Bridges Guidelines for Design and Submission

8/11/2019 Bridges Guidelines for Design and Submission

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Objective

These guidelines are intended to provide minimum geotechnical and structural designrequirements for bridges foundations and super structures to safeguard life or limb, environment,

property and public welfare.

Submission requirements while applying for building permit or no objection certificates for

different types of applications are listed clearly for the consultants to avoid any delay for the

project or abortive work.

Submissions must strictly comply with the enclosed submission requirements and that drawings

and design calculations are checked. Incomplete submissions will be returned without review and

as such CED shall not responsible for any delays to the project. CED reserves the right to levy

additional appraisal fees for checking incomplete and unchecked submissions and this fee shall be

paid by the consultant and not passed on to the client.

The information contained in this document has been compiled for use, guidance and minimum

bridge structure requirements. The Guidelines are aimed to give the bridge engineers a general

idea of the basic requirements for review and check bridge schemes until approval from the

CEDs according to principles and standards, in order to facilitate and speed completion of the

work. It is anticipated that the use of these guidelines will result in a uniform design and

construction of bridges throughout Nakheel projects. Any requests for modifications must be fully

documented and presented to PCFC Civil Engineering Department for review and acceptance.


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Structural Section Procedure - 2007 2

1.0 Seminar Meeting

An overview technical seminar of the proposed structural bridge/tunnel project shall bepresented by the project manager. The session will be open to the representatives of

owner, design consultants, contractor, and local authority staff. Each attendee shall bereceived a hard copy of the presentation, with other publications related to the topics.The seminar agenda should focus on and include the following:

Owner, consultant, contractor, and third party information.

Master plan.

Layout and project location.

Review all existing conditions and requirements.

Traffic, roads, and other initial studies.

Design criteria.

Preliminary plans, sections and elevations.

3-D project selected type.

Constructability and techniques consideration.

Submission requirements & Documents

The following documents shall be used as a guide to be submitted for new bridges andreconstruct or modify an existing bridge. Any proposed temporary bridge also requires abridge permit prior to construction. Documents shall be in standard Acrobat 'PDF' formatunless noted otherwise.

1.1 Documents required to be submitted for project regist ration

As a result of the previously seminar, the preliminary submittal for proposed bridgestructure shall consist of and include the following:

Owner, consultant, contractor, and third party information.

Review all existing conditions and requirements.

Locations and survey sheets.

Preliminary soil investigation and foundation report.

Environmental classifications.

Traffic and roads studies.

Hydraulic study, risk analysis and any other relevant reports.

Preliminary plans, sections and elevations.

Concepts, alternatives and types (Bridge type study report).

Design criteria, structural system, methodology, utilities, construction stages,handling, erection, jacking, tolerances, finishes, access, future maintenances andany other details that may require special attention during schedule.

CEDs review and mark up comments to the submitted project through theowner/consultant for review, revises and registries.


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2.0 Documents required to be submit ted for Signboard NOC:

The Project ID.

Cover letter by the consultant.

Affection plan locating the signboard. Letter of the appointment for both the main consultant and contractor.

Trade licence for both main consultant and contractor.

Signboard detailed drawings as per the typical model prepared by (CED).Circular-19656/2007/MAS.

Design calculation sheets for the signboard and footings.


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3.0 Signboard Typical Model


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4.0 Signboard NOC Work Flow


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5.0 Documents required to be submit ted for Mobilization NOC:

The Project ID.


Affection plan.

Letter of the appointment for both the main consultant and contractor. Trade licence for both main consultant and contractor.


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6.0 Mobilization NOC Work Flow:


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7.0 Basic Requirements (Guidelines) for Bridges Soil Investigation Report:

Soil investigation report for any structure will be mainly based upon itslocation with specified coordinates as per affection plan and geographical

maps from the concerned authorities and also with relevant to theinformation about magnitude of superimposed loads, shape of the bridge,past land use, surface topography, geological features and surfacedrainage.

To specify number of boreholes drilled (one borehole for each pier,abutment or wing wall).

For piled foundations, borings, penetration or other in-situ tests shouldnormally be performed to explore the ground conditions to a depth toensure safety, which normally means 5 times the diameter of the shaft ofthe pile (minimum 5.00 m). However, there will be cases when substantially

deeper soundings or borings are needed. It is also a requirement that theinvestigation depth is greater than the 1.5 times the smaller side of therectangle circumscribing the group of piles forming the foundation at thelevel of the pile toes.

To specify coordinates (x, y, and z), Datums as per DMD for boreholes andto be presented on the site affection plan showing plot limits along withlegend and the north direction. Also neighbouring structures, traffic, utilities,vegetation, hazardous chemicals to be clearly mentioned in a generallayout.

Geological stratum or design borehole must clarify the thickness of eachsoil layer with the characteristic properties:

- c kN/m2(cohesion of soil) and (angle of internal shearing resistance) byproviding direct shear test (Minimum of Two Samples for each layer)

- Unit weight of soil (s) kN/m3(above and below the ground water table)- Active, passive, and at rest earth pressure coefficients (ka, kp, and ko)- Unconfined Compressive Strength (UCS) MN/m2 (Minimum of Two

samples for each rock layer specially when pile foundation is used,enabling the structural designer for calculations of the socket friction andend bearing)

- Pressure meter/dilatometer test must be done if the soil stiffness valuesversus depths are required as and when soil stratum is modeled usingadvanced material model through finite element analysis of thegeotechnical structure.

- Piezo Cone Penetration Test in case for reclaimed soil.

All equipments, materials and procedure associated with the geotechnicalwork should comply with latest editions of relevant standards and codes ofpractice as listed below:


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- BS 1377:1990 Part 9 AMD8264-95 - "Method of Testing for Soils for Civil

Engineering Purposes".- ASTM Volume 4.08 Soil & Rock, where applicable.- BS 5930:1999 - "Code of Practice for Site Investigations".

- BS 1377:1990 Part 3 AMD 9028/96 C l.5, Cl.7 & C1.9 for ChemicalAnalysis of Soil and Water.- BS 1377:1990 Part 2 AMD 9027, Method 3 for moisture content.- BS 1377:1990 Part 1 Cl.7.3 AMD 8258/95 for Particle Size Analysis and

BS 1377:1990 Part 2 Cl.9.2 AMD 9027/96 for test method.- BS 1377:1990 Part 2 AMD 9027, Method 4.3 for liquid limit for clayey soils.- BS 1377:1990 Part 2 AMD 9027, Method 5 for plastic limit and plasticity

index for clayey soils.- BS 1377:1990 Part 2 Cl. 6.5.4 for linear shrinkage.- ASTM D 2938-95 for Unconfined Compressive Strength and sample

comply with ASTM D 4543 01 , Cl. 3.1.- BS 1377: 1990 Part 4 Cl. 7 for CBR test.

- BS 1377. Part 2: 1990 Method 8.3 for Specific Gravity (Particle Density).Method soil samples to be prepared according to BS 1377, Part 1 1990,clauses 7.3 & 7.4.4.

- Sulphate Content of Soil : For Sample Preparation BS 1377: Part 3: 1990(Amd. 9028/96) Cl. 5.2(Acid Extract) / (Water Extract). For Test Method:BS 1377: Part 3: 1990 (Amd./9028) Cl. 5.5 (WaterExtract / Acid Extract).

- Chloride Content of Soil : For Sample Preparation: 8S 1377: Part 3: 1990(Amd. 9028/96) Cl. 7.2.3 (Water Extract) / 7.3.3 (Acid Extract). For TestMethod: BS 1377: Part 3: 1990 (Amd. 9028/96) Cl. 7.2 (Water Extract) /7.3 (Acid Extract).

- pH of Soil: For Sample Preparation: BS 1377: Part 3: 1990 (Amd. 9028/96)Cl. 9.4. For Test Method: BS 1377: Part 3: 1990 (Amd. 9028/96) Cl 9.5.

- Sulphate Content of Ground Water: For Sample Preparation BS 1377: Part3: 1990 (Amd. 9028/96) Cl. 5.4. For Test Method: BS 1377: Part 3; 1990(AMD. 9028/96) Cl. 5.5.

- Chloride Content of Ground Water: For Sample Preparation: BS 1377: Part3: 1990 (AMD. 9028/96) Cl. 5.4. For Test Method: BS 1377: Part 3 1990(Amd. 9028/96) Cl. 7 (Mohr Method).

- Gypsum Content BS 1377: Part 3: 1990.- pH of Ground Water: For Sample Preparation: BS 1377: Part 3: 1990

(Amd. 9028/96) CI.9.4. Test Method: 8S 1377: Part 3: 1990 (Amd.9028/96) Cl. 9.5. (However, it is to mention that calibration

Performing engineering analysis of field and laboratory findings.

The visual description of the geotechnical engineer at site for soil samplesand procedures used for sampling, transportation and storage.

Method of sampling the undisturbed, Split Spoon (for SPT) for disturbedsamples.


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Tabulation of quantities of field and laboratory work, presentation of fieldobservations which were made by the supervising field personnel duringthe subsurface explorations;

Presenting the ground or subsurface conditions and the geology of the site

through the findings of the boreholes giving full details of the strataencountered on boreholes Logs having accurate classification of the soilsaccording to BS 5930:1999. The boreholes Logs must have values used todescribe the relative density of the coarse grained-soils and the quality andthe strength of rock such as:

- Standard Penetration Test (S.P.T) with cone or without- Water content (W.C.) for clayey soils- Liquid Limit (L.L.) for clayey soils- Plastic Limit (P.L.) for clayey soils- Unit weight of soil ( s) above and below the ground water table- Free swell (F.S.) for swelling soils

- Rock Quality Designation (RQD) for rock soils- Total and Solid Core Recovery (TCR & SCR) for rock soils- Unconfined Compressive Strength (UCS) for rock soils

Borehole Log must confirm scale, sample key, legend for type of soil, ends ofstratum and ground water table level

Stating the depths range at which the ground water table was encounteredand mentioning that the ground water table is subjected to tidal weatherseasonal variations or by artificial induced effects. Therefore reconfirmationis recommended prior to any works related to the ground water regime.Standpipe peizometers to be installed inside minimum two boreholes foreach site after drilling and cleaning of drilling mud by clean water flushing tomonitoring the ground water depth.

Earth profile must be plotted using the findings of boreholes by showing inground sections.

Mentioning all the field and laboratory tests achieved in details andillustrating the results properly.

Chemical analysis to study the possible susceptibility of foundationconcrete to aggressive in-situ conditions and corrosivity and thereby to

determine the concrete mix specifications by determining pH, SulphurTrioxide and Chloride content of the soils and ground water. Minimumnumber to be considered is three soil samples from above the ground watertable, and three ground water samples for each plot.

Recommendations for choice and the type of foundation based on thegeotechnical study carried out by the geotechnical engineer and the localexperience in the area.


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Information about the seismicity of the area; Soil Profile Type to beconsidered in the seismic analysis according to (Table 16-J) as per UBC1997, Volume 2, Structural Engineering Design Provisions, Division IVEarthquake Design

Liquefaction analysis in case of reclaimed soil : (CPTU is highlyrecommended)

- Calculation of cyclic stress ratio (CSR, earthquake Load) induced in thesoil by earthquake. The ground motion parameters are: UBC zone class:2A, (Richter Magnitude), M=6.0 & maximum ground acceleration, a =0.20g.

- Calculation of cyclic resistance ratio (CRR, soil strength) based on in-situtest data from SPT (Seed & Idriss) or CPT method (1996 NCEERworkshop on Liquefaction Evaluation).

- Evaluation of liquefaction potential by calculating a factor of safety againstliquefaction from the earthquake load and soil strength.

- (F.S. = CRR/ (1.2-1.5) CSR). There are a potential for liquefaction if theF.S. less than unity, the layer is susceptible to liquefy and the grounddensification or mitigation measures are needed

- Estimation of liquefaction induced settlement.

The Geotechnical Specialist Recommendations for the following items mustbe included in the soil investigation report:

EXCAVATION WORKS

The excavation works should be carried out in accordance with goodconstruction practice and following BS 6031:1981 "Code of Practice forEarthworks".

OPEN EXCAVATION AND PROTECTION

Where space permits and above the water table, sides of the excavation wouldbe necessary to be battered and as a Guide the CIRIA Report No. 97"Trenching Practice" recommends a maximum safe temporary slope of 350 tothe horizontal.


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BACKFILL MATERIALS AND COMPACTION CRITERIA

The material used for backfilling purpose shall be of selected fill composed ofsand/granular mixture free from organic matter or other deterioratessubstances. The Plasticity Index of the backfill material shall not exceed 10%.

The maximum particle size of backfill material shall not exceed 75mm andpercentage passing 75 m Sieve shall not exceed 20%. The organic mattercontent should not exceed 2% and the water soluble salt content shall notexceed 5%. It shall be placed in layers of 150mm to 250 mm compactedthicknesses with each layer not to less than 97% of the maximum dry density.The geotechnical engineer must state that the existing material available in sitecan be used for general backfilling or not after performing the chemicalanalysis of surface soil layer.

RETAINING STRUCTURES

The geotechnical engineer must give recommendation for the most preferableshoring system (if required) and soil parameters must be adopted for thedesign.

DEWATERING

Care should be taken during dewatering to ensure that fines are not removedduring pumping since this could result in unpredicted settlements of thesurrounding ground and associated structures.

PILE FOUNDATIONS

- Geotechnical engineer must recommend a suitable type of pile to use(bored cast-in-situ piles is widely used)

- Geotechnical engineer must provide soil report with schedule showingallowable working Loads in compression and uplift for different pilediameters at different piles toe levels based on findings from thegeotechnical study and factor of safety up to 4.

- The depth of investigation below the design toe level should be at leastfive times pile diameter or 5.0m which is bigger. In areas where this

condition is not satisfied for the design, additional borehole should becarried out to the required depth to reconfirm the continuity of the strata. Itshould be noted that the minimum pile toe level should be at least at depthof two times the diameter of pile socketed in the hard strata in order toconsidering this hard strata in the pile design.

- However, it may be noted that for bored cast-in-situ piles, settlements ofthe order of 1% of the pile diameter is normally required to mobilize fullskin friction whereas full bearing is developed at much higher settlements


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(usually at 10% of pile diameter). Hence the pile capacity will be based onfull skin friction and partial end bearing.

FOUNDATION CONCRETE

Where sulphate attack (from the surrounding soil or ground water table) andchloride attack (from concrete aggregate, mixing water and surroundingenvironment) occur together in high concentration, type of cement providesprotection against the corrosion of reinforcement for foundations. In such casesthe test exposure conditions shall be studied in conjunction with modifiedrecommendations for concrete mix design as using GGBS/Cement 66-80 / 34-20% by weight, or 21% to 35% PFA based on local experience in the gulfregion and CIRIA Special Publication 31(1984).

It may be noted that as per CIRIA Special Publication 31, there is no widely

accepted view on concentration at which chlorides become significant in soil orground water but experience in the gulf region suggested it may be as low as0.05% particularly in situations where wetting and drying or capillary rise effect.

Based on the chemical conditions studied by the geotechnical engineer andthe concrete mix design recommendations BS 8500 & BS 5328:Part1:1997,Tables 7a, b, c.

The likely liquefaction induced effects

- Settlement- Surface manifestation- Lateral spreading or landsliding- Loss of bearing capacity for shallow foundation- Loss of lateral soil stiffness

Mitigation of Liquefaction Hazards


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8.0 Documents required to be submit ted for Soil Investigation NOC:

The Project ID.


NOC for Soil Investigation from DEWA (Water, Electricity) andTelecommunication.

Setting-out plan clearly indicating the bridge alignment , spot levels ofalignment to datum DMD, easting and northing co-ordinates.,etc.

Information on type of the bridge and loading and to be given to the soilinvestigation agency to decide the boreholes depths and numbers in orderto prepare a more accurate report.

Borehole locations and depths shall be marked with reference to buildinglayout. Soil investigation report should be as per guidelines.

Letter of the appointment for both the main consultant and soil investigationagency.

Trade licence for both main consultant and the soil investigation agency.


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10.0 Soil Improvement Guidelines

BACKFILL MATERIALS AND COMPACTION CRITERIA

The material used for backfilling purpose (Maximum 2.00 m) shall be ofselected fill composed of sand/granular mixture free from organic matter orother deteriorates substances. The Plasticity Index of the backfill material shallnot exceed 10%. The maximum particle size of backfill material shall notexceed 75mm and percentage passing 75 m Sieve shall not exceed 20%.The organic matter content should not exceed 2% and the water soluble saltcontent shall not exceed 5%. It shall be placed in layers of 150mm to 250 mmcompacted thicknesses with each layer not to less than 97% of the maximumdry density or 98% in case of road base. The geotechnical engineer must statethat the existing material available in site can be used for general backfilling or

not after performing the chemical analysis of surface soil layer. Sand cone testto determine the degree of compaction or plate load test (ASTM D1194 94)to confirm the bearing capacity with the allowable settlement are acceptabletests for this type of soil improvement.

Soil liquefaction improvement options can be characterized asdensification, drainage, reinforcement, mixing, replacement, VibroCompaction, Vibro replacement (Vibro Stone Columns), deep dynamiccompaction and compaction (pressure) grouting. With regards todrainage techniques for liquefaction mitigation, only permanentdewatering works satisfactory. Use of gravel or prefabricated (Wick)drains, installed without soil densification, is likely to provide pore

pressure relief during strong earthquakes and may not prevent excessivesettlement. Their use should be evaluated with extreme caution.

Deep Compaction (Vibro Compaction)

The Vibro Compaction can increase the in situ density. Increase in soil densityis achieved through compaction by an applied static or dynamic stress. Theadvantage of Vibro compaction is to mitigate liquefaction for depths up to 20.00m.

Confirmation conformity will be tested through CPT (ASTM D 3441-98) to becarried out by pre-agreed soil investigation firms prior to commencement ofground improvement. The CPT shall carried out every 2000 m2 maximum tocompare the results with the post compaction CPT to verify the improvementworks for the same area or as per project specifications if more tests arerequired. Tests must be carried out after sufficient period of compactionrecommended by the soil improvement specialist as the friction between thesoil particles is reduced temporarily allowing particles to deposit by gravity.Locations of CPT to be selected at the central points or at one third themaximum distance between the improved points.


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The compaction pattern will be carried out on a triangular pattern withmaximum grid dimensions of (3.00 5.00) m or as recommended by the soilimprovement specialist. Smaller spacing may be tried in case of not reachingthe specific test result. The re-compaction may be carried out in case of where

compaction criteria were not met.

The criteria of achieved compaction shall be the arithmetic average of the tipresistance profile for the post compaction CPT to be not less than 6.0 MPa.

Plate load test to be carried out in accordance to ASTM D1194 94 StandardTest Method for Bearing Capacity of Soil for Static Load and Spread Footingusing a 2.50 x 2.50 m footing area and settlement of 25 mm maximum at targetbearing pressure 150 kPa.

Safety against liquefaction

The hydraulic fill, loose, fine and saturated sands may undergo liquefaction(experience significant loss of strength due to build up of pore water pressureand subsequent deformation in some locations under the cyclic loading ofearthquakes.

Calculation theory: (Recommended Procedures for Implantation of DMGSpecial Publication 117 Guidelines for Analyzing and Mitigating LiquefactionHazards in California. Implementation Committee, March 1999- Preliminaryscreening of Liquefaction

1. Calculation of cyclic stress ratio (CSR, earthquake Load) induced in thesoil by earthquake. The ground motion parameters are: UBC zone class:2A, (Richter Magnitude), M=6.0 & maximum ground acceleration, a =0.20g.

2. Calculation of cyclic resistance ratio (CRR, soil strength) based on in-situtest data from SPT (Seed & Idriss) or CPT method (1996 NCEER workshopon Liquefaction Evaluation).

3. Evaluation of liquefaction potential by calculating a factor of safety againstliquefaction from the earthquake load and soil strength.

4. (F.S. = CRR /[ (1.2-1.5) CSR). There are a potential for liquefaction if theF.S. less than unity, the layer is susceptible to liquefy and the ground

densification or mitigation measures are needed. Minimum factor of safetyaccepted is 2.50.

Estimation of liquefaction induced settlement.


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The likely liquefaction induced effects:

Settlement:

Differential settlement in the range not less than the maximum liquefactioninduced settlement should be expected and considered, if surface footingsexist and no improvement is done.

Surface manifestation:

Surface manifestation such as sand boils or ground fissure may be occurredduring earthquake shaking at the ground level. It is emphases that settlementmay occur, even with the absence of surface manifestation. The evaluating of

the potential for ground cracking and sand boils (Ishihara, 1985) is based onthe thickness of the potentially liquefiable layer and the thickness of the non-liquefiable crust.

Lateral spreading or landsliding:

Such spreads can occur on gently sloping ground or where nearby drainage orstream channel can lead to static shear biases on essentially horizontal ground(Youd, 1995).

Loss of bearing capacity for shallow foundation:

The Implementation Committee recommends that the top of the potentiallyliquefiable layer be at a depth greater than where the induced vertical stressesin the soil are less than 10% of the bearing pressure imposed by thefoundation. There are no recognized analytical methods to evaluate the loss ofbearing capacity at this time. The Implementation Committee recommends thatIshiharas method of analysis of surface manifestation to be used for shallowfoundations.

Loss of lateral soil stiffness:

Loss of lateral soil stiffness has a greater effect on design of piling and shoringworks. Negative skin friction for the entire uncompacted hydraulic fill to beconsidered during design of the pile compression working load. The pile shallbe considered not constrain laterally along the all undensified layer in the pileanalysis in both vertical and lateral analysis. Lateral load to be considered dueto ground motion from earthquake (0.2g).


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Mitigation of Liquefaction Hazards:

Studies by (Lai 1988) indicate that in the presence of liquefiable clean finesands in area of softening due to seepage flow occur to a distance beyond theimproved ground on the order of two-thirds of the liquefiable layer thickness.


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11.0 Documents required to be submit ted for Soil Improvement NOC:

The Project ID. Cover letter by the consultant.

Soil Investigation Report.

NOC for Soil Improvement from DEWA (Water, Electricity) andTelecommunication.

NOC from BU Developer for Soil Improvement.

The soil improvement specialists detailed method statement approved bythe consultant.

Method of confirmation of the improvement.

Letter of the appointment for both the main consultant and soil improvementspecialist.

Trade licence for both main consultant and the soil improvement specialist.


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12.0 Soil Improvement NOC Work Flow:


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13.0 Documents required to be submit ted after Soil Improvement along with

the piling submission:

Pre- CPT plots in the vicinity of Post-CPT locations as per guidelines.

Post CPT plots.

Locations of Post CPT plots.

All CPT plots to show the followings:- Diagram of cone resistance qc versus depth.- Diagram of friction resistance fs versus depth.- Diagram of friction ratio Rf = fs / qc .- Diagram of pore water pressure versus depth.

Plots Post CPTs against target design line (qc = 6 MPa)

Liquefaction analysis complying the guidelines, calculating the factor of

safety against liquefaction and studying if the soil is susceptible toliquefaction or not after performing the densification.

Sandy Soils liquefaction performance curves.

Summary of CPT soil characterization.

Settlement analysis for each CPT location for a bearing capacity of 150kN/m2 at one meter below the post compaction location ground level with asettlement less than 25 mm to be achieved throughout the improved areausing Schmertmann (1974) and Priebe (1995).

Plate load test confirming the proposed bearing capacity the the expectedsettlement.

Level survey to be submitted before and after improvement.


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14.0 Documents required to be submit ted for Preliminary Test Pile NOC:

The Project ID.


The soil investigation report as per guidelines. NOC from DEWA (Water, Electricity) and Telecommunication.

Guarantee letter from the consultant that piles are adequately designed towithstand all critical load combinations.

Letter of the concept approval of the architectural drawings from CED.

Design calculation sheets for the preliminary test pile prepared by the pilingsub-contractor, approved by the consultant and comply with JAFZAguidelines for piling design.

Detailed design and work shop drawings include the location of thepreliminary test pile in plan with respect to the working piles, pilesdiameters, piles working loads, piles testing loads, net pile length, piles cut-off levels, platform level, piles toe levels, steel reinforcement details inlongitudinal and cross-sections showing details of overlapping, lateral ties,concrete cover and spacers.

Detailed method statement for piles execution contains the equipmentsused, working platform, setting out, placing of the temporary casing and itslength if any, drilling of piles borehole, cleaning of pile base, installing ofreinforcement cage, concrete casting, piling records, .., etc.

Detailed method statement for the static load tests including test setup,applying load method, reaction system, measurements of pile movement,loading cycles, increments, durations and design of kentledge or eitheranchors or tension piles. All jacks, pressure cells, dial gages, and otherequipments calibration certificates used in testing to be submitted.

Submitting of the method statement of all other types of tests will beconducted on the same test pile before and after the static test.

Letter of the appointment for both the main consultant and the pilingspecialist.

Trade licence for both main consultant and the piling specialist.

Curriculum Vitae of the Resident Engineer for the Lead Consultant and thepiling Specialist, who shall be accredited by CED on both BLUE (BuildingRegulations & Design Guidelines) and GREEN (Construction Materials &Quality Control Guidelines) code.


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15.0 Preliminary Test Pile NOC Work Flow:

Received by Permit Administration

and uploading

Request sent by

consultant

Procedure of Structural Division

Structural Division

Feedback in respect of

Compliance of required

documents

Preliminary Test Pile NOC

If the submission is

complete

Consultant will be intimated

Via E-mail for payment and collection

If the submission is

incomplete


will be provided By

Permit Administration

Consultant will be intimatedalong with the process of


(The process takes 6 working

days starts from the acceptance)

Any missing document,

the whole submission will

be returned back for re-

submission

Assign the submission to

the concerned engineer for

review then feedback the

adminstration

Any major comments the engineer

will forward the comments thru the

administration to the consultant after

discussing the same with the Headof the Structural Division

Administration will forward

the documents for the final

signatures to the

appropriate authorised

signatories.


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16.0 Design Guidelines for Bridge Piles

Imposed Loads on Bridge Piling:

o Dead and live loads on the super-structure.o Dead Load of the super-structure.o Earth pressure (including surcharge pressure) on abutments and wig

walls.o Creep and shrinkage of the super-structure.o Temperature variations in the superstructure.o Traffic impact and braking forces on the bridge deck (longitudinal

and transverse).o Wind and earthquake forces on the super-structure.o Impact from vehicle collision, locomotive and rail wagons (if any).o Construction loads including falsework.o Differential settlement between piers or between piers and abutment

in longitudinal and transverse direction causing relative rotation of upto 1 in 4000 for continuous deck bridges or simply supported span.The expected value to be within 1% of the pile diameter.

o Piles of over-water bridges are required to withstand lateral forcesfrom current drag and wave action, pressure from floating flooddebris, and impact from vessels straying from the designatednavigation channels.

o The profile of the current velocity with depth varying from amaximum at the water surface to a minimum at bed level must beconsidered in relation to the bending moments on piles in deep fastflowing channels or lakes. Current- induced oscillation should bestudied.

o Calculation of the lateral deflections at the pile head level is required,which can induce bending of the bridge super-structure in thehorizontal plane.

o The depth of the scour below the sea bed around piles at times ofpeak flood must be estimated to calculate the bending moment dueto the current drag forces and wave action on piles. The scour isgeneral from changes in bed levels across the width of the channel,local scour around the pile, and formation of troughs in sand waveswhich move downstream with the passage of the flood.

o Impact of ships for navigable water ways in case of no massivestructure can absorb the impact or independently fender piles.

The permissible service stress should not exceed 25% of the specifiedcube strength at 28 days as per BS 8004 : 1986, Section 7.4.4.3.1

The ultimate axial load should not exceed the value of N given in BS8110, Part 1 : 1997, Section 3.8.4.3

The minimum percentage of reinforcement is according to Table 3.25 of BS8110, Part 1 : 1997


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Pile bearing capacity calculations as per BS 5400, BS8004, BS8081, EC7and to appropriate text books, such as Tomlinson (1995), Fleming et al(1992) or CIRIA Report 181 for different types of soil taking the nature ofshaft resistance when using bentonite, water or using full length casing intoconsideration. Other considerations may be applied for design under

seismic loading and liquefaction. Negative skin friction should be added tothe applied load in case of penetration of reclaimed soil.

In BS 8004: 1986 a single lumped factor of safety between 2 and 3 isrecommended to be applied to the total ultimate pile resistance (shaft andbase). Tomlinson (1995) suggests that a single factor of 2.5 will normallyrestrict settlement of a single pile at the working load to 10 mm. Even forULS calculations, lumped factors combine several, often unrelated,uncertainties. Therefore there is some logic in trying to assign separatepartial factors to different steps of the design process and to consider thesource of uncertainty more directly. In case of considering the soilliquefaction including lateral spreading, negative skin friction and buckling,

FOS (3 - 4) can be used.

Considering horizontal force and bending moment resulting from out ofposition by 75 mm in horizontal direction at working level, and out of theplump (verticality) by 1:75 according to BS 8004: 1986, Section 7.1 and7.4.5.4.8. In case of the pile head is fully restrained by pile caps or raft,considerable amount of the eccentric moment may be distributed andabsorbed by the restraining system.

Considering lateral load on pile resulting from the vertical compression loadnot less than 5 % of the value of the vertical compression load, to bechecked not less than the lateral load evaluated from the super-structureanalysis.

Elastic analysis to check the adequacy of the pile to resist the lateralloading and bending moment using (Reese & Matlock) is required.

In case of the pile inserted into liquefiable soil, the pile can buckle and pushthe soil; it is not necessary to invoke lateral spreading of the soil, whichpushes the pile. This instability depends on the slenderness ratio (Leff/rmin)of the pile exceeding a critical value in the liquefiable region. Once thesurrounding soil has its effective stresses eliminated by an earthquake, asusceptible pile starts to buckle in the direction of least elastic stiffness. If

the soil around the pile remains liquefied for long enough, the pile will suffergross deformations and the superstructure will either tilt or deform. Codesof practice need to include a criterion to prevent buckling of slender piles inliquefiable soils. The designer should first estimate the equivalent length forEulers buckling. It is then necessary to select a pile section having amargin of safety against buckling under the worst credible loads.

Checking for stirrups for the pile is according to Table 3.8 of BS 8110, Part1: 1997. Lateral ties should not closer than 150 mm centers so that placing


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of concrete is not impeded as per BS 8004 : 1986, Section 7.4.4.4.2. Shearstrength may be increased in case the effect of the compression load istaken into consideration.

Checking for bond length of steel bars extended into the foundation to be

according to Table 3.27 of BS 8110, Part 1: 1997.

Concrete below ground shall be designed as water excluding, both toprevent ingress of water and also to prevent aggressive ground waterpenetrating the concrete, causing corrosion of the reinforcement. Thedesign shall be to BS 8102 Type B using BS 8007 with a 0.20 mm crackwidth.

Concrete mix design should be according to the sulphate and chloridecontents reported at the soil investigation report for both soil and underground water, and according to BS 8500 & BS5328.

Piles inserted in water ways are exposed to potentially aggressiveconditions in the atmosphere and they may be subjected to abrasion fromshifting sand or shingle. Durability of the concrete must be studied as wellas the effect of the bacterial action and bacteriological corrosion, such ascontaminable tidal mud flats. Steel piles must be protected from corrosionsby the cathodes protection.

Settlement calculations under the working loads to be provided. Theexpected value to be within 1% of the pile diameter.

Pile skin friction in sand should be reduced by 50 % in case of usingbentonite as drilling slurry.

For friction piles the spacing should be not less than three times the pilediameter, and not less than twice the pile diameter for end bearing piles asper BS 8004: 1986, Section 7.3.4.2.

For tension piles resisting uplift or end bearing piles installed from groundlevel until deep bedrock, the reinforcement should normally be carried downfor the full length. According to BS 8004 : 1986, Section 7.4.5.3.2

The longitudinal reinforcement should extend at least 1.00 m below the

bottom of casing so that movement of the reinforcement during extraction ofcasing is minimized. BS 8004 : 1986, Section 7.4.5.4.5

A minimum additional allowance of 40 mm should be added to coverrecommended in Table 3.4 of BS 8110, Part 1: 1997.

Cover spacers may be pre-formed plastic to be used for the pile. Thespacers should be threaded to lateral stirrups. The spacers should be fixedat a longitudinal spacing of not more than 2.0 m with minimum of three


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spacers to be placed in each row. One set should be fixed at the pile cut-offlevel and one at approximately 1.0 meter from the toe of the cage.

* Points to be checked during construct ion:

- If betonite slurry is used so its density should be less than 1.10 g/mL; theviscosity as measured by the Marsh Cone should be within a range of 30 to90 seconds, and the 10 min. gel strength to be in the range of 1.4 N/m2 to10 N/m2. The pH value should be maintained within a range of 9.5 to 12.BS8004: 1986, Section 6.5.3.8.1.

- The geophysical properties of the bentonite slurry should be re-establishedprior to the commencement of concreting operation. A submersible andcirculation pumping system or air lifting system may be utilized for thispurpose.

- If extensive bentonite slurry loss occurs during drilling, the drilling will be

stopped immediately. The bore will be backfilled with the excavatedmaterial in order to create a plug surrounding the pile shaft. Re-drilling willthen take place. If further fluid loss or shaft collapse occurs, the bore will beimmediately backfilled with low strength, lean mix concrete prior to anyfurther excavation taking place.

- Before Installing steal cage and casting concrete when reaching the pile toelevel, loose and remolded material and debris will be removed with thedrilling or cleaning bucket.

- High slump concrete of specified grade should be used according to Table14 of BS 8004 : 1986

- For a continuous assurance of concrete quality and integrity, concreteshould be poured to minimum 1.50 m above the theoretical pile cut-off

level.- Casting of piles shall be performed as a continuous operation. The concrete

should be designed to remain workable for a minimum of three hours fromthe time of the batching to the time of placement into the pile.

- The concrete shall be placed by tremie tube method; the tremie size will notbe less than 150 mm. The tremie pipe will be inserted at the centre of thepile to reach up to the toe. The top of the tremie pipe will be connected to afunnel. The concrete shall be delivered directly from the transit mixer to thefunnel. The tremie pipe will be lifted 100 mm above pile toe level prior toconcreting. While concreting the length of the tremie pipe will be shortenedif necessary but the tremie pipe will be maintained full time into the concreteof at least 2.0 m length.

- Continuous supervision on site by engineer and the contractor is alwaysnecessary to ensure that the piles are properly.

- All plant materials and operations employed in the formation of a pileshould be such as to ensure that the completed pile is of the full crosssection. Where reinforcement is used, care will need to be taken to ensurethat it is not displaced or distorted during the formation of the pile. Effectivemeans should be employed to keep it in place with correct cover andalignment during concreting of pile.


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PILES TESTING

Piles testing shall conform to the following minimum requirements:

a) At least one for each pile diameter non-working pile shall be tested to 200% ofthe piles working load. BS 8004:1986, Section 7.5.5 or ASTM D 1143-89. (Tobe submitted with the pile design calculation sheets before executing anyworking piles at the piling design approval stage), Osterberg cell can beaccepted only in the preliminary test.

b) 1 % of total number of working piles and minimum one test for each pilediameter (group/type) shall be statically tested to not less than 150 % of thepiles working load. BS 8004:1986, Section 7.5.5 or ASTM D 1143-89.Osterberg cell can be accepted only in the preliminary test.

c) 5 % of the total number of working piles shall be tested using high straindynamic method to not less than 150 % of the piles working load. ASTM D4945-89

d) 10% of the total number of working piles shall be tested using cross- holesonic core logging testing method for pile diameter equal or more than 600mm.ASTM D 6760-02

e) 100 % of working piles shall be tested by using low strain dynamic integrity testand repeated again for only piles statically tested. ASTM D 5882

f) Pile instrumentation test should be performed for one test pile during staticload test for piles have diameters of 1000 mm or more as per projectspecifications.

g) Static laterally loaded piles test should be conducted at cases that lateral loadsare major value in the design as per project specifications.

h) Static tension pile test should be conducted at which using tension piles toresist uplift as per project specifications.

i) 10 % of working piles boreholes/rig and all preliminary & working test piles oras per project specifications if more tests are required to be selected randomlyand tested by mechanical calliper logging ( ASTM D 6167 97 & ASTM D5753 95e1).

j) One set of tests to the steel reinforcement for mechanical and chemicalproperties for each bar diameter at the start of the job and every 200 tons ofsteel delivered to the site. Every consignment of steel shall have millcertificates to be submitted from independent laboratories approved byconsultant. BS EN 10080

k) Cube tests results for compressive strength after 28 days comply with BS1881-116, EN 12390-3.

l) Durability test for concrete samples should be conducted each 500 m3 of thecast concrete or as per project specifications if more tests are required. (BS1881-122 ,BS 1881-124, BS 1881-208, ASTM C 1202 & EN 12390-8)Durability limits for piles, raft slab, tie beams, retaining walls & pile caps (Sub-structure): Maximum water absorption =1.5% at 28 day, Maximum waterpenetration =10 mm at 28 days and Rapid chloride permeability =1200coulombs at 28 days (max.).


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Documents to be submitted for the Osterberg-Cell test: (Preliminary Non-Working Piles)

a) Soil investigation report approved by the consultant.b) Pile design calculation sheets approved by the consultant.c) Detailed design and work shop drawings include piles numbers in plan, piles

diameters, piles working loads, piles testing loads, net pile length, piles cut-offlevels, platform level, piles toe levels, steel reinforcement details in longitudinaland cross-sections showing details of overlapping, lateral ties, concrete cover,spacers, details of attached O-Cell assembly and splice with subsequent rebarcage sections as well as the embedded compression telltales below andabove the O-Cell. In addition, shop drawings should contains a scheduleshowing the top casing level, coordinates, toe level and cut-off level for eachpile.

d) Detailed method statement for piles execution contains the equipments used,working platform, setting out, placing of the temporary casing and its length ifany, drilling of piles borehole, cleaning of pile base, installing of reinforcementcage, concrete casting, piling records, .., etc.

e) Pile history report.f) Concrete testing report.g) Method statement and results of cross-hole sonic testing to be performed on

the tested pile by O-Cell method before the loading test.h) Method statement and results of pile using low strain dynamic integrity testing.i) Detailed method statement and schematic section for the test pile including

assembly, installation, instrumentation, method of measuring compressionbelow and above the O-Cell, method of monitoring the top of pile movementand the reference beam, the strain gauge configuration for measuring the sideshear transfer of the pile above the O-Cell, details of the galvanized ironedpipes installed from the top of the pile to the top of the bottom plate of the O-Cell to vent the break in the pile formed by the expansion of the O-Cells and

method of measuring the pressure applied to the O-Cell.j) Correction reference of measures for temperature effects.k) The results report must include the followings:

Field data and data reduction.

Reference beam monitoring.

Tilt in the O-cells openings.

Strain gauge microstrain versus O-Cell load.

Average net unit side shear values.

Osterberg Cell load-movement curves.

Equivalent top load curve.

Strain gauges load distribution curves.

Upward net unit shear curves. Unit end bearing curve.

Construction of the equivalent top loaded load-settlement curve.

Hyperbolic curve fit.

Pile stiffens estimation.

Pull-out load-displacement curve for tension piles.

O-Cell and instrumentation calibration sheets.


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17.0 Documents required to be submi tted for Bridge Piling Works BuildingPermit:

The Project ID. Cover letter by the consultant.

The detailed soil investigation report as per guidelines.

NOC for Construction from DEWA (Water, Electricity) andTelecommunication.

Guarantee letter from the consultant that piles are adequately designed towithstand all critical load combinations.

Letter of the concept approval of the Master plan / Architectural drawingsfrom CED.

Third party review report.

Preliminary static pile tests results approved by the consultant and Thirdparty.

Concrete mix design complies with regulations.

Affection Plan approved by the BU developer.

Copy of the shoring NOC (if any) as well as shoring elements test resultsapproved by the consultant.

Soil Improvement test results report (if applicable) approved by theconsultant.

Design calculation sheets for piling works prepared by the piling sub-contractor, approved by the Consultant, Third Party and comply with theguidelines for piling design.

Detailed design and work shop drawings include piles numbers in plan,piles diameters, piles working loads, piles testing loads, net pile length,

piles cut-off levels, platform level, piles toe levels, steel reinforcementdetails in longitudinal and cross-sections showing details of overlapping,lateral ties, concrete cover and spacers. In addition, shop drawings shouldcontains a schedule showing the top casing level, coordinates, toe leveland cut-off level for each pile.

Pile caps layout along with pier columns and walls locations withdimensions.

Pile caps sections shows thicknesses and bottom levels in relations todatum.

Stability analysis for wind, seismic and lateral loads and all other types ofloading as per the guidelines.

Loads on piers including wind, seismic and lateral moments are to bemarked on the pile cap layout for critical load cases.

A softcopy of the model in a CD as per JAFZA Bridge guidelines as well asall active excel sheets used in calculation and design shall be submitted.

Detailed method statement for piles execution contains the equipmentsused, working platform, setting out, placing of the temporary casing and itslength if any, drilling of piles borehole, cleaning of pile base, installing ofreinforcement cage, concrete casting, piling records, .., etc.


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Detailed method statement for all static load tests including test setup,applying load method, reaction system, measurements of pile movement,loading cycles, increments, durations and design of kentledge or eitheranchors or tension piles. All jacks, pressure cells, dial gages, and otherequipments calibration certificates used in testing to be submitted.

Detailed method statement for dynamic load test and checking the pilereinforcement to withstand the tensile stresses generated by the test.Details of the provided hole in the centre of the pile top for placing the testrod and the prepared pile head contains a steel bursting ring to resistdynamic impact should be submitted for approval.

Detailed method statement for cross-hole sonic logging test using minimum4 tubes for piles diameters 800 mm and more. Access tubes shall be filledwith clean fresh water within one hour of concrete placement and testshould be done within 45 days after concrete placement to avoid concretede-bonding for steel tubes (10 days for PVC tubes). Tube tops shall becapped immediately after installation to prevent entering of debris to theaccess tubes.

All other piles integrity tests method statements including trimming andcleaning at the final design cut-off level to be submitted for approval.

Quality control, quality assurance, safety and health plans to be submittedfor approval.

Letter of the appointment for both the main consultant and the pilingspecialist.

Trade licence for both main consultant and the piling specialist.

Curriculum Vitae of the Resident Engineer for the Lead Consultant and thepiling Specialist, who shall be accredited by CED on both BLUE (BuildingRegulations & Design Guidelines) and GREEN (Construction Materials &Quality Control Guidelines) code.


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18.0 Bridge Piling Works Building Permit Work Flow:


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19.0 Documents required to be submit ted after completion of Bridge piling

works:

Each pile history report (periodic during construction)

Static load tests results approved by the consultant, accompanied withinterpretation of the ultimate pile load using Brinch Hansen Method andModified Chin Method, 1970.

Dynamic load tests results approved by the consultant.

Cross-hole sonic logging tests results showing signal peak diagram as afunction of time versus depth, computed initial pulse arrival time versusdepth, computed relative pulse energy versus depth, each pair tube logidentification and orientation and statement whether the tested piles containany integrity problems, local damage, cracking, voids, poor qualityconcrete, honeycombs, contamination or soil/slurry intrusions. All the

interpretations shall be based on CIRIA guide 144 "Interpretation of PileIntegrity Testing". Defective zones are defined by an increase in arrival timeof > 20% relative to the arrival time in a near by zone of good concrete.

All Integrity tests reports approved by the consultant indicating any nickingor enlargement depth in the pile shaft cross-section or concrete quality.

Mechanical calliper logging test report indicating the borehole diameter,shape, roughness, and stability of the drilled borehole.

All concrete cube compressive strength after 28 days of concrete placing.

Results of the concrete durability tests approved by the consultant.

All steel reinforcement tests results to be submitted from independentlaboratories approved by consultant and accompanied with mill certificates.

As built piles coordinates drawing indicating the deviation from the designcoordinates and the resulting difference.

Consultant certificate accepting piles deviations from the designcoordinated when they be within the allowable tolerance accepted(maximum out of position tolerance for single pile = 75 mm, maximum out

of plump for single piles 1:75, and maximum out of position tolerance forgroup piles = 100 mm), otherwise the consultant must replace orsupplement by one or more additional piles or to amend the design of thepile cap, tie beams or the raft. BS 8004: 1986, Section 2.4.4 and 7.4.2.5.4.

Undertaking letter or grantee letter from the piling sub-contractingconcerning piling works are executed complying the approved drawingsand specification and the full responsibility or grantee for piling works up to50 years.


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20.0 Bridge Super-Structure

Documents required to be submit ted for the superstructure permit

The final submittals for bridge structure, which are based on the approved preliminarysubmittals and project registration, shall consist of and include the following:

Project ID

Cover letter for final bridge permits submission.

Affection plan / Lease drawing.

Bridge alignment approved/Certificated by the business unit.

Letter of appointments for the Consultant and main Contractor from the Owner.

Letter of appointments for the third party reviewer.

Trade Licence of the Consultants and Contractor.

Trade Licence of the Third party reviewer.

NOCs from CED-EHS, DEWA, Telecom, RTA and other authorities for thespecific type of infrastructure.

Curriculum Vitae of Resident Engineers for the project from the Consultant andthe Contractor.

Geometry, electricity and utility documents.

Final detailed soil Investigation report including seismic soil parameters &constructability consideration with recommendations for foundation, concretedurability and chemical analysis reports.

Proposed concrete mix specifications.

Structural documents consisting:a. Titles sheet.

b. Landscaping, earthwork limit lines, treatments andprotections.

c. Design Criteria used for the project.d. Project Brief highlighting the structural system, design

philosophy and any special considerations used.e. One full set of drawings signed and stamped by the

Consultants Engineer. Drawings shall also be signed by thethird party reviewer if the project requires third party review.

f. Computer analysis model files and active used spread sheets.g. Third party reviewers report for the project.h. Design calculations arranged in a sequential order according

to the design elements.

i. Complex component and any other critical issues.

The bridge structural design calculation shall be furnished for all parts of thestructure, contains references to the applicable specification, and at least shouldinclude the followings:

1 Plan, geometry, cross sections and elevations.2 General notes sheet.


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3 Philosophy, assumptions, structural system and design criteria.4 Considered normal and abnormal loadings (e.g. multi-directional

earthquake, wind gust, flood, vessel collision, fire, blast, adjacentstructures, traffic overload and accidents, etc.)

5 Section properties.

6 Material properties.7 Allowable stresses.8 Losses.9 Longitudinal structural actions.10 Pre-stressing arrangement and sequence.11 Check of stresses.12 Strength design check.13 Fatigue and serviceability checks.14Transverse actions.15 Stiffeners, joints, strips, deviators, diaphragms and Local effects.16 Splices, corbels, anchorages and crosshead design.17Superstructure design.

18 Camber and deflections.19 Bearing loads and movement.20 Piers loads and buckling.21Substructure design.22 Abutments, wings, approach slab, retaining walls and footing design.

CEDs review and mark up comments to the submitted project through theowner/consultant for review, revises and permit. The Consultant has full responsibility forthe accuracy and completeness of the plans and relevant designs, and other documentsthat may be needed for the project. Cooperation, assistance, control and approvals byCED will not relieve the consultant of this Professional Responsibility.


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Certif icates required from Third Party along with final superstructure permit.

The Consultant shall prepare and deliver the above final submissions and otherdocuments to CED for approval. Permit applications shall include the following certificate

issues:

1- The Consultant must have a quality control plan that establish an independentlycheck, coordination and corrections. The Consultant shall confirm that: allstructural drawings have been checked with CED Bridge Design Guidelines andCode regulations. The structural calculations have been prepared by Engineers

. and it has been checked by Engineer ....

2- In case of pilling permit submission, the Consultant shall confirm that: the finalpiles reactions based on any future modifications due to the design developmentprocess will not exceed the current pile capacity or strength of the structuralmembers.

3- Third party reviewer certificates should be submitted with a summary of findings,comments and action sheet results. Also, he shall confirm the followings:

The project design documents are complete and accurate.

The project meets the appropriate solution for existing conditions.

The methods of analyses are reasonable and accurate according to CEDGuidelines and accepted engineering standards.

The project cost and benefits are in balance.


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21.0 Bridge Permit Work Flow


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22.0 Bridge Design Guidelines

22.1. Introduction

The issuance of these guidelines comes in the framework of the CED's publicationsdesigned to facilitate and simplify procedures, which became available to all publicinterest. So, this document is an integral part of CEDs other regulations and designguidelines (blue, green, yellow & red Codes). These guidelines are based on International& National Codes of Practice, Design Manuals, Technical Books and Papers.

22.2 Design Outcome

The design shall meet all relevant standards for safety, durability, corrosion, fire

resistance, and serviceability. The project must be in accordance with CED regulations,applicable codes, current successful engineering practices and specifications. Thedesigner shall investigate alternative systems and shall achieve optimized economicaland constructible solution.

22.3 Applicable Codes

The standard American Association of State Highway and Transportation OfficialsAASHTO LRFD (Load and Resistance Factor Design) bridge specifications- with latesteditions- shall be permitted for the purpose of structural design, detailing and

construction. All structures shall satisfy recommendations of the Dubai Municipality,RTA, JAFZA and other relevant statutory authorities. Other technical codes shall besubmitted for review prior to adopting in the design scheme.

The following parameters shall be considered:

1- Consider site layout, elevations, economics, aesthetics, access, maintenance andconstructability when deciding the bridge type.

2- Unless otherwise specified, 100 year design life-span of the bridge structure shallbe adopted. However, important bridges would have a longer design life (e.g. 150or 200 years).

3- All analyses shall be performed assuming no benefit from the effect of tire contactarea, wearing surface, stiffening of traffic railing barrier, passive soil resistanceand advanced soil modelling.

4- The slab/wall thickness must not be less than 200 mm.5- All bridges shall be designed for a minimum future 50mm wearing surface.6- Wind loads shall be based on wind velocity of 45 m/sec.


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7- Zone 2 corresponding to acceleration coefficient, A, equals 0.15 shall be adoptedfor seismic analysis. In the reclaimed soils, to account for soil amplification, theacceleration coefficient shall be equalled 0.19.

8- For critical bridges, multi-mode spectral analysis must be checked. The number ofmodes included in the analysis should be at least three times the number of spans

and capture at least 90% mass participation.9- For bridges with closely-spaced vibration modes, instead of the CQC or SRSS

methods, an alternative method of combining the modal effects, such as an"Absolute Sum", should be used.

10-5% damped response spectra in concrete seismic design can be used.11- 27oC in body-mean-temperature shall be used, adopting long-term modulus of

elasticity of concrete.12-Thermal stresses due to temperature gradient to be computed using Zone-1

temperature values.13- Thermal stresses due to continuity effect shall be calculated by considering

temperature difference of 12oC between the extreme fibers.

14-Unless otherwise specified, the site coefficient for soil profile Type II can be used.15-P-Delta effects on long period structure should be considered. Check for global

stability should be part of the design process.16- Develop camber diagrams taking into account the casting stages. However, girder

deflections shall be monitored during pouring operations. It may be necessary toprovide temporary supports at certain locations.

17-For segmental construction, relative displacement should not be permittedbetween joints under service loading.

18-The potential for soil liquefaction, lateral spreading, and slope movements shall beinvestigated and accounted for in the design and construction.

19-Unless otherwise noted, differential settlement of minimum 1% pile diameter shallbe adopted. For walls, settlements in both longitudinal and transverse directionsmust be considered.

20-For critical and essential bridges, design vehicular live load is in accordance withLRFD HL-93 design live load magnified by a factor of 1.50. For other bridges, afactor of 1.00 applied to the LRFD HL-93 design live load (design truck or tandem,with design lane load) can be used.

22.4 Performance Criteria

The following modelling, analysis and design criteria shall be submitted:

1- The analysis calculation document shall include reference to the dated structuresmanual. Tabulate loads and reactions and identify critical design values.

2- Reasonable 2-D analysis shall be permitted as an alternative method for initialestimating straining actions and reactions. Detailed higher level 3-D finite elementapproach must be applied.

3- The 3-D computer model with boundary & base restraint conditions should reflectthe actual geometry and performance of structure.


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4- For medium and long span continuous bridges of special importance, the effectsof vertical ground excitation and seismic wave propagation should be furtherinvestigated.

5- Fatigue load frequency shall be based on traffic study report.6- Special attention should be given to the dynamic magnification due to

superstructure flexibility result.7- Soil parameters used in sub-structure and seismic analysis shall be as

recommended in the geotechnical investigation report.8- Lateral soil-pile-cape interaction must be determined considering sub-grade

coefficients approved by the geotechnical and hydrogeological Engineers.9- The design shall be carried out the stressing sequence, prestressing and

construction stages effects. Method of supporting, assembly and erection shouldbe studied. All construction constrains and construction load assumptions shall bespecified on the drawings.

10-All connections should be standardized as much as possible.11-The eccentricity between the section centroid and shear center shall be evaluated

during the construction phase.12-The transverse and interface shear design for large skewed structures should be

evaluated carefully.13-The type, position, method and design of lifting should be suggested.14-Analyze the stability and lateral buckling of girders for wind loading and

handling/erection during construction and prior to pouring the deck slab.15-Initial prestress, effective force, elongation and prestress losses shall be shown on

the drawings. Prestress force and elongations shall be checked and recordedduring the stressing operations.

16-Pile foundations shall be designed with a minimum safety factor of 3 4.17-For un-improved soils, pile foundations shall be designed to account for negative

skin friction plus lateral spreading of the fill material. Both shallow and deepfoundations should be designed for aggressive ground conditions (refer to soilinvesting. & piling design guidelines for details).

18-Static and dynamic pile testing for main and trial piles should be confirming withspecification requirements. Specify at least one boring at each pier.

22.5 Software

The popular commercial structural analysis software packages called SAP2000; STAAD-Pro & PROKON are commonly used tools and accepted by CED. Proper computersoftware not listed above shall be submitted for review and approval prior to adopting inthe analysis and design.

22.6 Unit System

All structural calculations, computer reports, specialist consultant recommendations anddrawings shall be presented in SI metric unit system.


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22.7 Pre-Stressing System and Material

Prestressed concrete has been a favoured material and popular choice for medium andlong span bridge structures, providing design flexibility and rapid construction. In order

to maintain acceptable durability level within required design life span, Epoxy CoatedPrestressing Strands can be adopted. The following parameters shall be considered andsubmitted:

1- All material components used in any construction shall be of a type and qualitythat confirms the purpose for which they are used.

2- Prestressing system provider shall submit an undertaking letter through thespecialist to CED that contains conformation of full compatibility between hissystem components, tensioning equipments and strands used in job site.

3- Stressing force at final jacking stage shall not be less than 45% of tendon breakingload; otherwise, the specialist shall submit method statement for special

procedures which has to be carried out for CED approval.4- The type of strand permitted for use shall be filled epoxy-coated seven- wire

strands.5- Implementation of epoxy coated strands shall generally conform to PCI

Committee report titled Guidelines for the Use of Epoxy-Coated Strand forinternal and external pre-stressing.

6- The minimum accepted coating thickness after curing shall be 0.38mm7- Value of stress relaxation loss shall be reported to CED by the specialist and

obtained by the manufacturer, the specialist shall be held responsible for theaccuracy of the reported value.

8- Practical value for seating loss shall be obtained from the manufacturer of epoxy

coated strand and reported to CED; in absence of such information, seating losscan be considered as 9mm for guidance.

9- PTI Guide Specifications titled Recommendations for Stay Cable Design, Testingand Installation" shall be generally considered as the Guidelines for Use of EpoxyCoated Strands for Stay Cable Bridges.

10-Polyethylene duct shall be used for internal pre stressing; the inner diameter ofduct shall be consulted with the manufacturer and reported by the specialist.

11-Testing Certificates as reported in ASTM A882/A882M-o4A, and/or ISO 14655shall be obtained from the manufacturer and submitted by Pre-Stressing Specialistfor CED review prior to starting of installation on site.


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23.0 NOCs required after obtaining the Bridge Building Permit:

23.1 Submission requirements for the pre-stressing specialist approval upon receivingthe bridge permit

- Copy of the local professional license.

- Detailed company profile.

- The Approved per-stressing system.

- Curriculum vitae for the project engineer, and site supervisor.

- Material submission inclusive of material sources.

- Material test certificates as mentioned in Clause 7 for the strands and additionaltesting for the pre-stressing system mainly:

- Fatigue Test- Efficiency Test

- Static Load Test

23.2 Submission requirements for Bearing approval upon receiving the bridge permit

- Manufacturer company profile.

- Material submission inclusive of material sources

- Detailed bearing design with prior consultant approval

- Full scale testing report from one of CED approved laboratories

23.3 Submission requirements for Expansion Joint approval upon receiving the bridgepermit

- Manufacturer company profile.

- Material submission inclusive of material sources

- Full scale testing report from one of CED approved laboratories