekundärquerwelle

Hu,Bug / Hu,Heck Maximalwert der Wellenhöhe am schiffsnäheren Ufer

bei exzentrischer Fahrt am Bug/Heckta,B / ta,H Absunkzeit am Bug/Heck

vza,B / vza,H Absunkgeschwindigkeit am Bug/Heck

üGMS

hyd

rau

lisch

e G

röß

en

ES GMS SV

Hinweis:Bei Übereinstimmung können bis zu drei Markierungen auftreten !!

40


Annex 3.2.2: Hydraulic loads at 97 % vkrit for standard RT-profiles

Standard rectangular trapezoidal profile for 97 % v_krit

empty full empty full empty full empty full

vkrit [m/s] 3.81 3.18 3.48 2.78 3.42 2.73 3.27 2.69

hu,Bug [m] 0.13 0.40 0.13 0.40 0.09 0.36 0.13 0.38

hu,Heck [m] 0.44 0.50 0.48 0.51 0.48 0.52 0.49 0.52

vrück,u,Bug [m/s] 0.32 1.08 0.35 1.21 0.24 1.13 0.37 1.20

vrück,u,Heck [m/s] 1.36 1.55 1.56 1.71 1.60 1.74 1.65 1.75

umax [m/s] 2.02 2.55 2.45 2.57 2.51 2.57 2.57 2.56

Hsek,q / 2 [m] 0.15 0.11 0.14 0.09 0.19 0.12 0.12 0.08

Hu,Bug [m] 0.21 0.64 0.20 0.62 0.14 0.56 0.20 0.59

Hu,Heck [m] 0.97 0.98 1.01 0.94 1.02 0.95 1.01 0.94

ta,B [s] 4.0 4.7 6.2 7.7 4.8 6.0 6.7 8.1

ta,H [s] 22.4 26.8 32.3 40.4 55.0 69.0 40.7 49.5

vza,B [m/s] 0.05 0.13 0.03 0.08 0.03 0.09 0.03 0.07

vza,H [m/s] 0.04 0.04 0.03 0.02 0.02 0.01 0.02 0.02

for

S = 2650 [kg/m3]

Maximum, Europe ships and self-propelled barges onlyMininum at t a

Maximum, without very large self-propelled bargesMininum at t a

Maximum for all shipsMinimun at ta

Symbols:vkrit Critical ship speed

h u,Bug / hu,Heck Average drawdown at bow/stern at the bank

vrück,u,Bug / vrück,u,Heck Return flow velocity at bow/stern

umax Velocity of slope supply flow

Hsek,q Height of secondary transversal waves

Hu,Bug / Hu,Heck Maximum height of bow/stern wave at the bank

for eccentric sailingta,B / ta,H Drawdown time at bow/stern

vza,B / vza,H Drawdown rate at bow/stern

Very large self-propelled

barges (üGMS)

Hyd

rau

lic p

ara

met

ers

Europe ships(ES)

Large self-propelled

barges (GMS)

Push-tow units (SV)

N.B.:Up to three identical values may be marked !!

41

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 4.1-1

Annex 4.1-1: Guidance on how to determine the mean stone size, D50, or the mean

stone weight, G50

The design stone size, D50, or stone weight, G50, must be specified in the invitation to tender. Quality

checks should be carried out on 100 stones to check compliance with the design value. The stones must

be sampled from the armourstones as delivered as specified in /DIN EN 13383-2/ and /DIN 52101/.

G50 can be determined with a sufficient degree of accuracy from the semilogarithmic cumulative curve of

the weighed stones.

It is not possible to calculate D50 exactly as the grading is determined in stages by means of separate

sieves with square perforations. The following method is therefore proposed for the calculation of D50.

The size distribution is determined by using each of the standard sieves available for the range of each

size class (e.g. 45/63/90/125/180/250/360 mm for CP90/250). The percentage, P, in %, passing the sieve

closest to 50 % (lower, Pu; higher, Po) and the corresponding sieve diameters, Do and Du , are used to

determine D50 by means of logarithmic-linear interpolation between the two pairs of values, Pu/Du and

Po/Do (see figure).

Figure: Determination of D50 by interpolation

D50 is determined by log-linear interpolation as follows:

uo

u

PP

P50

u

ou50 D

DDD

42

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 4.1-2

Annex 4.1-2: Cumulative curves for armourstones - classes LMB10/60, LMB5/40, CP90/250

Typical range of variation: Range in which the greater part of the cumulative curve generally lies (this is

purely informative and is not a requirement).

43

BAW Code of Practice: Use of Standard Construction Methods for Bank and Bottom Protection on Inland Waterways, Issue 2008 – Annex 5.2.1-2

Annex 5.2.1-1: Permeable armour layers comprising riprap –

Recommended thicknesses, dD, of armour

layers for slope and bottom protection systems

Recommended armour layer thicknesses a.), dD, for soil types B1, B2, B5, flexible linings b.)

Recommended armour layer thicknesses, dD [m] with embedded toe (embedment depth: 1.50 m)

Slope Bottom

Size class

Density ρS

[kg/m3]

Geotextile Granular filter c.) Geotextile Granular filter c.) CP90/250 3600 0.50 0.50 0.60 0.50

2650 0.60 0.60 0.60 0.60 3000 0.55 0.55 0.60 0.55

LMB5/40

3600 0.55 0.55 0.60 0.55 2300 0.70 0.70 0.70 0.70 2650 0.65 0.65 0.65 0.65 3000 0.65 0.65 0.65 0.65

LMB10/60

3600 0.60 0.60 0.60 0.60

Recommended armour layer thicknesses a.), dD, for soil type B3

Recommended armour layer thicknesses d [m] Dwith embedded toe (embedment depth: 1.50 m)

Slope Bottom

Size class

Density ρS

[kg/m3]


2650 0.70 0.60 0.60 0.60 3000 0.60 0.55 0.60 0.55

LMB5/40

3600 0.55 0.55 0.60 0.55 2300 0.85 0.70 0.70 0.70 2650 0.70 0.65 0.65 0.65 3000 0.65 0.65 0.65 0.65

LMB10/60

3600 0.60 0.60 0.60 0.60

Recommended armour layer thicknesses a.), dD, for soil type B4

Recommended armour layer thicknesses d [m] Dwith embedded toe (embedment depth: 1.50 m)

Slope Bottom

Size class

Density ρS

[kg/m3]


2650 0.80 0.60 0.60 0.60 3000 0.70 0.55 0.60 0.55

LMB5/40

3600 0.60 0.55 0.60 0.55 2300 0.95 0.70 0.70 0.70 2650 0.80 0.65 0.65 0.65 3000 0.70 0.65 0.65 0.65

LMB10/60

3600 0.60 0.60 0.60 0.60

44


45

Explanatory notes:

a.) The recommended armour layer thicknesses apply to trapezoidal profiles and rectangular-trapezoidal

profiles as defined in section 3.3 and take the following factors into consideration:

1.) Minimum thicknesses (see Annex 5.2.1-3) to take account of the following:

ship collision (as per GBB-eq. 6-20)

anchor cast (as per GBB-eq. 6-19)

UV-protection for geotextiles (as per GBB-eq. 6-22)

granular filters (as per GBB-eq. 6-21)

uniformity of the armourstone layer (as per GBB-eq. 6-17) min dD = 1.5 * Dn50 (U)1/2 with U = D60/D10

to ensure stability of the armourstone layer (see section 4 of the article pub-lished in BAW-Brief 2-2005)

2.) Thickness of the armour layer (see Annex 5.2.1-2) required by the

geotechnical design

The verification required in each case is indicated in colour. The armour layer thicknesses cal-

culated for trapezoidal and rectangular trapezoidal profiles in accordance with Annex 5.2.1-2

have been averaged.

The final values obtained for the armour layer thickness have been rounded to the nearest

5/100 [m].

b.) The recommended thicknesses of armour layers placed on flexible linings only correspond to the

stated minimum thicknesses if the groundwater level is lower than the water level in the canal when

lowered by shipping. The safety against uplift must otherwise be verified (see Annex 5.6.2-1).

c.) The granular filter used for the recommended armour layer thickness may be a double mineral filter

(thickness: 2 x 20 cm) or a mixed granular filter (thickness: 30 cm) as specified in MAK.



Documentation of the armour layer thicknesses,

dD, calculated for slopes (with a geotextile)

Armour layer thicknesses, dD, calculated for a trapezoidal profile

0.91

0.79

0.70

0.59

0.81

0.69

0.61

0.510.55

0.460.40

0.320.29

0.240.20

0.16

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

2200 2400 2600 2800 3000 3200 3400 3600 3800

Density of the stones s [kg/m³]

Arm

ou

r la

yer

thic

knes

s d

D [

m]

Soil type 4

Soil type 3

Soil type 2

Soil type 1

CP90/250

LMB5/40

LMB10/60

Trapezoidal profileRiprap

Armour layer thicknesses, dD, calculated for a rectangular-trapezoidal profile

0.94

0.81

0.72

0.60

0.84

0.72

0.63

0.530.56

0.470.41

0.330.30

0.250.21

0.17

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

2200 2400 2600 2800 3000 3200 3400 3600 3800


Arm

ou

r la

yer

thic

knes

s d

D [

m]

Soil type 4

Soil type 3

Soil type 2

Soil type 1

CP90/250

LMB5/40

LMB10/60

Rectangular-trapezoidal profileRiprap

Explanatory notes:

The thicknesses of armour layers on slopes for soil types 1 to 4 and the minimum thicknesses for stone

size classes CP and LMB in accordance with Annex 5.2.1-3 (broken lines) are shown.

A geotextile and an embedded toe (embedment depth: 1.50 m) have been taken into account.

The minimum thicknesses always apply in the case of soil type B5.

In the case of armour layers placed on flexible linings, the minimum thicknesses only apply if the ground-

water level is lower than the water level in the canal when lowered by shipping. The safety against uplift

must otherwise be verified (see Annex 5.6.2-1).

46



Calculated minimum thicknesses

Calculated minimum thicknesses, dD

Minimum thickness of the layer at the bottom

Minimum thickness of the layer on the slopes Density

[kg/m³]

Size class

[-]

D50 grain size

[m] placed on a

granular filter [m]

placed on a geotextile

[m]

placed on a granular filter

[m]

placed on a geotextile

[m]

CP90/250 0.150 0.50 0.60 0.50 0.50

LMB5/40 0.211 0.62 0.62 0.62 0.62 2300

LMB10/60 0.254 0.71 0.71 0.71 0.71

CP90/250 0.150 0.50 0.60 0.50 0.50

LMB5/40 0.202 0.59 0.60 0.59 0.59 2650

LMB10/60 0.242 0.67 0.67 0.67 0.67

CP90/250 0.150 0.50 0.60 0.50 0.50

LMB5/40 0.194 0.56 0.60 0.56 0.56 3000

LMB10/60 0.232 0.65 0.65 0.65 0.65

CP90/250 0.150 0.50 0.60 0.50 0.50

LMB5/40 0.176 0.53 0.60 0.53 0.53 3600

LMB10/60 0.219 0.61 0.61 0.61 0.61

Explanatory notes

The values shown in the table take the following into account:

ship collision: GBB-eq. (6-20)

anchor cast: GBB-eq. (6-19)

UV-protection of geotextile filters (slopes only): GBB-eq. (6-22)

granular filters: GBB-eq. (6-21)

the coefficient of uniformity: GBB-eq. (6-17) min dD = 1.5 * Dn50 (U)1/2 with U = D60/D10

to ensure the stability of the armour layer, see BAW-Brief 2/2005 Formeln wie auf S. 93 links oben

The minimum thicknesses shown are not dependent on the cross-section of the waterway (trapezoidal or

rectangular-trapezoidal profile).

47


Annex 5.2.2-1: Permeable armour layers comprising partially

grouted armourstones – Recommended

thicknesses,dD, armourlayers for slope and

bottom protection systems (with a geotextile)

Recommended armour layer thicknesses, dD

Recommended armour layer thicknesses, dD [m] with embedded toe (embedment depth: 1.50 m) Size

class

Density

ρS

[kg/m3]

Soil type B1 Soil type B2 Soil type B3 Soil type B4 Soil type B5/

flexible lining

2300 0.40 0.40 0.45 0.70 0.40

2650 0.40 0.40 0.40 0.55 0.40

3000 0.40 0.40 0.40 0.45 0.40

CP90/250

or

LMB5/40 3600 0.40 0.40 0.40 0.40 0.40

Explanatory notes:

The recommended armour layer thicknesses apply to trapezoidal profiles and rectangular-trapezoidal

profiles as defined in section 3.3 if a geotextile is used. The armour layer thicknesses calculated in accor-

dance with Annex 5.2.2-2 for trapezoidal and rectangular-trapezoidal profiles have been averaged. The

final values obtained for the armour layer thicknesses, taking the minimum thickness into account, have

been rounded to the nearest 5/100 [m].

The required armour layer thicknesses obtained by calculation are affected only to a very small degree by

the quantity of grout used. The thicknesses recommended in the table therefore apply to all partially

grouted armour layers in accordance with section 5.2.2 in trapezoidal and rectangular trapezoidal profiles

as defined in section 3.3, irrespective of the quantity of grout used. A grout quantity of 50 l/m² was taken

into account in the calculation of the required armour layer weight.

Yellow shading indicates that the minimum thickness applies. The minimum thickness is 40 cm for par-

tially grouted armour layers if stone size classes CP90/250 and LMB5/40 are used, irrespective of the type of

filter. If a granular filter is used, the required armour layer thickness may be reduced by the thickness of

the filter, but must be not less than the minimum thickness of 40 cm. If a double mineral filter (thickness: 2

x 20 cm) is used, the minimum armour layer thickness specified for partially grouted armour layers must

always be complied with, irrespective of the range given in the table.

The recommended thicknesses (minimum thicknesses) of armour layers on flexible linings only apply if

the groundwater level is lower than the water level in the canal when lowered by shipping. The safety

against uplift must otherwise be verified (see Annex 5.6.2-2).

48


Annex 5.2.2-2: Permeable armour layers comprising partially

grouted armourstones – Documentation of the

armour layer thicknesses, dD, calculated for

slopes (with a geotextile)

Armour layer thicknesses, dD, calculated for a trapezoidal profile

0.66

0.52

0.43

0.33

0.43

0.34

0.28

0.22

0.150.12 0.10

0.07

0.00 0.00 0.00 0.000.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

2200 2400 2600 2800 3000 3200 3400 3600 3800


Arm

ou

r la

yer

thic

knes

s d

D [

m]

Soil type 4

Soil type 3

Soil type 2

Soil type 1

Minimum thickness

Trapezoidal profilePartially grouted

Armour layer thicknesses, dD, calculated for a rectangular-trapezoidal profile

0.71

0.56

0.46

0.36

0.48

0.38

0.31

0.24

0.160.13

0.10 0.08

0.00 0.00 0.00 0.000.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

2200 2400 2600 2800 3000 3200 3400 3600 3800


Arm

ou

r la

yer

thic

knes

s d

D [

m]

Soil type 4

Soil type 3

Soil type 2

Soil type 1

Minimum thickness

Rectangular-trapezoidal profilePartially grouted

Explanatory notes:

The thicknesses calculated for armour layers on slopes for soil types 1 to 4 and the minimum thicknesses

for stone size classes CP90/250 and LMB5/40 (broken lines) are shown.

A geotextile, an embedded toe (embedment depth: 1.50 m) and a grout quantity of 50 l/m2 have been

taken into account in the calculations by way of additional weight. The required armour layer thicknesses

obtained by calculation are affected only to a very small degree by the quantity of grout used.

The minimum thicknesses always apply in the case of soil type B5.

In the case of armour layers placed on flexible linings, the minimum thicknesses only apply if the ground-

water level is lower than the water level in the canal when lowered by shipping.The safety against uplift

must otherwise be verified (see Annex 5.6.2-2).

49


Annex 5.2.3: Impermeable armour layers comprising fully grouted armourstones

placed on a geotextile – Required armour layer thicknesses, dD,

against buoyancy

Basis of the calculation:

Safety against uplift a = 1,0

Drawdown za = 0,89 m ( za = Drawdown relevant for

Void ratio n = 50% calculating buoyancy)W = 9,81 kN/m³

V = 22 kN/m³

Maximum value of za in accordance with the parameters given in Annexes 3.2.1 and 3.2.2

Slope (inclination 1:3) Bottom

hW

hWBWu

max. GW

za hW

Impermeable armour layer

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8

Difference in water levels hW [m]

Arm

ou

r la

yer

thic

kne

ss d

D [m

]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s

Fully grouted Impermeable armour layer

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [

m]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s

Fully grouted

g = S

FF

WW

FFWaWA

D

S

VS

and

geotextiledwith

nn

dzh

d

)(0

)()()1(cos

)(

qsekHeckua HHz ,, 2

1

Minimum thicknesses of fully grouted armour layers as a function of the size class and density of the

stones used:

LMB5/40 LMB10/60

s < 3000 kg/m³ 40 cm 50 cm

s ≥ 3000 kg/m³ 40 cm 40 cm

50


Annex 5.6.2-1: Permeable armour layers comprising riprap placed on a geotextile,

with an impermeable lining – Required armour layer thicknesses, dD,

against buoyancy




Void ratio n = 50% calculating buoyancy (see Annex 5.2.3 W = 9,81 kN/m³ for equation))

'Di = 10 kN/m³ (Ton)


Clay liner (dDi=20cm)

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s

Clay liner (dDI=30cm)

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]

Geotextile clay liner GCL (dDi=1cm)

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]

hW

hWBWu

max. GW

za hW

g = S

FF

W

DiDiFFWaWA

D

S

S

and

geotextiledwith

n

ddzh

d

)(0

)()1(cos

)(

The minimum thicknesses specified in Annex 5.2.1-3 must be taken into consideration.

51


Annex 5.6.2-2: Permeable armour layers comprising partially grouted armourstones

placed on a geotextile, with an impermeable lining – Required armour

layer thickness, dD, against buoyancy




Void ratio n = 50% calculating buoyancy (see Annex 5.2.3 W = 9,81 kN/m³ for equation))

'Di = 10 kN/m³ (Ton)

mV ≥ 0,05 m³/m² (= 50 l/m²)

V = 22 kN/m³


hW

hWBWu

max. GW

za hW


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

dD [m

]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s

Partially grouted


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [

m]

Partially grouted


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

dD [m

] Partially grouted


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [m

]

2300 kg/m³

2650 kg/m³

3000 kg/m³

3600 kg/m³

Density s

Partially grouted


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [

m]

Partially grouted


0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8


Arm

our

laye

r th

ickn

ess

d D [

m] Partially grouted

g = S

FF

W

DiDiFFWaWA

D

S

S

Wvv

and

geotextiledwith

n

mddzh

d

)(0

)()1(

)(cos

)(

52

Documents

BAW Code of Practice - Bundesanstalt für Wasserbau (BAW) · BAW Code of Practice: ... Annex 5.6.2-1: Permeable armour layers comprising riprap placed on a geotextile, with an impermeable