E_div-6-Subbase and Aggregate Bases

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DIVISION 6 SUBBASE AND AGGREGATE BASES 181

6.1 Description 181

6.2 Production And Storage Of Aggregate Materials 181

6.2.1 Description 181

6.2.2 Material Sources 181

6.2.3 Aggregate Materials Production 181

6.2.3.1 Site Preparation 181

6.2.3.2 Machines And Equipments 181

6.2.3.3 Production Of Natural Aggregate 181

6.2.3.4 Production Of Crushed Aggregate 183

6.2.4 Aggregate Transportation 183

6.2.5 Aggregate Stockpiling 183

6.2.6 Surplus Waste Materials 184

6.2.7 Site Clearing 184

6.2.8 Acceptance 184 6.2.9 Measuring And Payment 185

6.3 Aggregate Subbase 185


6.3.2 Materials 185

6.3.3 Design Job Mix Formula 186

6.3.4 Equipments 187

6.3.5 Experimental Section 188

6.3.6 Construction 188

6.3.7 Protection Of Constructed Layers 190

6.3.8 Finishing Requirements 190

6.3.9 Acceptance 190 6.3.10 Measurements 191

6.3.11 Payment 191

6.4 Aggregate Bases 195


6.4.2 Materials 195



6.4.5 Experimental Section 196

6.4.6 Construction 196

6.4.6.1 Surfaces Preparation 1966.4.6.2 Mixing And Transportation 197

6.4.6.3 Spreading And Compaction 197

6.4.7 Maintaining The Constructed Layers 199


6.4.9 Acceptance 199

6.4.10 Measurements 200

6.4.11 Payment 200

6.5 Cement Treated Base 202


6.5.2 Materials 202

6.5.2.1 Cement 2026.5.2.2 Aggregate 202

EXIT



6.5.2.3 Water 202

6.5.2.4 Admixtures 202

6.5.2.5 Asphalt Curing Membrane 202



6.5.5 Construction 2056.5.5.1 Surface Preparation 205

6.5.5.2 Weather Limitations 205

6.5.5.3 Mixing 206

6.5.5.4 Compaction And Finishing 209

6.5.5.5 Construction Of Joints 210

6.5.5.6 Curing 210

6.5.6 Traffic Control 211


6.5.8 Acceptance 211


6.5.10 Payment 213

6.6 Emulsified Asphalt Treated Base 214

6.6.1 Work Description 214

6.6.2 Materials 214

6.6.3 Emulsified Asphalt Treated Base Mix 215

6.6.3.1 Job Mix Formula 215

6.6.3.2 Job Mix Formula Acceptance Procedures 215


6.6.5 Weather Limitations 216

6.6.6 Constructions 216

6.6.6.1 Emulsified Asphalt Material Preparation 2166.6.6.2 Aggregate Preparation 217

6.6.6.3 Central Mixing 217

6.6.6.4 Road Mixing 217

6.6.6.5 Spreading And Compaction 217

6.6.6.6 Finishing 218

6.6.7 Traffic Control 219

6.6.8 Work Acceptance 219

6.6.8.1 Quality Control 219

6.6.8.2 Quality Assurance 219


6.6.10 Payment 221

EXIT



General Specifications of Urban Roads Construction Division 6- Subbase and Aggergate Base

Ministry of Municipal & Rural Affairs – Kingdom of Saudi Arabia 181

DIVISION 6

SUBBASE AND AGGREGATE BASES

6.1 Description:This Division includes materials and execution methods required for the

construction of Subbases and aggregate Base courses, which includes:

-

Production and storage of aggregate materials.

- Aggregate Subbase.

- un-treated aggregate base.

- Cement treated aggregate base.

-

Asphalt treated aggregate base.

6.2 Production and storage of aggregate materials:

6.2.1 Description:This section includes production methods, transportation and stockpiling of

natural, crushed, or screened materials used in construction of roads and relevant

structures. Contractor shall provide the aggregate conform to the quality and gradation

requirements indicated in the special specifications, drawings, contract documents or

these general specifications.

6.2.2 Material Sources:

Unless otherwise the material sources are shown on the drawings or in the

special specifications, the contractor should specify those sources whether they are new

queries or authorized existing crushers.

Contractor, in cases, prior starting production or supplying the aggregate

materials by a period not less than 30 days, shall submit to the Engineer a technical

report, which includes:

1. Source (s).

2.

Types and approximate quantities of available rocks and materials.

3. The results of test on representative samples according to the type of work on

which these material proposed to be used, according to the requirement

indicated in the relevant divisions and sections of these general specifications or

special specifications.

4.

Machines, equipments and methods of crushing, screening and transporting of

rocks.5. Sites and methods of aggregate stockpiles.

6. The written agreement from the related agency and property owner for the new

suggested locations of material production and stockpiling.

Contractor is not allowed to start the production of aggregate materials before

the approval of the Engineer for the source. This approval is considered preliminary.

The final approval shall be made based on the test results for the materials actually

supplied to the project.

The contractor shall enable the Engineer to reach sites of the works, inspect

equipments, production and storing methods at any time during the construction. TheContractor shall obtain a new approval for the source as mentioned above whenever the

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source or production methods were changed or when the Engineer notices a significant

change in the supplied materials properties.

When contract documents contain information about the available sources and

specifications of materials, this information are considered as guides and does not

release the Contractor from the responsibility for providing materials conforming to thespecifications. The Contractor shall make his own studies to estimate the construction's

prices, regardless of the source and available materials. The Engineer has the right,

according to test results, to reject materials and to require from the Contractor to change

the source(s) if the materials were not technically acceptable the Contractor has no right

to claim any additional costs resulting from this.

6.2.3 Aggregate materials production:

This work shall consists of site preparation, provision of machines, equipments

and required arrangements for producing natural or crushed aggregate and screening of

the materials to the required sizes to obtain the required gradations, transportation,

storage of acceptable produced aggregate, disposal of extra materials and un-acceptablematerials at the approved sites. The produced aggregate shall achieve all the

requirements indicated for the specified works.

Contractor shall, at all work phases, follow the approved environmental

standards regarding to noise levels, air pollution and dust and he shall make all the

required arrangements to limit environmental pollution in all its forms.

6.2.3.1 Site Preparation:

Aggregate materials shall be produced at the approved sources according to item

(6.2.2) requirements of this section. Contractor, after the approval of the Engineer for

the source(s), shall remove overburden, waste and unsuitable materials covering the

aggregate or rock layers proposed to produce crushed aggregate, and transport all

removed and waste materials to sites approved by the Engineer. The removal and

clearing works are considered for charged only with other items and no payment for

them shall be made to the Contractor.

6.2.3.2 Machines and equipments:

Contractor shall provide all the machines and equipments required for the

production of crushed and natural aggregate according to the approved specifications

and it includes central or mobile crushers, suitable sieves sizes, belt conveyor,

excavation, loading, and transporting machines and all equipments needed for producing an aggregate conform to specifications of the required work item.

6.2.3.3 Production of Natural Aggregate:

Contractor shall produce natural aggregate conforming to the specification's of

the specified works in the sources approved by the Engineer.

The production operation shall include removal of all unsuitable materials including the

sizes larger than the maximum size required, and disposal of soil materials and other

undesirable materials using suitable methods including screening and/or washing.

Contractor shall prepare a work plan for disposal of unsuitable materials from

the material's source, separate aggregate materials into sizes and transport each sizeseparately to the stockpiles.

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6.2.3.4 Production of Crushed Aggregate: Crushed aggregate production shall be made from the approved sources

according to the types and specifications of the available rock materials, using the

crushing methods, which achieve the requirements for number of crushed faces and

shape of particle.

Contractor shall sieve the materials before crushing process through vibratory

sieves of suitable capacity to remove all the soil and rock materials of small sizes.

Contractor shall use the suitable crushers according to the rock types, select the

production capacity and calibrate the crusher to match the required gradations, screen

all the produced materials and apply a periodical inspection for blocked or wearied and

broken sieves.

The produced aggregate shall be separated into different sizes, which provide

the required gradation conform to the aggregate requirements according to the work

type.

Contractor on his expense shall wash the aggregate if indicated in the special

specifications or when the clay materials and dust exceed the allowable limits.

The production process shall be stopped when the crushing and screening

method does not fulfill aggregate specifications requirements. The contractor has no

right to commence aggregate production before the Engineer approval for the required

repair, modification procedures taken and verification of the produced aggregate

quality.

6.2.4 Aggregate Transportation:

Contractor shall load and transport aggregate from production centers or

stockpile by loaders and covered trucks using method which ensures no particle

segregation occurs or contamination of aggregate with soil or any deleterious materials.

It is not allowed to take aggregate from the 30 cm in contact with the ground from the

aggregate stockpile except when the storing floor is concrete. The aggregate shall be

taken from the bottom upwards to maintain the uniformity of aggregate gradation.

6.2.5 Aggregate Stockpiling:

Contractor shall transport and store the produced aggregate at the sites shown on

the drawings or other contract documents or sites approved by the Engineer. Contractorshall obtain a written agreement from the site owners for its use before starting of

aggregate transportation to these sites, Contractor shall clear and level those sites to a

leveled surfaces and provide water drainage facility at those sites.

Contractor shall store aggregate materials in separated stockpiles according to

sizes in distance apart or using concrete walls to avoid mixing of different sizes, and he

shall transport, discharge and store each size of aggregate in layers in such a way that

prevents particle segregation. The height of the stockpile shall not exceed 8 meters.

It is not allowed to use bulldozers or any other chain machines lead to breaking

or fracturing of aggregate during stockpiling process.

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Contractor is not allowed to use any areas within the urban for aggregate stockpiling

without a written approval from the concerned authorities.

Contractor shall follow the approved environmental standards at aggregate stockpiling

sites.

6.2.6 Surplus waste materials:Contractor shall immediately dispose of all clearance and waste materials or any

other unsuitable materials and transport them outside the production site to disposal

areas approved by the Engineer.

The Contractor shall store all the produced technically accepted surplus materials at the

stockpile sites indicated on the drawings, contract documents or specified by the

Engineer.

When the aggregate production is permitted, for certain contract works, the

ownership of aggregate surplus materials from particularly works related to specified

contract, is belong to Ministry and Contractor has no right to claim any additional costs

for this.

6.2.7 Site clearing:

Contractor when finishing the works in production and/or stockpile sites, shall

level, arrange and clean these sites from all wastes, debris, temporary structures, and

transport products and wastes to the approved sites.

6.2.8 Acceptance:

Contractor shall apply quality control for aggregate production by carrying out

all the required arrangements to ensure that the produced materials, production methods

achieving the quality requirements, indicated in the general specifications, and other

contract documents.

The Ministry shall apply the quality assurance works by verifying that the

contractor has carried out quality control procedures properly either through direct

supervision of the quality control procedures or by undertaking quality assurance

procedures neutrally on representative samples and with adequate numbers to judge the

execution and to decide in accepting or rejecting the completed work according to the

principles detailed in Division 17 of this general specifications except otherwise

specified in special specification or other contract documents.

1.

Quality control:Contractor shall apply quality control on materials and executed works and

monitor records and analyze results and draw quality charts for critical properties and

carry out all tests and measurements indicated in the relevant Divisions and Sections

according to type of works. Contractor shall submit to the Engineer copies from all tests

immediately and apply all the items indicated in sub-section 17.1.1 of these general

specifications

2. Quality Assurance:

Ministry at any time has the right to assure the quality of materials and executed

works through carrying out or ordering others under its direct supervision to test

materials and inspect production sites, equipments and methods of production.

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Ministry has the right to review contractor’s quality control records and compare

them statistically with quality assurance results to insure quality according to division

17 of these general specifications. And it has the right to inspect the contractor’s

laboratory and its equipments, its technical staff, methods of testing and construction to

insure the efficiency of the contractor’s technical staff and equipments and conformity

of investigation, testing and construction methods with the approved methods.

The Engineer has the right at anytime to stop the Contractor's production or

stockpiling process when he notices that suitable production or stockpiling conditions

according to specifications is not available, or when the contractor does not follow the

environmental protection standards, or when the produced materials do not achieve the

required specifications. The Engineer has the right to change the production source

when the available materials not conform to the specifications and the Contractor has no

right to claim any additional payments for this.

6.2.9 Measuring and Payment:

Measurement shall be made only for determining the produced and availablequantities but payment shall be done according to the work items in which aggregate

materials are used and the aggregate price shall be included in the prices of those items

unless otherwise indicated in the contract documents that payment shall be made for the

aggregate materials separately.

6.3 Aggregate Subbase:

6.3.1 Description:

This section includes material requirements and construction methods for the

aggregate Subbase includes supply, wetting, spreading, leveling and compaction of the

materials conformed to the approved technical specifications and finishing surfaces

according to the dimensions, levels and slopes shown on the drawings, special

specifications, contract documents and these general specifications.

6.3.2 Materials:

Contractor shall use, for the construction of Subbase layer, the aggregate that

conform to gradation and quality requirements indicated in the special specifications or

in this section.

The materials shall be capable of forming a durable and stable Subbase layer

after being wetted and compacted. The aggregate shall be solid water resistant materials

from natural sources or crushed rock, clean, free from impurities and friable materialssuch as organic materials, clay lumps, soluble salts and metals and it is not allowed to

use materials susceptible to disintegration when subjected to wetting or drying.

Aggregate shall fulfill the quality requirements specified in Table (6.3.1) unless

otherwise indicated in the special specifications. The blended aggregate shall achieve

one of the graded shown in Table (6.3.2) or any other gradation stipulated in the special

specifications within the variation allowed in the approved design job mix formula

indicated in Table (6.3.3).

When construction is made in areas with high or fluctuated water level or in

salty environment, the aggregate material types shall be suitable and water resistanthaving a soundness not exceeding 25 % according to AASHTO T-104 test by using

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sodium sulphate and their plasticity index shall not exceed 4 according to AASHTO T-

90 test. When the special specifications require using of open gradation aggregate, the

gradation indicated in the special specifications shall be used otherwise the gradation

No. 5 in Table (6.3.2) of this section shall be used.

Table 6.3.1: Quality requirements for Subbase layer aggregate

Property Test Designation Value

Los Angles Abrasion test % AASHTO T-96 50% (Maximum)

Soundness by Na SO4, 5 cycles AASHTO T-104 25% (Maximum)

Liquid limit%

Plasticity index %

AASHTO T-89

AASHTO T-90

25% (Maximum)

6 % (Maximum)

CBR % ASTM D-1883 50% (Minimum)

Table 6.3.2: Gradation Requirements for gravel Subbase layers

Percent Passing Sieves

GradationSieve size

(mm)(1) (2) (3) (4)

(5)

(open graded)

75 (3") 100 100

62.5 (2.5") 100 100

50 (2") 97-100 100 90-100 70-100

37.5 (1.5") 97-100 70-100 50-85

25 (1") 65-79 -

19 (

3

/4") 50-85 15-5512.5 (1/2") 45-59 -

9.5 (3/8")

6.3 (1/4") 0-20

4.75 (No. 4) 28-42 40-60 30-60 35-70 -

2.36 (No. 8) 0-10

0.425 (No. 40) 9-17

0.3 (No. 50) 0-8

0.075 (No. 2000 4-8 0-12 0-10 0-15 0-5

Table 6.3.3: Allowable variation in Aggregate Subbase Gradation

Sieve size, mm Tolerance limits

9.5 mm (3/8 inch) or larger ± 10 %

4.75 mm (No. 4) ± 7 %

0.075 mm (No. 200) ± 4 %

6.3.3 Design job mix formula:

1. Job mix requirements

The materials used shall achieve the quality requirements specified in Table

(6.3.1) unless otherwise indicated in special specifications, and the total gradation shallconform to the approved gradation in the special specifications or these general

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specifications or those approved by the Engineer within the tolerance limits indicated in

Table (6.3.3).

2. Job mix formula acceptance:

Contractor, prior starting of Subbase materials supply by a period not less than

30 days, shall submit to the Engineer a technical report of the design job mix formulaincluding:

1. Source(s) and gradation of the aggregate for each aggregate size or type and

blending percents of various sizes and the combined gradation.

2. Quality test results required in the special or general specifications for the

aggregate to be used in Subbase layer.

3. The method used for the production of each mix.

4.

Date of starting aggregate production of Subbase material.

The Engineer shall review the proposed job mix formula and if it does not contain

the required information, it shall be returned within 7 days to the Contractor to complete

the information and data required, and then resubmitted to the Engineer for approval.

If the job mix formula includes all the required information it shall be reviewed

within 14 days and accepted or rejected and returned to the Contractor to prepare and

submit a new job mix formula which fulfills the specified requirements and a new date

for starting production should be proposed.

When the test result and technical reports indicates that the proposed job mix

formula is conform to specification requirements, the Engineer shall issue a written

approval for it and the Contractor shall start the mix, production. It is not allowed to

start the aggregate production for Subbase mix before a written approval from the

Engineer for the job mix formula.

The Engineer approval for the design job mix formula does not release the

Contractor from responsibility for supplying materials conform to approved

specifications and construct Subbase according to drawings and contract documents or

these general specifications. The final approval shall be based on the test results of the

actually used materials.

The approved job mix formula is considered a basis for evaluating all materials

and constructed work in the subsequent phases of construction and the tolerance limits

of gradation shall be taken on the bases of same job mix formula.

Contractor has no right to make any modification in the approved job mix

formula unless a new job mix formula submitted and accepted according to

requirements indicated previously in this paragraph. The Contractor shall submit a new

job mix formula whenever the source of the materials actually supplied to the project or

production methods or materials properties and gradation is changed.

6.3.4 Equipments:

Contractor shall provide all the machines and equipments required for

collecting, mixing, screening, loading, transporting, spreading, leveling, wetting and

compacting the aggregate materials and finishing the Subbase according to the specialspecifications, drawings, contract documents and these general specifications. The

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machines and equipments shall be in good technical condition and in numbers and types

sufficient for constructing the work according to the work plan approved by the

Engineer. The contractor shall provide the required arrangements to lessen dust, noise

and pollution according to the environmental protection requirements.

The machines and equipments shall include, loading and hauling machines andequipments such as loaders and trucks, spreading, grading, compaction and leveling

machines such as graders and rollers and tankers provided with water distributors,

which can be calibrated. It is not allowed to use chain machines, sheep foot rollers, and

any other machines, which leads to fracturing or breaking of aggregate particles.

6.3.5 Experimental Section:

when special specifications indicates or the Engineer requires that, Contractor

prior to starting of construction, shall, construct an experimental section not less than

200 meters long for the purpose of verifying the efficiency of the machines, equipments,

possibility of construction according to approved specifications, to determine the

number of the required compaction passes, the quantity of water to be applied to reachthe suitable moisture content, and the thickness of the layer before and after

compaction.

Contractor shall modify the work plan or replace the machines and equipments

if the construction of Subbase layer not possible according to the Contractor's plan or

equipments. If the results of the experimental section are acceptable on the basis of the

test results then the construction method followed shall be approved, and Contractor has

not the right to make any modifications or replace machines or equipments without the

written approval from the Engineer.

6.3.6 Construction:

Prior to starting construction of Subbase, Contractor shall verify the completion,

finishing and handing over and approval of Subgrade layer by the Engineer and

according to the requirements of section 5.5. The Contractor shall verify that the

Subgrade was not damaged and when the period from Subgrade finishing and starting of

Subbase construction exceeds 15 days he shall verify the moisture content and

compaction degree and perform the required repair works when necessary. Contractor

shall not be paid any additional costs for this work.

Contractor shall remove all the loose materials, repair all the defects and adjust

levels of the parts not conforming with the final levels of Subgrade and achieve therequired cross slopes using method accepted by the Engineer for removing surplus

materials or adding new materials conforming to requirements of the Subbase while

adhering to construction requirements and compacting materials up to required degree

of compaction. Contractor has no right to claim any additional costs for repair works

and no right to start Subbase material supply and construction before obtaining the

written approval of the Engineer for the surfaces on which construction shall be made.

Contractor shall mix aggregate materials in central mixing plants and supply to

the site ready mix conforming to gradation requirements approved in the design job mix

formula. It is possible, if approved by the Engineer, to mix aggregate materials of

different sizes on special mixing pads or on site providing that the Contractor shall

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verify the possibility of obtaining a gradation conforming to required gradation without

any deleterious aggregate materials.

The Engineer has the right, when the required gradation not achieved or

Contractor fail to prevent mixing Subbase material with other unsuitable materials or

when mixing on the road causes damage to the previously constructed layers, to stop thework and require modifying and mixing method or providing of technically acceptable

materials from plants.

Materials shall be transported in wet or dry conditions by trucks having metal

boxes and discharged to the paver hopper or deposited on the surface considering that

the loading and unloading of the materials shall not cause segregation and the heaps

shall be distributed in distances that give a layer of required thickness before

compaction. The spreading of the heaps shall be made using graders, and it is not

allowed to use bulldozers. Spreading and leveling process shall continue until a layer

with uniform thickness and moisture content for the full depth is obtained with

approved cross fall.

Unless otherwise indicated in the special specifications, construction shall be in

layers suitable for the used compaction machines and equipments and the individual

layer thickness shall not be more than 20 cm. When the thickness of the Subbase layer

exceeds the maximum indicated thickness these layer shall be constructed in

approximately equal layers providing that the thickness of each layer does not exceed

20 cm.

Contractor before starting compaction shall verify the layer surface is smooth

with no depressions or pockets of extra moisture content or particle segregation, when

such distresses were noticed the required arrangements should be made for repairing,

using method accepted by the Engineer.

Layer compaction shall begin from the outer edge towards the road center line

while achieving the required overlapping between adjacent compaction passes, using

the machines and equipments suitable for the materials and layer thickness, the

compaction shall continue until the degree of not less than 100% of the maximum dry

density specified by AASHTO T-180 modified Proctor test at a uniform moisture

content not differ by more than 2% from the approved optimum moisture content.

Contractor shall provide the equipments capable of compacting areas whichcan't be compacted by normal rollers including manual operation equipments or

vibratory plate and shall change the thickness of compacted layers in these areas to suit

the used rollers so that uniform compaction degrees may be obtained for the full

constructed layer thickness and width.

The field density for each layer shall be determined by sand cone method

according to (AASHTO T-191) test or the nuclear method according to AASHTO T

310-01 or any other approved non-destructive test. The test shall be carried for the full

depth of the layer. The minimum number of readings when using nuclear or non-

destructive method at each location shall be not less than three (3) taken at each area in

different direction, and the average of these three readings is considered as the fielddensity of that location.

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For the purpose of determination of payment factor, the previous mentioned

required density values shall be reduces by 2% using statistical method.

Contractor shall level the final Subbase layer surface and spread materials so

that thickness before compaction shall be greater than the target thickness by

approximately 20-25% of the target thickness. The contractor shall continue levelingand removal process until achievements of the finishing requirements regarding

thickness, slopes and levels.

Each layer of the Subbase shall be measured at the beginning of construction

and during construction, the thickness measurements shall accepted when the final level

of the Subbase does not exceed tolerance limits of the levels indicated on the drawings

and in the contract documents, providing that the material requirements and compaction

degrees for the full depth of each layer is achieved.

The thickness used for determining payment factor shall be the specified

thickness minus 20 mm if the subsequent layer was aggregate and 10 mm if it wasasphalt or 90 % of the thickness shown on the drawings whichever is lesser.

6.3.7 Protection of Constructed layers:

Contractor shall maintain the constructed layers surface, free from any

deleterious or loose materials, and take the required arrangements to maintain moisture

content, compaction degree and water drainage until the subsequent layer is laid. When

the constructed layer is damaged for any reason, Contractor before subsequent layer

construction shall carry out the required repair works including re-pulverization,

spreading, wetting, compaction and finishing without any additional costs and the costs

shall be included on the other construction items.

6.3.8 Finishing requirements:

The Subbase layer shall be constructed according to the dimensions, slopes, and

thickness indicated on the drawings and special specifications.

The final surface levels of the Subbase shall not vary from the level shown on the

drawings or approved by the Engineer by more than 10 mm if the subsequent layer is of

asphalt or concrete or by not more than 20 mm if the subsequent layer is aggregate.

The final surface of Subbase shall be verified by taken cross sectional levels at

25 meters intervals providing that the number of the sections is not less than 5 in each

2000 square meters of the constructed layer. Measurement shall be done at each crosssection in 5 points at least.

The final surface smoothness shall be verified using straight edge 3 meters long

and the gap between the bottom surface of the straight edge and the surface between any

two contact points in any direction shall not exceed 10 mm when the subsequent layer is

aggregate or 6 mm when it is asphalt or concrete.

6.3.9 Acceptance:

Contractor shall control the quality of Subbase through performing all the

required measures to insure the used materials, methods of construction and the

completed works meet the quality requirements specified in these specifications andother contract documents.

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The Ministry has the right to ensure the quality by verifying Contractor's quality

control procedures either, through direct supervision of quality control activities or

performing quality assurance procedures neutrally, on a sufficient number of

representative samples to determine the level of construction and to accept or reject the

constructed work on detailed bases in division 17 of this specifications except otherwise

indicated in the special specifications and other contract documents.

1. Quality control:

Contractor shall control the quality of materials and constructed works, monitor,

record and analyze results, draw quality charts for critical properties and perform all

required tests and measurements in Table (6.3.4).

Contractor shall submit to the Engineer with copies of all the measurements, reports

tests results and he shall apply all the articles stated in item 17.1.1 of this specifications.

2.

Quality assurance:

The Ministry has the right to ensure the quality of materials and completed

works through carrying out or ordering others under its direct supervision to carry outthe necessary tests and measurements, and checking the completed work for each or

some of quality control items specified in Table (6.3.4).

Ministry has the right to review contractor’s quality control records and to

compare these records statistically with the results obtained by quality assurance as

specified in division 17 of these specifications, and inspect contractor’s equipments,

technical staff, and measurement and construction methods, to determine the degree of

compliance of measurements and constructed methods with the approved requirements.

Works shall be accepted with the prices specified in the contract or with lower

prices or might be rejected according to the quality levels by applying the statistical

method specified in division 17 of these specifications except otherwise specified by the


6.3.10 Measurements:

The Subbase layer shall be measured in cubic meters or as specified in the

special specifications, after being laid and compacted according to the specified

thickness and within the dimensions and levels shown on the drawings or according to

the Engineer's instructions.

6.3.11 Payment:

Payment shall be made for actually constructed and technically accepted works

within the approved limits, dimensions and prices indicated in the contract or reduced prices results from applying of quality assurance procedure.

The paid amounts are considered full compensation for the extraction, supply,

mixing, transporting, spreading, wetting, compacting of materials and finishing the

works, provision and operation of machines and equipments, labor, tests, measurements

benefits, revenues, fees, third party payments and all other requirements to construct the

works in accordance with the drawings, special and general specifications. Payment

shall be according to the item indicated in Table (6.3.5) without contradiction with

contract documents:

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Table 6.3.4: Quality Control Procedures for Subbase

Work Properties Test method

Location

of

Samples

Sampling frequency Requirements

gradation AASHTOT-(27)

Aggregate

quality

requirements

All

requirements

indicated in

Table 6.3.1

Raw

materials

Moisture -

Density

relationship

AASHTO

T-180

At source

3 tests on differentsamples from each source

and at source approval

and at design job mix

formula, or when source

is changed, or when

constructed works

properties is changed and

one test each month

Items 6.3.2,

6.3.3

Aggregate

gradation

AASHTO

T-27Item 6.3.3

Moisture/

Density

relationship

AASHTO

T-180Item 6.3.2Materials

during use

Aggregate

quality

requirements

Requirement

s indicated in

Table 6.3.1

3 tests at the starting of

material supply and onetest each 5000 cubic

meters of supplied

materials or when

constructed work

properties is changed.Table 6.3.1

Field density

AASHTO

T-191/

T -310-01

or any non-

destructivetest method

One test every day or for

every constructed 2000

square meters of each

layer

Item 6.3.6

One measurement every

day or for each 2000

square meters of the

constructed layer

Item 6.3.8Thickness

Field

measurements

Levels and

dimensions

Survey

measurement

Cross sectional levels at

25 m interval or 5 cross

sections each 2000

square meters whichever

the greater.

Item 6.3.8

Constructed

works

Surface

smoothnessStraight edge

At site

Five (5) measurementseach 2000 square meters

or between cross sections

indicated for levels

whichever greater.

Item 6.3.8

Table 6.3.5: Payment Items for subbase layer

Item No. Work type Unit

6.3.1 Subbase layer m3

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6.4 Aggregate Bases:

6.4.1 Description:

This section contains material requirements and constructed methods for the

construction of the un-treated aggregate Base according to the dimensions, levels,

thickness and slopes shown on the drawings and other contract documents.

6.4.2 Materials:

Contractor shall provide the aggregate materials conform to requirements of the

special specifications or these general specifications, these materials shall be crushed

coarse and fine aggregate or natural aggregate or furnace slag after being broken and

screened to achieve the required gradation and verify its density.

The materials used shall be clean, free from impurities, organic materials, friable

particles and clay lumps, and not more than 10% of thin and elongated particles. The

materials, after being spread, wetted and compacted, shall form a sound and stable base,

which complies with the special technical specifications or these general specifications.

The untreated aggregate Base shall achieve, unless otherwise indicated in thespecial specifications, the quality and gradation requirements indicated in Table (6.4.1)

and Table (6.4.2) considering the following:

1. Category (A) aggregate, type (1) gradation shall be used for arterial roads,

highways, industrial areas and heavy vehicles parking areas,

2.

Category (B) aggregate, gradation (2) shall be used for collective roads.

3. Category C aggregate, using gradation (3) shall be used for secondary roads at

residential areas.

When the specifications require using of open gradation aggregate it shall

conform to one of the gradations indicated in Table (6.4.3) and the quality of the

materials shall be from category (A) as shown in Table (6.4.1). Open gradation

materials shall be treated, when constructing main roads and streets, industrial area

roads and heavy vehicles parking areas, with cement or any other method stipulated in

the special specifications or the technical study.

Table 6.4.1: Quality Requirements for Aggregate Bases

Values according to

classificationQuality RequirementsTesting

MethodClass A Class B Class C

Soundness in sodium sulfate, five

cycles , maximum, %

AASHTO

T-10412 18 24

Los Angles Abrasion Test,

maximum, %

AASHTO

T-19640 45 50

Sand equivalent , minimum, %AASHTO

T-17645 35 25

Liquid limit, maximum, %AASHTO

T - 8925 25 25

Plasticity index ,maximum, %AASHTO

T-906 6 6

California Baring Ratio,

minimum, %

AASHTO

T-193100 80 65

Aggregate angularity two crushedfaces, minimum, %

ASTMD-5821

80 70 50

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Table 6.4.2: Gradation Requirements for Aggregate Bases

Percent passing by weightSieve Size, mm, (inch)

(1) (2) (3)

50 mm, (2 inches) 100 - -37.5 mm, (1.5 inch) 97-100 100 -

25 mm, (1 inch) 97-100 100

19 mm, (3/4 inch) 67-81 97-100

9.5 mm, (3/8 inch) 56-70 67-79

4.75 mm (No. 4) 33-47 39-53 47-59

0.425 mm (No. 40) 10-19 12-21 12-21

0.075 mm (No. 200) 4-8 4-8 4-8

Percent of material passing No. 200 sieve size (0.075 mm) shall not exceed half of

percent passing sieve No. 40 (0.425 mm)

Table 6.4.3: Open Graded Gradations

Sieve Size, mm, (sieve No.) Percent Passing by weight

75 (3 inch) 100

50 (2 inch) 100 70-100

37.5 (1.5 inch) 75-100 50-85

25 (1 inch) 100 - -

19 (3/4 inch) 75-100 35-65 15-55

9.5 (3/8 inch) 30-65 5-35 -6.3 (1/4 inch) - - 0-20

4.75 (No. 4) 5-30 0-15 -

2.36 (No. 8) 0-10 0-10 0-10

0.300 (No. 16) 0-8 0-8 0-8

0.075 (No. 200) 0-5 0-5 0-5

6.4.3 Design Job Mix Formula:

1. Job mix requirements:

Contractor shall select the aggregate material source(s) and perform the

preliminary tests to verify achievement of the specifications quality requirement, the

possibility of mixing to obtain the required gradations and the quantities available at

each source.

The Base materials, unless otherwise indicated in special specifications shall

achieve the quality requirements indicated in Table (6.4.1), and the combined gradation

shall conform to approved gradation in special specifications or these general

specifications or the gradation approved by the Engineer within the tolerance limits

indicated in Table (6.4.4).

2. Job mix formula acceptance procedures:

Prior to starting supply of the untreated Base materials by a period not less than30 days, Contractor shall submit to the Engineer a technical report including the job mix

formula for the aggregate materials conform to requirements indicated in the special

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specifications, contract documents or these general specifications. It should contain at

least the following:

1. Source(s) of materials.

2.

The aggregate gradations available at each source.

3. Gradations of different sizes in each stockpile.

4.

Percent and methods of mixing different sizes and the produced gradation thatconform to the approved gradations in the specifications.

5. Results of quality tests

6.

Expected date for starting mix production.

The Engineer shall study the report of design job mix formula proposed by

Contractor, if the report does not include all the required information the Engineer shall

return the report within 7 days and Contractor shall complete the information and

resubmit it to the Engineer. But if the information and data were complete, the Engineer

shall verify materials conformity to quality and gradation requirements and approve or

reject the job mix formula within 14 days.

If the proposed job formula does not fulfill the specifications, the Contractor

shall submit a new job mix formula. However, if it achieves the specifications the

Engineer shall issue written approval and Contractor has the right to start production of

the mix.

The Engineer's approval for design job mix formula is only preliminary and the

final acceptance for the materials is made based on test results of materials supplied to

the site. Contractor shall enable the Engineer to take samples and investigate production

sites throughout construction phases.

The design job formula approved by the Engineer is considered a basis for

comparing the supplied and used material properties. Moreover, Contractor shall follow

the job mix formula throughout the work period and the gradations of the materials

supplied to the site shall conform to the approved gradation in job mix formula within

the tolerance limits allowed as indicated in Table (6.4.4).

Contractor whenever the materials source, properties, or production method

changed or when the Engineer notices a significant change in supplied materials

specifications, shall submit a new or modified job mix formula reflects those changes

and he shall not continue material supply before obtaining the Engineer's approval for

the new job mix formula.

Table 6.4.4: Gradations Tolerance Limits

Sieve size (No), mm Tolerance limits

19 (3/4 inch) or more ± 6 percent

9.5 (3/8 inch) ± 6 percent

4.75 (No. 4) ± 6 percent

0.425 (No. 40) ± 4 percent

0.075 (NO. 200) ± 3 percent

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6.4.4 Equipments:

Contractor shall provide all machines and equipments required for producing the

aggregate materials and construct untreated Base according to drawings, special

specifications or these general specifications.

These machines and equipments shall be in the numbers, types, good technical

condition and capable to construct the works according to the approved time schedule.

The equipments shall include mixing, transporting, spreading, leveling, wetting

and compacting machines such as aggregate mixers, loaders, trucks, graders, spreaders,

adjustable water distributors and rollers, It is not allowed to use chain machines and

sheep foot rollers or any machines or equipments cause damage to the materials and

affect their properties and gradation.

6.4.5 Experimental Section:

Contractor, when special specifications or the Engineer requires that, shall

construct experimental section not less than 200 meters long, to verify his capability for

constructing aggregate Base conform to drawings, special specifications or thesegeneral specifications and to determine the water quantity required to be added, the

required compaction passes and thickness required before compaction, Using

construction method and available equipments.

When test results show that, the work plan and available machines and

equipments are capable to construct the required works, results are approved and

Contractor shall follow the approved construction method and has no right to make any

changes in machines or that method without a written approval from the Engineer.

However, if the results of the experimental section were not technically

acceptable, Contractor shall make the required modifications in the construction method

or machines to achieve the approved specifications.

6.4.6 Construction:

6.4.6.1 Surfaces preparation:

Prior Contractor start materials supply and construction of aggregate Base all

previous works shall be completed and handed over according to drawings, special

specifications and these general specifications. It is necessary to insure these layers have

not been subjected to any damages or loose or change in their compaction degree or

moisture content.

Contractor on his own expense shall remove all deleterious and loose materials

and repair all surfaces' defects and has no right to claim any additional costs for this

work.

When the period between the previous layer construction and the beginning of

Base construction exceeds two weeks the compaction degree and moisture content of

the constructed layer shall be verified by field density test, if the test results obtained

show a change in compaction degree, Contractor on his expense shall rewet and

compact that layer up to required compaction degree.

The Contractor is not allowed to start materials supply and aggregate Baseconstruction before receiving a written approval of the Engineer.

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The Subbase or Subgrade shall be wetted before placing the aggregate Base to ensure

layers bonding.

6.4.6.2 Mixing and Transportation:

Water and aggregate shall be fully mixed in calibrated plant mixer capable to

control feeding and mixing of different material sizes to provide mix conform toapproved gradation in the design job mix formula and it is not allowed to mix materials

on site.

Water shall be applied to the aggregate during mixing using calibrated

distributor to obtain a mix of uniform moisture content closed to optimum moisture

content determined by Modified Proctor Test, considering the percent of evaporation

during transportation and spreading.

The mixed aggregate shall be loaded and transported by covered trucks. The loading

and discharging process shall be performed in a method that prevents particles

segregation of materials.

6.4.6.3 Spreading and Compaction:

The aggregate Base shall be constructed in layers with thickness that suits the

materials used and the available compaction equipments on the basis of the

experimental section results and the thickness of each layer shall not exceed 20 cm.

The materials shall be supplied to the site in wet condition with moisture content

closed to optimum moisture content. The Base materials shall be spread using

mechanical spreader or shall be placed in distributed heaps on surface to provide, after

spreading a uniform layer conform to the approved thickness before compaction.

Consideration shall be made to avoid particle segregation during transportation, loading

and spreading. When these materials have been exposed to segregation, Contractor shall

remove all segregated materials and replace them with other acceptable materials.

Moreover, the additional grading can be done using motor grader.

The spread materials shall achieve the thickness, slope and approved cross

section, and the layer shall be leveled without depressions or particle segregated

materials or pockets in which water may collect.

Compaction shall be executed using approved work plan rollers and according to

experimental section results, those rollers shall be capable of compacting the layers forfull thickness up to required compaction degrees without leading to particle fracturing

or grinding.

The layer thickness before compaction indicated in Table (6.4.5) can be used

according to rollers, however, the approved thickness shall be determined based on test

section's results of field density and Engineer's comments during construction.

When total thickness of constructed Base is greater than thickness approved for

compaction according to available equipment, the construction shall be performed in

layers providing that the thickness of each layer shall not exceed the suitable thickness

for compaction.

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Table 6.4.5: Suitable Layer Thickness According to Roller Type

Roller type Layer thickness after compaction, cm

Vibratory, more than 12 tons 20

Vibratory, (10-12) Ton 15

Normal rollers 10

Contractor shall start compaction of each layer longitudinally, from the outer

side in the cross section to inner side with adequate overlapping distance between

adjacent passes, which shall be less than 15 cm.. Compaction shall continue up to

degree of not less than 100 % of the maximum dry density, determined by Modified

Proctor Test AASHTO T-180 for the same materials, at uniform moisture content not

differs by more than 2 % from optimum moisture content.

During compaction, Contractor shall compensate for water evaporation usingsuitable distributor allow regular and uniform spraying.

Contractor shall remove loose materials and carry the required remedies for

depressed and cavity areas existed in the Base layer surface, treat and re-compact these

sections as directed by the Engineer, to obtain stable layer capable to sustain the

subsequent layers. Contractor has no right to claim any additional cost for this work.

Prior starting construction of the subsequent layer the first layer shall be finished

and compacted to required degrees and handed over and sprayed with water to provide

the required bond between layers.

The compaction degree shall be determined using field density test as percent of

maximum dry density obtained from Proctor modified test for the used material and the

minimum compaction degree for determination of pay item using statistical procedure is

the above acceptable level minus 2 %. The field density test shall be done using sand

cone method according to AASHTO T-191 or nuclear method according to AASHTO

T-310-01or any other non-destructive testing method. The field density test shall be

performed for the full thickness of the layer. When using nuclear method or any non-

destructive test a minimum of three readings shall be taken at each location the average

of three readings should be the density of that location.

Base layer thickness shall be measured before construction and during

construction and the final level of the Base accepted if it does not exceed the tolerance

limits of levels shown on the drawings and contract documents, providing that the

materials requirements and compaction degrees for the full depth of each layer has been

achieved. The thickness shown on the drawings minus 10 mm shall be taken to

determine the quality index and payment factor.

The final Base layer shall be finished according to the dimensions, thickness and

slopes shown on the drawings, special specifications or these general specifications.

Consideration shall be given to spreading and leveling of the final layer materials and

the final levels can be verified using stakes or any other guiding method accepted by theEngineer. The materials shall be spread so that their thickness before compaction is

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greater than the specified thickness by approximately 20-25%. Leveling shall continue

until the final layer surface conformed to approved level and cross section.

6.4.7 Maintaining the constructed layers:

Contractor shall maintain the constructed layers free from any deleterious and

loose materials and perform all required procedures to maintain moisture content,compaction degree and drains until lying of the subsequent layer. When any damage is

occur in the constructed layer Contractor shall perform the required repair works

including re-plowing, spreading, wetting, compaction and finishing, before commences

construction of the next layers, and Contractor has no the right to claim any additional

cost for this work and the cost shall be included on other construction item.

6.4.8 Finishing requirements:

The Base shall be finished according to the dimensions, slopes and thickness

shown on the drawings and special specifications.

The final surface levels of the Base shall not differ from the level shown on the

drawings or approved from the Engineer by more than 10 mm if the next layer was anasphalt or concrete layer.

Verification of the levels shall be on basis of final measurements performed in at

least 5 points of each cross section taken in interval of 25 meters providing that the

number of the sections shall not be less than 5 for each 2000 square meter.

The surface of the final layer of Base shall be smooth and conform to slope and

level shown on the drawings or special specifications. The smoothness shall be

inspected using straight edge 3 meters long. The clearance between bottom of straight

edge and the surface of the layer in any direction between any two contact points shall

not exceed 6 mm.

6.4.9 Acceptance:

Contractor shall control the quality of aggregate Base through performing all the

required measurements to insure used materials, methods and the completed works meet

the quality requirements specified in these specifications and other contract documents.

The Ministry has a right to ensure the quality by verifying contractor's quality

control procedures either, through direct supervision or carrying out quality assurance

procedures, neutrally on a sufficient number of representative samples to determine the

level of construction, and to accept or reject constructed work on basis detailed in

division 17 of this specifications, except otherwise indicated in the specialspecifications and other contract documents.

1. Quality Control:

Contractor shall apply control the quality of materials and constructed works,

monitor record and analyze the results, draw the quality charts for critical properties and

perform all tests and measurements indicated in Table (6.4.6).

Contractor shall submit to the Engineer copies of all tests and apply all

requirements indicated in item 17.1.1 of these general specifications.


The Ministry has the right to ensure the quality of materials and completedworks through carrying out or ordering others under its direct supervision to carry out

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the necessary tests and measurements, and checking the completed work for each or

some quality control items specified in Table (6.4.6).


compare these records statistically with the results obtained by quality assurance as

specified in division 17 of these specifications, and inspect contractor’s equipments,technical staff, and measurement and construction methods, to determine the degree of

compliance of measurements and constructed methods with the approved requirements.



method specified in division 17 of this specifications except otherwise specified by the


6.4.10 Measurements:

The Base quantities shall be measured in cubic meters, unless otherwise indicate

special specifications and contract documents.

The measurements for payment shall include the actually constructed works

indicated on the drawings or contract documents, measurement shall not be done for

payment purposes for works constructed outside approved areas in drawings or

specified by the Engineer, and the quantities of these work items shall be calculated and

paid according to contract documents.

6.4.11 Payment:

Payment shall be made for actually executed and technically accepted work

quantities within the approved limits and dimensions according to contract rates or

reduced prices as a result of quality assurance works when contract documents call for

this.

The paid amounts are considered as full compensation for extraction,

transportation, spreading, wetting and compaction of the materials regardless of their

source, according to these general specifications, special specifications and other

contract documents. Plus provision, operation of machines, equipments and labor, tests,

measuring and all requirements to execute the works in accordance with drawings,

special and general specifications, benefits, revenues, fees and third party payments.

Payment shall be according to the item indicated in Table (6.4.7), withoutcontradicting the contract documents.

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Table 6.4.6: Quality Control for the Aggregate Base

Work Properties Test methodLocation of

SamplesSampling frequency Requirements

gradation

AASHTO

T-(27)

Aggregate

quality

requirements

All tests

indicated in

Table 6.4.1Raw

materials

Moisture

/Density

relationship

AASHTO T-

180

At source

3 tests on different

samples from eachsource for source

approval and design job

mix formula approval

or when source is

changed, or material

properties, or

constructed works is

changed, and a test

each month.

Items

6.4.2, 6.4.3

Aggregate

gradation

AASHTO

T-27, T-11

Items

6.4.3

Moisture

/Density

relationship

AASHTO

T-180

Items

6.4.2

Materials

during

using

Aggregate

quality

requirements

All

requirements

indicated in

Table 6.3.1

3 tests at starting ofmaterial supply, and

one test every 5000 m3

of supplied materials or

when properties of

constructed works is

changed or one test

each week. Items

6.4.3

Field density

AASHTO -191

AASHTO

T-310-01or any other

non-destructive

test

One test each day or for

each 2000 m2 of eachconstructed layer.

Items6.3.6

thicknessField

measurements

One measurement each

day or for each 2000 m2

of the executed layer.

Items

6.4.6

Dimensions and

levels

Survey

measurements

One cross section each

25 meters or 5 cross

sections each 2000 m2

whichever greater.

Items

6.4.7

Works

Surface

SmoothnessStraight edge

At site

5 measurements each2000 m2 or

measurements between

approved cross sections

for level's measurement

whichever greater.

Items

6.4.7

Table 6.4.7 Payment Item for Aggregate base

Item No. Payment item Payment unit

6.4.1 Aggregate Base m3

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6.5 Cement Treated Base:

6.5.1 Description:

This section consists of materials requirements and construction methods for

execution of cement treated aggregate Base. The work includes material provision, mix

production, transportation, spreading on prepared surfaces, compaction and finishing

according to approved thickness, slope, levels and cross section indicated in drawings,special specifications and these general specifications.

6.5.2 Materials:

6.5.2.1 Cement:

The cement used shall conform to types indicated in special specifications; it should

be suitable to local environment conditions and fulfill the requirements of the standard

specifications indicated hereafter:

1. Sulfate resistant Portland cement shall achieve requirements of (ASTM C 150).

2. Blended cement shall achieve requirements of (ASTM C 595) for Pozolana

cement type IP or (ASTM C 1157) for modified Pozolana cement type I (PM).

6.5.2.2 Aggregate:

Cement-treated materials shall achieve gradation requirements indicated in

Table (6.5.1) or any other gradation indicated in special specifications or approved by

testing that it can achieve design requirements. The aggregate shall achieve quality

requirements indicated in Table (6.5.2), unless otherwise indicated in the special

specifications.

6.5.2.3 Water:

Water used in concrete mixing and curing shall be clear and free from harmful

materials, which caused hardening of cement mixture such as oils, alkaline, plant,

organic materials and salt. Water shall not contain of more than 1000 unit per million of

chloride (CL2- -) or 3000 per million of sulphates (SO4

+ +), when the specifications or

the Engineer require water shall be tested according to (AASHTO T-26) test.

6.5.2.4 Admixtures:

When the special specifications require using of some admixtures such as fly ash

or retarding admixtures these materials shall be applied, using method and percent

specified in special specifications and they shall be supplied from approved sources

according to a source certificate. The fly ash shall conform to AASHTO M 295

specifications, and the setting retarding admixtures shall fulfill the requirements of

specification AASHTO M 194.

6.5.2.5 Asphalt Curing Membrane:

When special specifications indicate construction of asphalt curing membrane

the used material shall be emulsified asphalt type (SS-1h or CSS-1h) and achieve the

requirements indicated in division 7 of these general specifications.

6.5.3 Design job mix formula:

1. Requirements of design job mix:

The mix shall achieve all quality requirements indicated in the special

specifications and other contract documents.

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Table 6.5.1: Aggregate Gradations

Percent passing by weight %Sieve Size

(mm) Gradation 1 Gradation 2 Gradation 3 Gradation 4

50 (2 inch) 100

37.5 (1.5 inch) 100

25 (1 inch) 90-100 100

19 (3/4 inch) 60-95 100 80-100

9.5 (3/8 inch) 50-100

4.75 (4) 15-75 50-100 35-70

2.36 (8) 35-55

1.18 (16) 15-35

0.425 (40) 10-35 15-60

0.300 (50) 5-20

0.150 (100) 5-15 5-30

0.075 (200) 0-5 0-10 0-8 0-5

Table 6.5.2: Aggregate quality requirements

Index Test Designation Limits

Los Angles Abrasion Test, 500 cycle AASHTO T-96 50 %maximum

Sodium Sulphate Soundness, 5 cycles AASHTO T-104 12 % maximum

Durability index of fine and coarse

aggregateAASHTO T-210 35 minimum

Aggregate angularity ASTM D 5821 50 % minimum

Liquid limit AASHTO T-89 25 % maximumPlasticity index AASHTO T-90 6 % maximum

Organic materials AASHTO T-21 2 % maximum

Sulphates % AASHTO T-290 1 % maximum

Unless otherwise indicated in special specifications, the average of five soaked

samples unconfined compressive strength of the cement treated Base shall not be less

than 50 kg/cm2 and no individual sample shall have unconfined compressive strength

less than 40 kg/cm2 after 7 days. The approved cement content not less than 4% by total

weight of mix when tested according to AASHTO T-(134, 126, 22) tests.

2. Job Mix Formula Acceptance:Prior starting construction of cement treated Base by 30 days, Contractor shall

submit to the Engineer a full technical report prepared by a specialized and qualified

agency including the design job mix formula. The report shall based on results of

laboratory tests of aggregate, cement, water and admixtures proposed for use in

producing the cement treated Base and shall contain the following information:

1. Source(s) of each material used to produce cement treated mix.

2. Source and type of cement and additives proposed attached with an approved

source certificate.

3. Quality test results of aggregate properties.

4.

Gradation of aggregate sizes at all stockpiles.

5.

Combined aggregate gradation and proportional percents of different sizes of

aggregate in the mix.

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6. Cement content in the mix, and water-cement ratio.

7. Mixture density at the proposed water-cement ratio on basis of (AASHTO T-

134) test method.

8.

Quality properties of the mixture such as unconfined compressive strength and

any other quality properties indicated in the special specifications.

9.

Results of all tests show materials conformity and mixture to requirements ofspecial specifications or these general specifications.

10. Type and percent of admixtures and additives in mixture on the basis of cement

dry weight and method of application and mixing.

11. Method of production, construction and curing of cement- treated Base.

The Engineer shall review the report of design job mix formula proposed by

Contractor, if not all required information is complete the Engineer shall return the

report within 7 days and Contractor shall complete the information and resubmit it to

the Engineer. If the information and data were complete, the Engineer shall verify

materials conformity to quality and gradation requirements and approve or reject the job

mix formula within 14 days from the date of its submission.

Contractor shall provide the adequate quantities of aggregate and all the mix

components and verify the availability of suitable water in adequate quantities for

production and wetting before starting production. It is not allowed for the Contractor to

change the sources and specifications of the materials used in preparing design job mix

formula without submitting a new design job mix formula approved by the Engineers.

The approval of design job formula by the Engineer shall be considered only

preliminary. The mix production and construction shall be verified to achieve the

requirements indicated in these specifications or special specifications based on tests

results of constructed experimental section, production quality control, and tests results

of field samples taken from the site during the first working day and quality control

procedure. When the Engineer notice significant in material or mix properties or in

constructed works shall require from contractor to stop the work and to take the

required arrangements to remove unsuitable materials and works and reconstruct these

works according to these general specifications, special specifications and Engineer's

instructions. Contractor shall be responsible for all the costs results from this and has no

right to claim any additional costs.

6.5.4 Equipments:

Prior to start construction, Contractor shall submit a list of proposed equipmentsfor cement-treated Base construction. These equipments shall be in good technical

condition, and in numbers, types conform to work plan requirements and time schedule

submitted by the Contractor, accepted by the Engineer, and capable of constructing and

finishing cement treated Base according to the drawings, special specifications and


Equipments shall include central plant or mobile mixers, trucks, pavers, graders,

rollers and cement distributors, water distributor, asphalt distributor and all

requirements for constructing the work according to the specifications. Types and

numbers shall be selected according to the approved work plan, mix method and time

schedule.

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6.5.5 Construction:

6.5.5.1 Surface preparation:

Before starting construction of cement treated Base, all previous works shall be

completed, tested and handed over. The surfaces on which cement treated aggregate

Base will be constructed shall be free from deleterious and loose materials, level,durable to receive cement treated base and capable to sustain traffic movement of

construction equipments and machines without causing any deformations.

Contractor should carry out all required works and arrangements to repair all

defects and surfaces deformations for the layer that receive cement treated Base. The

surface repair shall include removing deleterious, loose and waste materials, and

adjusting layer's levels. The layer's level shall be adjusted by removing of waste

materials, or adding new materials having same quality of repaired layer, and spreading,

leveling and compacting them according to the requirements of that layer, or by, re-

wetting and compacting the layer providing that the final surface shall achieve the

thickness, compaction, leveling and slope requirements indicated on the drawings or thespecial specifications or these general specifications and according to the Engineer's

instructions. Contractor has no right to claim any additional costs for this work.

Contractor not allowed to starts material supply or spread the cement treated

Base before the approval from the Engineer's for surface preparation works.

Prior to start spreading of the cement treated base, Contractor shall uniformly wetting

the previous layer's surface without excessive water causing log or week areas unable to

sustain movement of spreading and compaction equipments or lead to an increase of

moisture content to limits which do not allow a uniform mixing of materials with

cement when use on road mixing.

6.5.5.2 Weather Limitations:

Contractor shall not construct cement treated Base during bad weather

conditions which tend to increase water evaporation or change cement ratio in the mix

or affect mix properties or cement hardening and limiting the gained strength required.

Cement treated aggregate Base shall not be spread when temperature is less than

5 c°, or expected to reach this degree in the next day of spreading and compaction, or

when temperature is higher than 35 c°. It is possible according to a written approval

from the Engineer to ignore the above weather limitations limits if Contractor takes the

required precautions to maintain the mix and constructed works to decrease waterevaporation and cooling of the mix or its components without affecting the quality of

the treated base or its efficiency after construction. Contractor shall be responsible for

any results caused from this works, and he shall carry out on his expense all repair

works when necessary including re-construction of all sections conforming to

specifications. It is not allowed to construct cement treated Base during rainfall or dust

storms or when wind speed exceeds 25 km/hr or when wind speed may leads to cement

scattering during road mixing. The Contractor shall be responsible for maintaining the

surface on which the treated layer shall be laid in a technically acceptable condition

during all weather conditions, and dispose all materials or mix or works performed in

unsuitable weather conditions without having the right to claim any additional costs for

this work.

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6.5.5.3 Mixing: Cement, water, and admixtures indicated in the special specifications and design

job mix formula shall be applied according to approved percent and mixed until a

consistent mix were achieved for whole areas and thickness of treated layers. Unless

otherwise indicated in special specifications, the cement treated Base mix shall be

produced in central mixing plants.

When constructing small size works or approved from Ministry mixing may be

performed on road using mobile mixers if the Contractor proves that the produced mix

conform to required specifications and approved work plan. When approved by the

Engineer, the cement treated Base material may be mixed on the road surface using

motor grader for limited quantities when necessary and for not more than 50 linear

meters.

Contractor is fully responsible for producing a mix conforming to specifications

and design job mix formula regardless of the applied mixing method.

1. Mixing in Central Plant:

The cement treated Base mixes shall be produced in Batch plants mixers or

continuous mixers.

The mixers used shall be capable of producing uniform mix conforming to

requirements indicated in technical specifications and approved design job mix formula.

Mixers shall be calibrated and provided with all required control devices for feeding

aggregate according to approved gradation and feeding cement within tolerance limits

not exceed 5% and feeding water within tolerance limits not exceed 2% of the accepted

percentages in the approved design job mix formula.

Contractor shall submit with the design job formula a list shows type and site of

the plant proposed to use. Contractor not allowed starting mix production before the

Engineer's approval for the plant used. The produced mix shall be verified whether

conforming to specifications based on the first day production. When the produced mix

does not achieve the specified requirements, the production shall be stopped and the

required precautions shall be taken to calibrate the mixer or modify the design job mix

formula.

Contractor shall set out a plan to transport the mix according to a time schedule

for production and transportation, in which the time period from applying water toaggregate-cement mixture, spreading and starting of compaction shall be within the

allowed periods. The period from water application to starting of compaction shall not

exceed 30 minutes, unless otherwise allowed in the special specifications. The mix shall

be transported in specialized transportation equipments. The mix shall be discharged

from the plant to the trucks, transported and deposited in to spreader, without any

particles segregation, and all required arrangements shall be taken to lessen the loss in

moisture content.

The mix shall be spread using mechanical spreader or special spreading boxes

and if available space was not adequate for using one of above mentioned methods it is

possible, when necessary, to spread the mix using motor grader. Spreading, regardlessof the used method, shall be executed with required compacted thickness of the layer

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within the allowed variation and in one pass of spreading machine. The produced

surfaces shall be uniform, level, free from particles segregation and conform to the

slopes and cross sections shown on the drawings or in the specifications within the

allowed variation limits.

When the mix allowed to be spread on more than one lane simultaneously, the period between spreading the mix on the constructed lane and staring of spreading on

the adjacent lane shall not exceed 30 minutes, otherwise construction joints shall be

constructed.

2. On site mixing:

Road mix construction method by mobile or traveling mixers can be used after a

written approval from the Ministry, while mixing and spreading by motor grader shall

only used after a written approval from the Engineer for construction of limited

quantities of cement treated Base and for a distance not more than 50 meters. When

using any of the on site mixing methods, Contractor shall, on basis of practical

experimental results, prove that the test results of mix are uniform, achieve allrequirements and do not differ from design strength of the mix by more than 20%.

- Mixing by Mobile Mixers:

Mixing may be done on site by mobile mixers when the available areas were

enough for the operation of such mixers. These mixers shall be capable of producing a

mix conformed to approved specifications and shall be equipped with control systems

for cement and water application. The supplied aggregate materials shall conform to

approved gradation and quality requirements, when discharged in to the mixer, whereas

cement shall be applied in dry state, with the approved rate, and mixing it with

aggregate materials until a uniform mix is obtained, then water is applied with the

specified percent and the mixing shall continue until the final mix conformed to

specifications. The mix shall be transported to the construction site using approved

means of transportation and discharged in the spreader or spreading box then spread

according to the specified thickness, slope and cross section, compacted and finished.

- Mixing by Traveling Mixers:

When mixing on road by traveling mixers these mixers shall be capable of

picking all spread materials to be treated over the road, without contamination with any

other surface materials or deleterious materials. These mixers shall be capable of

applying cement within tolerance limits, and not more than 5 % of the specified rate in

the design job mix formula, then mixing it uniformly with the treated material andapplying water within variation limits not more than 2 % of the specified percent in the

design job mix formula.

Cement treated Base materials shall be spread on the prepared and approved

surface and leveled to thickness conformed to the approved technical specifications.

Transportation and spreading of aggregate materials shall be performed without causing

particles segregation or aggregate fracturing, according to slopes, cross sections and

thickness shown on the drawings or specifications and approved work plan.

The spread materials shall be wetted before applying cement by one day, and the

period between wettings and applying cement shall not be less than 12 hours. The

spreading process shall not lead to formation of weak areas or areas with excessive

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moisture content or formation of cement lumps some extend that may restrict the

uniformity of cement and aggregate mixing for full depth.

It is possible to apply cement in one batch or many batches, without formation

of cement lumps, and mixing continuously until a uniform mix in color and gradation

were obtained, at the specified cement rate before water application. Immediately aftercompletion of aggregate and cement mixing, water shall be applied in specified rate and

mixing shall continue until uniform moisture content is obtained for the whole mix.

- On surface mixing:

When special specifications allow that or when constructed limited quantities of

works, it is possible to distribute the cement over spread materials surface using a

distributor machine capable of applying cement uniformly on the material surface

within tolerance limits, and not more than 5% of the specified rate. The distributor

openings shall be as near as possible to the treated surface and covered from all sides to

prevent cement scattering. Spreading of cement also, can be performed by distribution

of bags on surface in forms of rows at calculated intervals, then the bags shall be openedand the cement distributed in the transverse directions. Finally, distribution process shall

be completed using equipments accepted by the Engineer, so that a uniform cement rate

is obtained for the whole area and thickness of the layer to be treated. The materials on

which cement is distributed shall be dry.

After cement is distributed, it shall be mixed in dry state with the aggregate

materials using plowing, pulverizing and mixing equipments, equipped with plowing

and pulverizing arms, teeth and rotating screw plows capable of pulverizing the

materials all over the layer and treated area and mixing the materials properly with

cement until a uniform mix is obtained in one pass. Then water shall be applied in

specified rates and plowing and pulverizing shall be repeated until a uniform mixture is

obtained according to the required cement rate and moisture content for the whole depth

of constructed layer materials shall be spread according to approved slopes, levels and

smoothness.

When constructing limited quantities of works it is possible, with approval of the

Engineer, to use automatic steering grader capable of pulverizing, uniformly mixing and

spreading materials according to the slopes, thickness and smoothness shown on the

drawings or in the special specifications or these general specifications. Motor grader

mixing shall not lead to materials contamination with Subgrade or Subbase materials or

any deleterious materials during mixing and spreading. The produced mix shall conformto approved design job mix formula. Cement shall be applied in a dry state pulverized

and consciously mixed with aggregate for the full depth of the constructed layer, until a

uniform color and gradation of the mix is obtained at the specified cement rate. Water

shall be applied, pulverized and mixed until a according to specified moisture content,

then the mixture is spread in one pass according to thickness, slopes and smoothness

shown on the drawings or special specifications.

Levels and thickness of spread layers shall be controlled using fixed stakes that

allows construction according to approved slopes and levels.

The period between cement and water application and starting of compaction shall not

exceed 30 minutes and all compaction and finishing processes shall be completedduring a period not more than 2.5 hours from cement and water applications.

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6.5.5.4 Compaction and Finishing: Compaction operations shall be started immediately after finishing of spreading

using smooth steel rollers of suitable weight ranged from 6-10 tons, or vibratory rollers

after disconnecting vibration system, these rollers shall be capable of compacting the

cement treated aggregate Base to compaction degree not less than 98% of the density

determined by AASHTO T-134 test for the full depth. Compaction shall not lead to breaking aggregate particles. The period between spreading completions and starting of

compaction shall not exceed 30 minutes considering the prevailing air temperature,

while the period between water application to aggregate-cement mixture and

completion of compaction shall not exceed 2.5 hours.

Contractor shall take all the necessary measures for eliminating formation of

random cracks through controlling the cement rate used, such that it does not exceed the

approved minimum limit in the design job mix formula and water ratio control. Also,

carrying out the works at the suitable climatic conditions when temperatures are getting

lower as far as possible and taking the required arrangements for construction in hot

weather and care about mostening throughout the curing period. When some randomcracks appear, he should carry out the required repair works according to the engineer's

instructions and filling cracks with the suitable materials. Except otherwise stipulated in

the special specifications for a specific type, filler materials shall comply with ASTM D

(3405, 3406). Also, he shall remove all parts in which cracks of more than 3 mm wide

cracks appear when the cracked area exceeds 15% of any 30 m2 area and to replace it

with another area technically accepted. As an alternative to removal and replacement,

contractor, according to a technical report prepared by a specialized agency and with the

acceptance of the engineer, may construct an asphalt layer absorbing to stresses.

Contractor has no right to claim any additional cost for that.

Compaction degree shall be determined for each constructed layer by taking

random samples at time interval immediately after completing compaction using sand

cone method, AASHTO T-191 test or the rubber balloon method according to

AASHTO T-205 test or nuclear method according to AASHTO T-310 or any other

approved nondestructive test method. When using nuclear method or any non-

destructive test a minimum of three readings shall be taken at each location and the

average of three readings should be the density of that location.

Compaction degree shall be calculated by dividing field density with maximum

dry density determined from AASHTO T-134 test.

The minimum limit of accepted compaction degree for determining the payment

factor using statistical method shall be the indicated degree in the beginning of this

paragraph minus 2%.

The unconfined compressive strength shall be determined by taking samples at

random time intervals from the mix, preparing, maintaining and testing them according

to AASHTO T-(134, 126, 22).The minimum allowed limit for calculating the payment

factor is 80% of the value obtained in the design job mix or the minimum strength

specified in the special specifications whichever is greater.

The applied cement rate shall be verified on field samples using AASHTO T-211 test this rate shall not differ from the approved percentage by more than 10% of the

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rate specified in the design job mix formula providing that the total difference should

not exceed, 0.5 % whichever is lesser.

Thickness of each constructed layer shall be measured after verification of

compaction by taking five random core samples and it is possible to use the field

density test hole for this purpose. The thickness accepted for determining paymentfactor shall not be less than the approved thickness minus 2 cm or 10 % of the thickness

shown on the drawings whichever is lesser.

6.5.5.5 Construction of Joints:

Joints shall be executed between adjacent sections constructed in consecutive

days or when constructing adjacent sections finished more than 30 minutes ago. Joint

construction shall be done by cutting edge of constructed layer straight and

perpendicular to a distance that extends up to the area where the surface regular with

constant slope and the cut width shall be not less than 10 cm. These cut faces shall be

wetted properly before starting the spreading of the new materials. The prepared joints

shall be protected at the end of each working day by wooden boards or other materialsaccepted by the Engineer.

When the pavement surface is asphalt concrete, transverse contraction joints

shall be performed for the full width of layer, with at interval not more than 10 meters,

and filled with the required filler materials. No need for performing contraction joints

when using a cement concrete surface layer. The cutting of contraction joints shall be

within the first five days after finishing of compaction, and joints shall be cleaned from

loose materials, and filled with filler material, providing that the level of sealing

materials shall not exceed the level of layer surface. The selection of filler type and

method of construction shall be in accordance with the requirements of division 14 of


6.5.5.6 Curing:

Cement treated base surface shall be kept in wet state by water spraying for a

period not less than 7 days providing that spraying shall start immediately after

finishing of compaction process and the layer curing can be done using soaking method

after making confining water perms on its surface or covering it with wetted sacks.

These sacks shall be rewetted using water for minimum two days and recovered with

the plastic sheets after each wetting process.

Moisture content of constructed layer surface can be maintained, by coveringthat surface with emulsified asphalt curing membrane composed from equal percent of

asphalt and water conforming to requirements indicated in paragraph (6.5.2.5) of this

section. The asphalt curing membrane shall be sprayed in a rate of 0.9-1.13 Litre/m2

based on the experimental section. Prior construction of asphalt curing membrane the

constructed surface shall be wetted with water for a minimum 24 hours period.

The asphalt curing membrane shall be executed according to construction

requirements of asphalt Base indicated in the division eight (8) of these general

specifications. Contractor shall be responsible for repairing any damage caused to

asphalt membrane or cement treated base.

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6.5.6 Traffic Control:

Contractor shall take all necessary requirements for traffic control during

construction and curing periods, and prevent movements of any equipment over the

treated layer before, the end of curing period, except water distributors are allowed to

pass providing that it should not cause any damage in the treated layer. Contractor shall

be responsible for maintenance and repair until construction of the next layer is allowed.

6.5.7 Finishing Requirements:

Cement treated Base shall be constructed according to dimensions, slopes and

thickness indicated on drawings and special specifications, providing that the difference

between constructed layer thickness and required thickness shall not exceed 2 cm or 10

% of the approved thickness whichever is lesser.

The final surface levels of constructed layer shall not differ from the specified

levels by more than 10 mm. The final levels shall verified on basis of 5 points cross

section measurements taken every 25 m interval, providing that the number of the

sections shall not be less than 5 for each 2000 square meters of constructed layer.

The surface smoothness shall be verified visually and by using straight edge, 3

meters long in five (5) locations, and the clearance between straight edge bottom and

the constructed surface between any two adjacent points shall not exceed 6 mm.

6.5.8 Acceptance:

Contractor shall control the quality of cement treated base through performing

all the required arrangements to insure that materials, methods and the completed works

meet the quality requirements specified in these specifications and other contract

documents.

The Ministry has the right to ensure quality of constructed works by verifying

contractor's quality control procedures either, through direct supervision of quality

control activities, or through performing quality assurance procedures, neutrally, on a

sufficient number of representative samples, to determine the level of construction and

to accept or reject the constructed work, on basis detailed in division 17 of this

specifications except otherwise indicated in the special specifications and other contract

documents.

1. Quality Control:

Contractor shall control the quality of materials and constructed works, andmonitor, record and analyze results, draw quality charts for critical properties and

perform all required tests and measurements indicated in Table (6.5.3).

Contractor shall submit to the Engineer with copies of all the measurements,

reports tests results and he shall apply all the requirements stated in item 17.1.1 of this

specifications.

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Table 6.5.3: Quality control for cement treated Base

Work Properties Test methodSampling

locationsFrequency of sampling Requirements

Aggregate

gradation

AASHTO

T-27, T-11

Aggregate

quality

requirements

All

requirements

indicated in

Table 6.5.2

3 tests on different samples

from each source and atapproval of design job mix

formula, or when the source

changed or properties of

constructed works is changed,

and five tests on different

samples taken in time interval

for each 5000 cubic meters from

each source during construction

Paragraph

6.5.2.2Raw

materials

Cement

Source

guarantee

certificate

At source

At starting of material supply

and whenever source is changed

Paragraph

6.5.2.1

Aggregategradation

AASHTOT-(27, 11)

Paragraph6.5.3.2

Moisture

/Density

relationship

AASHTO

T-134

Paragraph

6.5.3.2

Aggregate

quality

requirements

All

requirements

indicated in

Table 6.5.2

Table

6.5.2

Cement

percent

AASHTO

T-211

3 tests when starting of

production and one test for each

5000 cubic meters from

produced mix or when

properties of constructed work

is changed.

Paragraph

6.5.3.2.4

Materials

and mix

during use

unconfined

compressive

strength

AASHTO

T-22

In the

plant

Same other properties rate with

necessity for preparing samples

and maintaining them according

to AASHTO T-(134,126)

Paragraph

6.5.3.2

unconfined

compressive

strength

AASHTO

T-22

Paragraph

6.5.5.4

Cement

percent

AASHTO

T-211

3 tests at starting of construction

and one test each 10000 square

meters of treated layer and

when properties are changed.

Samples of strength test shall be

prepared and maintained

according to AASHTO T(134,

126) test.

Paragraph

6.5.5.4

Field densityAASHTO

T-(191, 205)

3 samples immediately after

compaction.

Paragraph

6.5.5.4

thickness Core samples

One measurement each day or

for each 2000 square meters of

constructed layer.

Paragraph

6.5.5.4

Dimensions

and levels

Survey

measurements

Cross sections each 25 meters

or 5 sections each 2000 square

meters whichever greater.

Item

6.5.7

Constructed

Works

Surface

smoothnessStraight edge

At site

5 measurements each 2000

square meters or measuring

between each approved twocross sections whichever

greater.

Item

6.5.7

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The Ministry has the right to ensure the quality of the materials and completed

works through carrying out or ordering others under its direct supervision to carry out

the necessary tests and measurements, and checking the completed work for each or

some quality control items specified in Table (6.5.3).


compare these records statistically with the results obtained by quality assurance

procedure as specified in division 17 of these specifications, and inspect contractor’s

equipments, technical staff, and measurement and construction methods, to determine

the degree of compliance of measurements and constructed methods with the approved

requirements.



method specified in division 17 of this specifications except otherwise specified by the


6.5.9 Measurements:

The cement treated base shall be measured in cubic meters or as specified in the

special specification after its laying and compaction according to the required thickness

and within the dimensions and levels indicated on the drawings or according to the

Engineer's instructions. When special specifications require separate cement

measurement, the actually used quantity of cement shall be measured in tons. No

measurements shall be performed for purpose of payments for materials laid outside the

limits of works indicated on the drawings or special specifications or specified by the

Engineer.

6.5.10 Payment:

Payment shall be made for actually constructed and technically accepted works

within the approved limits and dimensions and according to Contract prices or reduced

prices because of quality assurance implementation when indicated in contract

documents. The paid amounts are considered full compensation for production,

supplying, mixing, transporting, spreading and compacting of materials, finishing of

works, benefits, revenues, fees and third party payments, provisions and operation of

machines and equipments, labor, tests, measurements and all requirements for

constructing the works in accordance with drawings, special and general specifications.

Payment shall be made according to one or more of the items indicated in the Table(6.5.4) without contradiction with contract documents.

Table 6.5.4: Payment Items for Cement Treated base course

Item No. Work type Unit

6.5.1 Cement treated Base m3

6.5.2 Cement Ton

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6.6 Emulsified Asphalt Treated Base:

6.6.1 Work description:

This Section consists of furnishing and cold-mixing aggregate and emulsified

asphaltic material, hauling, spreading, compacting and finishing the emulsified asphalt

treated base to the lines, grades and thickness shown on the plans, all in accordance withthe these General Specifications, Special Specifications, and as directed by the

Engineer.

There are three of emulsified asphalt treated base mixes, which are classified

according to aggregate gradation used in these mixes as shown in Table (7.3.5) in these

General Specifications. They are type-I (open graded), type-II (dense graded), and type-

III (sand graded).

Type-I emulsified asphalt treated base mix is produced at ambient temperature

(cold-mix) and only by central mixing. However, the emulsified asphalt treated base

mixes Type-II and type-III may be produced in the ambient temperature (cold-mix) byone of the following three methods:

• Central mixing in a continuous mixing pugmill.

• Central mixing in a batch plant.

• Mix on-road by using a mobile mixing unit.

6.6.2 Materials:

Asphalt material: the material shall be from emulsified asphalt categories MS-2 or

MS-2h or CMS-2 or CMS-2h or SS-1h or CSS-1 or CSS-1h so that it complies with the

quality requirements indicated in Tables (7.2.5) to (7.2.7) in these General

Specifications. The selected asphaltic materials shall provide the required coating

requirements stated in Item 6.6.3.

Aggregate: Aggregate gradations 1 (open-graded), 2 (dense-graded), and 3 (sand-

graded) from Table 7.3.5 in these General Specifications, shall be used for preparing the

emulsified asphalt treated base mixes provided that they achieve the quality

requirements indicated in Table (7.3.1) (Types 4, 5, 6) in these General Specifications.

The combined aggregate shall achieve the approved gradation requirements within the

allowed variation limits indicated in Table (6.6.1).

Water: Water shall be free of matter deleterious to the quality of the emulsified asphalt

treated mixture.

Cement: It shall be from Portland cement type (I) or (II) which is compliant with the

requirements indicated in Item 7.3.4 in these General Specifications

Table 6.6.1: Allowable tolerance limits for total aggregate

Sieve size Variation percent points

9.75 mm (3/8 inch) ± 8

4.75 mm (No. 4) and more ± 7

2.36 mm (No. 8) and 0.300mm (No. 50) ± 6

0.150 mm (No. 100) ± 4

0.075 mm (No. 200) ± 2Asphalt content ± 0.40

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6.6.3 Emulsified Asphalt Treated Base Mix:

6.6.3.1 Job Mix Formula:

Contractor, before starting the execution of the Emulsified asphalt treated base

by thirty (30) days, shall submit to the Engineer a full technical report prepared by an

approved specialized agency including the mix design and job mix formula (JMF)which should be prepared according to the basic asphalt emulsion guide (MS-19)

published by the American Asphalt Institute using and ASTM D-1559 unless otherwise

stated in the Special Specifications. The JMF shall conform to the requirements shown

in Table (6.6.2).

Table 6.6.2: Quality requirements for emulsified asphalt treated mixes (MS-19)

Property Minimum limit Maximum limit

Marshall stability. Kilogram ASTM D 1559 227 -

Stability loss, percent % - 50

Air voids, percent 2 8Absorbed moisture rate after 4 soaking days, % - 4

Aggregate coating, percent ASTM D 244 % 50 -

The Contractor shall submit the JMF together with the following information:

1. Necessary data on aggregate source, gradation, and properties related to

crushing, gradation and other quality requirements stated in Item 6.6.2.

2. Type and grade of the emulsified asphalt materials to be used.

3.

All test results of the trial experimental mixes and mix design.

4. Asphalt content based on the total dry weight of the mix.

5.

Percentage of the Portland cement, as required, of the total dry weight of themix.

6.

Percentage of additional mixing water on the basis of the total dry weight of the

mix.

7. Total liquid percentage (asphalt material and water) at compaction based on the

dry total weight of the mix.

8. Maximum theoretical density according to ASTM D-2041.

9.

Type and site of mixer intended for use in preparing each mix to be submitted.

10. Date of commencing production of the emulsified asphalt treated base mixes.

11. A list for all the equipment to be used.

The Engineer shall be provided access to the materials sampling and testingoperations at all times.

Contractor shall supply to the Engineer one hundred (100) kilogram samples of

each individual aggregate size, eight (8) liters of asphaltic material and, when used,

sufficient quantities of mineral filler and chemical admixture to check design JMF and

all representing materials which the Contractor proposes to furnish.

6.6.3.2 Job Mix Formula Acceptance Procedures:

After Contractor submits the proposed job formula with all its appendices as

indicated in the previous item, the Ministry shall review the job mix according to the

following steps:

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1. Assure that the report contains all requirements. If it does not contain all

required information, it shall be returned within seven (7) days to the Contractor

for further action and resubmission by the Contractor.

2.

If the proposed JMF contains all required information but fails to meet all of the

requirements specified, it should not be accepted by the Engineer and will be

returned to the Contractor within fourteen (14) days. The Contractor shall prepare and submit to the Engineer a revised JMF conforming to the

requirements specified.

3.

It is not allowed to commence production of the emulsified asphalt treated base

mix until the Engineer has already issued his acceptance of the JMF.

4. The first-day work shall be considered as a field control strip. It shall be assured

that mix is constructible in terms of spreading and compaction.

5.

The Engineer's acceptance of the job mix formula does not release the

Contractor from his responsibility for producing the emulsified asphalt treated

base mixes, which are compliant with all the specified requirements.

6. The Contractor shall not alter the methods of manufacturing, screening, mixing,

stockpiling of aggregate, or production of asphalt mixtures since this alterationwill mandate re-evaluation of JMF as stated in previous Subitem.

6.6.4 Equipments:

The Contractor shall furnish and operate sufficient equipment to execute the

asphaltic concrete work within the Contract time in accordance with his program of

work as approved by the Engineer. This equipment shall conform to the following

requirements:

1. The mobile mixer shall not be used for producing open-graded base mixes.

2. Water added to the mix shall be applied through volumetric rate meter,

registering in liters per minute, which will accurately measure the flow of water.

The flow of water shall be interlocked with the flow of aggregate, asphalticemulsion material and additives, if required.

3. Portland cement shall be introduced into the mixture through a positive auger or

belt feeder.

4. Cold-feed proportioning controls shall be used.

6.6.5 Weather Limitations:

Emulsified asphaltic treated mixtures shall not be placed on any surface with

stagnant water or frozen surface, during dust or sand storms, or when the air

temperature is less than fifteen (15) degrees Celsius.

6.6.6 Constructions:6.6.6.1 Emulsified Asphalt Material Preparation:

The emulsified asphalt material shall be stored in temperatures within the ranges shown

in Table (6.6.3). The emulsified asphalt materials shall be protected from freezing due

snow and shall be pulverized and rotated in regular intervals to ensure its uniformity

and regularity. Forced air shall not be used for agitation process.

Table 6.6.3: Storing temperature ranges for emulsified asphalt materials.

Storing temperature (Degrees Celsius)Emulsified asphalt Material

Minimum Maximum

SS-1, SS-1h, CSS-1, CSS-1h 10 60MS-2, CS-2h, CMS-2, CMS-2h 50 85

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6.6.6.2 Aggregate Preparation:

Aggregate shall be stockpiled and transported from stockpiles according to the

requirements of Item 7.3.6 in these General Specifications

6.6.6.3 Central Mixing:

Unless the Special Specifications allow, all emulsified asphalt treated base types(I, II, and III) may be produced in a central mixing plant. Aggregate, the emulsified

asphalt material, added water, Portland cement, and other additive materials, when

required, may be proportioned by approved JMF. Mixing shall be executed according

to the following steps:

1. The aggregate shall be fed from storage to the mixing chamber using a belt

feeder equipped with devices by which the rate of aggregate feed can be

determined while the plant is in full operation. Aggregate feed and the asphaltic

emulsion material-metering pump shall be mechanically or electrically

interlocked in a manner that maintains a constant ratio of aggregate and

asphaltic emulsion material.

2.

Portland cement, when required, shall be introduced into the dry aggregate onthe belt feeder and shall be mixed thoroughly before adding water or emulsified

asphalt.

3. Mixing water, when required, shall be introduced into the aggregate through a

spray bar mounted at such a point that the water is added as the aggregate enters

into the mixing chamber.

4.

The asphaltic emulsion material shall be introduced into the mixing chamber

through a spray bar that can be adjusted to vary mixing times between five and

thirty (5-30) seconds.

5. The aggregate, water and Portland cement as required, and asphaltic emulsion

material shall be mixed until the aggregate has been coated and a uniform and

homogeneous mixture has been obtained.

6. Type (I) open-grade emulsified asphalt treated base mix shall be discharged

directly into hauling equipment or stored in bins or silos. Type (I) open-graded

emulsified asphalt treated base mix shall not be stored on the ground.

7. Type (II) and Type (III) emulsified asphalt treated base mixes may be

discharged directly into hauling equipment or stored. Type (II) and Type (III)

base mixes shall not be stored for periods longer than forty-eight (48) hours

without prior written approval from the Engineer.

6.6.6.4 Road Mixing:

When the Special Specifications allow, types (II) and (II) of the emulsifiedasphalt treated base mixes may be mixed using a propelled mobile mixing plant. The

travel plant shall be capable of producing a uniform, properly coated, emulsified asphalt

material-aggregate mixture conforming to the requirements of the JMF. Emulsified

asphalt material and aggregate proportioning devices shall be keyed to the rate of

forward travel of the mixer, or interlocked to ensure a constant asphaltic emulsion

material-aggregate blend. Multiple passes of the travel plant may be required for higher

emulsified asphalt material contents to achieve required uniformity of mix.

6.6.6.5 Spreading and Compaction:

The surface to receive emulsified asphalt treated base shall conform to the

compaction and other requirements for the material involve. When the surface does not

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conform to compaction and other requirements for the material involved, the

Contractor, at his own expense, shall correct all deviations.

When the surface to receive emulsified asphalt treated base is a soil subgrade,

aggregate subbase or aggregate base, and the total thickness of the asphaltic emulsion

treated base and surface course is less than ten (10) centimeters, the surface shallreceive a prime coat in accordance with the requirements specified in Section 8.3 in

these General Specifications. The prime coat shall be allowed to cure for at least forty-

eight (48) hours before placement of emulsified asphalt treated base.

Type (I) open-graded emulsified asphalt treated base shall be spread using a

self-propelled paving machine. The maximum thickness of one lift shall not exceed ten

(10) centimeters. Immediately after spreading, each lift shall be compacted with (1) one

coverage of a steel-drum tandem roller weighing not less than ten thousand (10,000)

kilograms. After the initial coverage, choke stone shall be uniformly spread across the

surface of the open-grade base at a rate between seven and thirteen (3-5) kilograms per

square meter using a self-propelled spreading device. Immediately after spreadingchoke stone, the open-graded base shall receive three (3) additional coverages with a

steel-drum tandem roller weighing not less than ten thousand (10,000) kilograms. After

completion of compaction, surplus choke stone shall be removed by sweeping. Each lift

of open-graded base shall be allowed to cure for a period not less than seventy-two (72)

hours before spreading successive lifts.

Type (II) and Type (III) emulsified asphalt treated base may be spread using a

self-propelled paving machine, aggregate base spreader, or other device which results in

a base that is smooth, has a uniform texture, conforms to planned and specified

thickness, and is within the lines and grade shown on the plans. The maximum

thickness of one lift shall not exceed ten (10) centimeters unless otherwise approved by

the Engineer provided sufficient Portland cement is added to the mixture to accelerate

curing and the Contractor demonstrates that curing is effective.

Each lift shall be compacted using a steel-drum tandem roller weighing not less

than ten thousand (10,000) kilograms until the relative compaction is at least ninety-one

(91) percent of the theoretical maximum density determined from test method ASTM

D-2041.

Each lift of Type (II) and Type (III) emulsified asphalt base shall be allowed to

cure for the period specified in the Special Specifications, or for three to five (5) days,

or, when Portland cement is added to the mixture, for such shorter period as approved by the Engineer. In all cases, the next layer shall not be placed and the traffic shall not

be allowed before the emulsified asphalt treated base is cured.

6.6.6.6 Finishing:

When it is shown on the drawings or specified in the specifications, the

emulsified asphalt treated base layers of all types shall be covered with a layer of

asphalt slurry seal type (3) sand compliant with the requirements of item 10-3 of these

General Specifications.

When the surface is tested by a four (4) meter straight edge, the deviations shall

not be more than five (5) millimeters in the longitudinal direction or ten (8) millimetersin the transverse direction are allowed.

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6.6.7 Traffic control:

The Contractor shall take effective action to control all traffic in accordance

with the “Manual of Traffic Control through Work Zones” issued by the Ministry of

Municipalities and Rural Affairs in 1421H (2001).

6.6.8 Work Acceptance:The Contractor shall apply quality control procedures for emulsified asphalt

treated base works to ensure that the materials used and the executed work conform to

these General Specifications and other Contract’s Documents.

The Ministry shall assure the quality of production by checking that the

Contractor is performing the quality control procedures in correct manners. The

Ministry may have a direct supervision on the quality control system or by applying

quality assurance procedures in an independent unbiased way, on adequate number of

samples to judge the execution level and decide whether to accept or reject the work.

Division 17 in these General Specifications shall be used for this purpose, unless stated

otherwise in the Special Specifications or Contract’s Documents.

6.6.8.1 Quality Control:

The Contractor shall perform all required tests and measurements, and shall

collect, document, and draw the critical property diagrams to ensure that the raw

materials at source, materials while work execution, emulsified asphalt treated base

produced, and the executed work are within acceptable limits. The tests may be

performed at The Contractor’s laboratory or at an independent laboratory, approved by

the Ministry. The Contractor shall submit copies of all test results to the Engineer.

Table (6.6.4) shows the tests that the Contractor shall perform on raw materials and

mixes, the frequency of these tests, and the allowance limits. The Contractor shall

submit copies of all tests to the Engineers and shall apply all requirements detailed in

Item 17.1.1 in these General Specifications.

6.6.8.2 Quality Assurance:

The Ministry reserves the right, at any time, to assure the quality of materials

and executed work by performing or ordering the Contractor to perform, under its direct

supervision, some or all quality control tests that are shown previous Sub item. The

Ministry has also the right to inspect all Contractors' quality control test records and

compare them with its quality assurance test done according to Division 17 in these

General Specifications. Ministry may inspect Contractor's laboratory, devices, technical

staff, and testing methods to assure the full adequacy and capability of the Contractor toexecute the work according to standard approved methods.

6.6.9 Measurements:

Each type of the emulsified asphalt treated base shall be measured in cubic

meters according to its position and its compaction according to the specified thickness

and within the lines and levels shown on the drawings and according to the Engineer's

instructions. It is not allowed to perform any measurements for the materials laid

outside the allowed limits for payment purposes.

Mineral fillers, chemical admixtures and asphalt modifiers used by the

Contractor to meet the Job Mix Formula (JMF) requirements will be consideredsubsidiary to the construction of the emulsified asphalt treated base and shall not be

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measured separately unless specifically stated in the Special Specifications and listed in

the Bill of Quantities. When they are listed separately they shall be measured in liters,

kilograms, or tons.

Table 6.6.4: Quality control procedures for the emulsified asphalt treated base

Work PropertiesTest

Method

Sample

locationSampling frequency Requirements

Asphalt

emulsion

Quality

requirement

s tests

Tables

7.2.5 to 7.2.7

Cement

Quality

requirement

s tests

Compliance certificate at

supply starting and

whenever source is changed Quality

requirements

in item 7.3.4

Raw

materials

Aggregate

Quality and

Gradation

Requiremen

ts tests

Source

Three (3) tests on different

samples from each source atsource approval or JMF,

change source. Minimum

of five (5) tests on samples

taken at different times

every five-thousand (5000)

cubic meter for each source

at production

Tables 7.3.1

and 7.3.5

Aggregate

Gradation (dry

mix)

AASHTO

T-27

Three tests for mix design

and test each week and

whenever source is changed

Table 7.3.5

Aggregate

coating in the

mix

ASTM D-

244

StockedMaterials Three tests to use theasphalt materials and the

aggregates and for mix

design and test whenever

source is changed

Table 6.6.2

Aggregate

Gradation and

Asphalt content

in mix

AASHTO T-

164/T-27

Table 7.3.5,

Table 6.6.1,

and JMF

Requirement

Materials

in use

Marshall

stability and

Loss

ASTM D-

1559

Mixing

plant or

behind

the paver

One (1) test for each five

hundred (500) cubic meters

of each layer or a day-work,

whichever minimumTable 6.6.2

Compaction AASHTOT-310

Test for each one thousand(1,000) square meters

Sub item6.6.6.5

ThicknessASTM D-

3549

Test for each one thousand

(1,000) square meters

Contract

documents

Surface layer

smoothness

Sub item

6.6.6.6

Straight edge measuring

method for every day work

Sub item

6.6.6.6Executed

workMeasuring

dimensions,

levels, slopes

and

smoothness

Geometric

measureme

nts

Project

siteTransverse segments every

twenty-five (25) meters or

five segments every one

thousand (1000) meters,

whichever the maximum

Contract

documents

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The surface treatment shall be measured by square meters as indicated in

Division 10 of these General Specifications.

Choke stone will be considered subsidiary to the construction of asphaltic

emulsion treated base and will not be measured.

6.6.10 Payment:

Payment shall be made at the contract unit price, or adjusted contract unit price,

per cubic meter measured as described in the pervious Item for each type emulsified

asphalt treated base and all related items listed in the Bill of Quantities.

The above prices and payment shall cover and be full compensation for

furnishing labor, materials, equipment, tools, and incidentals necessary for completing

all work involved in construction and acceptance of emulsified asphalt treated base.

Table 6.6.5: Emulsified asphalt treated base mix pay items

No. Pay Item Pay units

6.6.1 Emulsified asphalt treated base type ___________ Cubic meter

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