Surface Courses and Pavement (241199)

64
ITEM SP SURFACE COURSES AND PAVEMENT SP-1-1 GENERAL This section outlines the requirements and procedure for constructing surface courses. The material to be used are referenced to specifications and testing procedure of either American Association of state Highway and Transportation officials (AASHTO) or the American Society of Testing materials (ASTM) as described in the latest editions of the AASHTO and ASTM standards. Where samples of materials are to be taken for laboratory tests and approval, the methods to be utilized are full described in these references and shall be followed unless directed otherwise, in writing, by the Engineer. All materials, which don't conform to the requirements of these specifications, will be rejected whether in place or not. They shall be removed immediately from the site of the work at the contractor expense. While subgrade/subbase and paving operations are under way, public traffic shall be permitted to use the shoulders when authorized and, if half width paving methods are used, shall also be permitted to use the side of the roadbed opposite the one under construction. When sufficient width is available, a passage way wide enough to accommodate at least 2 lanes of traffic shall be kept open at all times at locations where subgrade/sub base and paving operations are in active progress. At location where traffic is being routed through construction under one way controls and when ordered by the engineer, the movement of the contractors equipment from one portion of the work to another shall be governed in accordance with such one way controls. Water shall be applied as a dust palliative if ordered by the Engineer for the alleviation of dust nuisance. In order to expedite the passage of public traffic, through or around the work and where ordered by the Engineer, the contractor shall install signs, lights, barricades and other facilities, shall be included in respective work item. Whenever work as being performed adjacent to a lane carrying traffic, the edge of lane or edge of pavement shall be delineated /home/website/convert/temp/convert_html/5695d40e1a28ab9b02a01e6a/document.doc

description

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Transcript of Surface Courses and Pavement (241199)

Page 1: Surface Courses and Pavement (241199)

ITEM SP SURFACE COURSES AND PAVEMENT

SP-1-1 GENERAL

This section outlines the requirements and procedure for constructing surface courses.

The material to be used are referenced to specifications and testing procedure of either American Association of state Highway and Transportation officials (AASHTO) or the American Society of Testing materials (ASTM) as described in the latest editions of the AASHTO and ASTM standards. Where samples of materials are to be taken for laboratory tests and approval, the methods to be utilized are full described in these references and shall be followed unless directed otherwise, in writing, by the Engineer.

All materials, which don't conform to the requirements of these specifications, will be rejected whether in place or not. They shall be removed immediately from the site of the work at the contractor expense.

While subgrade/subbase and paving operations are under way, public traffic shall be permitted to use the shoulders when authorized and, if half width paving methods are used, shall also be permitted to use the side of the roadbed opposite the one under construction. When sufficient width is available, a passage way wide enough to accommodate at least 2 lanes of traffic shall be kept open at all times at locations where subgrade/sub base and paving operations are in active progress.

At location where traffic is being routed through construction under one way controls and when ordered by the engineer, the movement of the contractors equipment from one portion of the work to another shall be governed in accordance with such one way controls.

Water shall be applied as a dust palliative if ordered by the Engineer for the alleviation of dust nuisance.

In order to expedite the passage of public traffic, through or around the work and where ordered by the Engineer, the contractor shall install signs, lights, barricades and other facilities, shall be included in respective work item.

Whenever work as being performed adjacent to a lane carrying traffic, the edge of lane or edge of pavement shall be delineated by placing temporary portable delinators adjacent thereto.

Whenever the contractor's operations create a condition hazardous to traffic or to the public, he shall furnish, erect and maintain, at his own expense, such fences, barricades, lights, signs and other devices as are necessary to prevent accidents or damage or injury to the public. The contractor shall also furnish such flagmen and guards as are necessary to give adequate warning to the traffic or to the public or any dangerous conditions to be encountered.

Should the contractor appear to be neglectful or negligent in furnishing warning and protective measures as above provided, the Engineer may direct attention to the existence of a hazard and the necessary warning and protective measures shall be furnished and installed by the contractor at his expense. Should the Engineer point out the inadequacy of warning and protective measures, and require additional measures, such action on the part of the Engineer shall not relieve the contractor from responsibility for public safety or abrogate his obligation to furnish and pay for these services.

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SP-2-2 ASPHALTIC MATERIALS

SP-2-3 ASPHALT CEMENT

Asphalt Cement shall be oil asphalt, or a mixture of refined liquid asphalt and refined solid asphalt, prepared from crude asphaltic petroleum. It shall be free from admixture with any residues obtained by the artificial distillation of coal, tar, or paraffin and shall be homogeneous and free from water. No emulsification shall occur when a 30 gram sample is boiled for 2 hours with 250 cubic centimeters (16 cubic inch) of distilled water in 500 cubic centimeters (32 cubic inch) Erlenmeyer flask equipped with a reflux condenser.

Asphalt Cement shall be classified by penetration and when tested in accordance with the standard methods of tests of the AASHTO, the grades of asphalt shall conform to the requirements set forth in Table SP-2. The grade of asphalt to be used shall be in accordance with these specifications or the Special Provisions or as directed by the Engineer.

SP-3-3.1 Cut-back Asphalt

Liquid asphalt (cut back) shall consist of materials conforming to the following classifications. When tested in accordance with the standard methods of tests of the AASHTO, the grades of liquid asphalt shall conform to the requirements specified in the Table SP-3 and SP-4.

Medium curing products designated by letters MC shall consist of asphalt cement fluxed or blended with a kerosene solvent.

Rapid curing products designated by the letters RC, shall consist of asphalt cement with a penetration of approximately 85 to 100, fluxed or blended with naphtha solvent.

SP-3-4 APPLICATION TEMPERATURES

TABLE-SP-1

Application Temperature

Spray Mix

a) Asphalt 200 As required to achieve

Cement(max) viscosity of

75-150 secs. Say-bolt-Furol or (all grades)

a required to achieve a Kinematic Viscosity of 150-300 centistokes.

b) Cut-back orEmulsified asphalt

MS-70, RC-70 27-65 27-65MC-250 38-93 38-93RC-250 38-79 27-65MC-800 85-127 71-99

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RC-800 71-107 57-85SS-1, SS-1h 24-55 -RS-1 24-55 -RS-2 44-70

TABLE - SP - 2

Requirements for Asphalt Cement (AASHTO M 20)

PENETRATION GRADE 40 50 60 70 85 100 120 150 200 300

Min Mx Min Mx Min Mx Min Mx Min Mx

Penetration at 77 F 40 50 60 70 85 100 120 150 200 300

(25 C) 100g 5 sec.

Flash point, Cleveland 450 - 450 - 450 - 425 - 350 -

Open Cup, F (

C) (323) (323) (323) (218)(117)

Ductility at 77F 100 - 100 -1 100 - 100 - - -

(25C) 5 cm per min.cm

Solubility in trichlo- 99 - 99 - 99 - 99 -99 -

roethylene percent

Thin-film oven test,1/8 in. (3.2 mm),

325F (163C) 5 hr.

Loss on heating, - 0.80 - 0.8 - 1 - 1.3 - 1.5 -percent. Penetration,of residue,

percent of original. 58 - 54 - 50 - 46 -40 -

Ductility of residue

at 77F (25C) 5 cm. per min., cm. - - 50 - 75 - 100

- 100 -

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TABLE SP-3

Requirements for Medium-Curing Type Asphalt (AASHTO M82)

MC - 70 MC - 250 MC - 800 Min Max Min Max

Min Max

Water, percent - 0.2 - 0.2 - 0.2Flash point (tag. open cup), 38 - 66 - 66 -Degree C Kinematic Viscosity

at 60 C (140 F)(See Note 1) centistokes.. 70 140 250 500 8001 600

Distillation test:Distillate, percentage by volume of total

Distillate to 360C (680F)

to 225C (437F) 0 20 010 - -

to 260C (500F) 20 60 15 55 0 35

to 315 C (600 F) 65 90 60 87 45 80

Residue from distillation

to 360 C (680 F) volumepercentage of sample by different 55 - 67 - 75 -Tests on residue from distillation:Penetration, 100 g., 5 sec., at

25 C (77 F) 120 250120 250 120 250

Ductility, 5cm/min, cm (see note 2) 100 - 100 - 100 -

Solubility in Trichloroethylene, Percent 99.0 - 99.0 - 99.0 -

Tests on residue from distillation:

Absolute viscosity at 60 C, (See Note 4), poise 300 1200 300 1200 300 1200

MC - 30 MC - 300 0

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Min Max Min Max

Water, percent - 0.2 0.2 0.2Flash point (tag. open cup), 38 - 66 -

Degree C Kinematic Viscosity

at 60C (140F)(See Note 1) centistokes. 30

60

3000 6000

Distillation test:Distillate, percentage by volume of total

Distillate to 360C (680F)

to 225C (437F)

- 25

- -

to 260C (500F)

40 70

0 15

to 315C (600F)

75 93 15 75

Residue from distillation to 360C (680F)Volume percentage of sampleby difference 50 - 80 -

Tests on residue from distillation: Penetration, 100 g., 5 sec.,

at 25C (77F) 120 250 120 250 Ductility, 5cm/min, m (see note 2) 100 - 100 - Solubility in Trichloroethylene, percent 99.0 - 99.0 -

Tests on residue from distillation:

Absolute viscosity at 60C,

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(See Note 4), poise 300 1200 300 1200

Spot test (see note 3) withStandard Naphtha Negative for all grades

Naphtha xylene solvent% xylene

----------- do---------

Heptane xylene solvent% xylene

----------- do---------

Note 1. As an alternate, Saybolt Furol viscosities may be specified as follows:

Grade MC-70 Furol viscosity at 50C (122F) - 60 to 120 sec.

Grade MC-250 Furol viscosity at 60C (140F) - 120 to 250 sec.

Grade MC-800 Furol viscosity at 82.2C (180F) - 100 to 200 sec.

Note 2. If penetration of residue is more than 200 and its ductility at 25C (77F) is less that

100 cm., the material will be acceptable if its ductility at 15.5C (60F) is more than100 cm. (40 in)

Note 3. The use of spot test is optional. When specified, the Engineer shall indicate, whether the standard naphtha solvent, the naphtha xylene solvent or heptane xylene solvent will be used in determining compliance with the requirements, and also, in the case of xylene solvents, the %age of xylene to be used.

Note 4. In lieu of viscosity of residue, the specifying agency, at its own opinion can specify

penetration 100 g; 5 s at 25C of 120 to 250 for grades MC-30 , MC-70, MC-250 MC-800 and MC-3000. However, in no case will both be required.

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TABLE SP-4

Requirements for Rapid-Curing Type Asphalt (AASHTO M81)

RC - 70 RC - 250 RC - 800 RC - 3000 Min Max Min Max Min Max Min Max

Water, percent - 0.2 - 0.2 - 0.2 - 0.2

Flash point (tag. open cup), - - 27 - 27 - 27 -Degree C Kinematic Viscosity

at 60C (140F)(See Note 1) centistokes. 70 140 250 500 800 1600 3000 6000

Distillation test:Distillate, percentage byvolume of total distillate

to 190C (680F) 10 - - - - - - -

to 225C (437F) 50 - 35 - 15 - - -

to 260C (500F) 70 - 60 - 45 - 25 -

to 315C (600F) 85 - 80 - 75 - 70 -

Residue from distillation:

to 360C (680F) volumepercentage of sampleby difference 55 - 65 - 75

- 80 -

Tests on residue from distillation:

Absolute viscosity at 60oC(See note 3) Poise 600 2400 600 2400 600 2400

600 2400 Penetration, 100 g., 5 sec.

At 25C (77F) 80 20 80 120 80120 100 -

Ductility, 5cm/min,cm (see note 2) 100 - 100 - 100

- 100 -

Solubility in Trichloroethylene, percent 99.0 - 99.0 - 99.0 - 99.0 -

Spot test (see note 2) withStandard Naphtha Negative for all grades

Naphtha xylene solvent% xylene ----------- do---------

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Heptane xylene solvent% xylene ----------- do---------

Note 1. As an alternate, Saybolt Furol viscosities may be specified as follows:

Grade RC-70 Furol viscosity at 50C (122F) - 60 to 120 sec.

Grade RC-250 Furol viscosity at 60C (140F) - 125 to 250 sec.

Grade RC-800 Furol viscosity at 82.2C (180F) - 100 to 200 sec.

Note 2. The use of spot test is optional. When specified, the Engineer shall indicate, whether the standard naphtha solvent, the naphtha xylene solvent or heptane xylene solvent will be used in determining compliance with the requirements, and also, in the case of xylene solvents, the %age of xylene to be used.

Note 3. In lieu of viscosity of residue, the specifying agency, at its own opinion can specify

penetration 100 g; 5 s at 25C of 80 to 120 for grades RC-70 ,RC-250, RC-800 and RC-3000. However, in no case will both be required.

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ITEM SP1 BITUMINOUS PRIME COAT SP-9-1 DESCRIPTION

This work shall consist of furnishing and applying asphaltic material on a prepared and untreated surface in accordance with these specification and to the width shown on the typical cross-section or as directed by the Engineer.

SP-9-2 MATERIAL REQUIREMENTS

Asphaltic material shall conform to the requirements of Item SP Asphaltic Materials, Cut-back Asphalt, as specified in the Bill of Quantities.

SP-9-3 CONSTRUCTION REQUIREMENTS

Prime coats shall be applied only when the surface to be treated is dry. No application shall be made when the weather is foggy or rainy, or when the atmospheric temperature is below 15C unless otherwise directed by the Engineer.

SP-9-3.1 Equipment

The liquid asphaltic material shall be prayed by means of a pressure distributor of not less than 1136 liter capacity, mounted on pneumatic tyres of such width and number that the load produced on the road surface will not exceed hundred (100) Kg per cm width of type. It shall be recognized manufacture.

The tank shall have a heating device able to heat a complete charge of asphaltic liquid upto one hundred eighty (180) degree C. The hearting device shall be so that overheating will not be occur Consequently. The flames must not touch directly on the casting of the tank containing the asphaltic liquid or gases therefrom. The Contractor will be responsible for any fire or accident resulting from heating of bituminous materials. The liquid shall be circulated or stirred during the hearing. The tank shall be insulated in such a way that the drop in temperature when the tank is filled and not heated, will be less than two (2) degree C per hour. A thermometer shall be fixed to the tank in order to be able to control continuously the temperature of the liquid. The thermometer shall be place in such a way that the highest temperature in the tank is measured. The tank shall be furnished with a device that indicates the contents. The pipes for filling the tank shall be furnished with an easily interchangeable filter.

The distributor shall be able to vary the spray width of the asphaltic liquid in steps of maximum 10cm, to a total width of four (4) cm. The spraying bar shall have nozzles from which the liquid is sprayed fan-shaped on the road surface equally distributed over the total spraying width.

The distributor shall have a pump for dosing the liquid driven by a separate mortar, or the speed of the pump for dosing the liquid driven by a separate mortar, or the speed of the pump shall be synchronized with the speed of the distributor. The pump shall be furnished shall with an indicator showing the performance in liters per minute. At the section side the pump shall have a filter easily exchangeable. A thermometer shall be fixed, which indicates the temperature of the liquid immediately before it leaves the spraying bar.

The distributor shall be furnished with a tachometer indicating the speed in meter per minute. The tachometer shall be visible from the driver's seat. The prescribed quantity to be spread on any square meter does not exceed 10%. The distributor shall be equipped with a device for hand spraying of the bituminous liquid of contractor want to use an equipment other than specified above in that case alternative equipment should be approved by the Engineer.

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SP-10-3.2 Application of asphaltic Material

Immediately before applying the prime coat, the full width of surface to be treated shall be swept by hand broom to remove all dirt and other objectionable material. Power broom may be approved by the Engineer if sufficient labour is not available. Where required by the Engineer, the surface shall be lightly sprayed with water but not saturated. Asphaltic materials shall be applied by means of hand operated pressure distributor and at a temperature stated in Item SP for the particular asphalt being used. Cut-back asphalt 0.65 to 1.75 liters/sq. meter but the exact rate shall be specified by the Engineer.

The prime coat shall be left undisturbed for a period of at least 24 hours, and shall not be opened to traffic until it has penetrated and cured sufficiently so that it will not be picked up by the wheels of passing vehicles. The Contractor shall maintain the prime coat until the next course is applied. Care shall be taken that the application of bituminous material is not in excess of the specified amounts; any excess shall be blotted with sand or similarly treated. All areas inaccessible to the distributor shall be sprayed manually using the device for hand spraying from the distributor.

The surface of structures and trees adjacent to the area being treated shall be protected in such manner as to prevent their being spattered or marred.

SP-10-4 MEASUREMENT AND PAYMENT

The quantities of liquid asphalt; measured as stated above shall be paid for at the contract unit price per units of Area, which payment shall be full compensation for furnishing all labor, materials, tools, equipment and incidentals and for performing all the work involved in applying prime coat, complete in place, as shown on the drawings and in accordance with these specifications:

Pay Item No. Description Measurement

SP1 (a) Cut-back Asphalt for Bituminous Prime Coat

M2

SP1 (b) Emulsified Asphalt for bituminous prime coat.

M2

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ITEM SP2 BITUMINOUS TACK COAT SP-11-1 DESCRIPTION

This work shall consist of furnishing and applying material on a previously prepared course, complete in accordance with these specifications and to the width shown on the typical cross-section or as directed by the Engineer.

SP-11-2 MATERIAL REQUIREMENTS

Aggregate material shall conform the requirements of item SP-2-2. Asphaltic Materials, for emulsified asphalt, or cut-back asphalt as called for in the Bill of Quantities.

SP-11-3 CONSTRUCTION REQUIREMENTS

Normally tack coats shall be applied only when the surface to be treated is dry, however cut-back asphalt is specified, application may be made on a reasonable moist surface. No application shall be made when the weather is foggy or rainy.

SP-11-3.1 EQUIPMENT

Equipment shall conform in all respects to the provisions under item SP-9-3.1.

SP-11-3.2 APPLICATION OF ASPHALTIC MATERIAL

Immediately before applying the tack coat, the full width of the surface to be treated shall be created of loose and foreign material by means of a power broom or power blower, supplemented as necessary by hand sweeping. Where required by the Engineer, immediately prior to the application of the tack coa, the surface shall be lightly sprayed with water but not saturated. Asphaltic material shall be applied by means of a pressure distributor, at the temperature stated in item SP-3-4 for the particular material being used. Rates of application of the cut-back asphalt shall be within the following range:

0.2 to 0.7 liters per square meter; the exact rate shall be specified by the Engineer.

Case shall be taken to the application of asphaltic material is not in excess of the specified amount; any excess existing shall be blotted by sand or similarly treated. All areas inaccessible to the distributor shall be treated manually using the device for hand spraying from the distributor. The surfaces of structures and trees adjacent to the area being treated shall be protected in such a manner as to prevent their being spattered or married. Where no convenient detour is available for traffic, operations shall be confined to one-half the roadway width at a time. The Contractor shall provide proper traffic control so that vehicles may proceed without damage to the treated area. Work shall not be started on the portion of the road not covered by previous application until the surface previously covered has dried and is ready for paving.

Traffic shall be kept off the tack coat at all times. The tack coat shall be sprayed only so far in advance of the surface course as will permit it to dry to a "tacky" condition. The Contractor shall maintain the tack coat until the next course has been placed. Any area that has become fouled, by traffic or otherwise, shall be cleaned by Contractor at his own cost before the next course is applied.

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SP-12-4 MEASUREMENT AND PAYMENT

The quantities of liquid asphalt, measured as stated above shall be paid for at the contract unit price per unit of Area, which payment shall be full compensation for furnishing fall labour, material, tools equipment and incidentals and for performing all the work involved in applying Tack coat, complete in place, as shown on the drawings and in accordance with these specifications:

Pay Item No. Description Measurement

SP2 (a) Cut-back Asphalt for Bituminous tack coat M2

SP2 (b) Emulsified Asphalt for Bituminous prime coat M2

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ITEM SP3 BITUMINOUS SURFACE TREATMENT AND SEAL COAT SP-13-1 DESCRIPTION

This work shall consist of one or more applications of asphaltic material and one or more covers of aggregate or an application of asphaltic material without aggregate applied in accordance with these specifications to the width shown on the typical cross sections or as directed by the Engineer.

SP-13-2 MATERIAL REQUIREMENT

SP-13-2.1 Aggregate

Aggregate shall consist of clean, dry, hard, tough, angular, sound crushed stone, or crushed gravel of uniform quality free from dust, clay and other deleterious materials and from excess of flat or laminated pieces. All aggregate materials shall have a percentage of wear by the Los Angeles Abrasion test (AASHTO - 96) of not more than 40 percent.

The portion of aggregate retained on the 1Cm (3/8inch) sieve shall not contain more than 15 percent of particles by weight so flat or elongated, or both, that the ratio between the maximum and the minimum dimensions exceeds 5:1.

The percentage composition by weight of aggregate shall conform to the following gradations:-

Us Standard Sieve Percentage passing by Weight

Size No.1 Size No.2 Size No.325 mm (1") 100 -

-19 mm (3/4") 90 – 100 -

-13 mm (1/2") 20 – 55 100 -09 mm (3/8") 0 – 15 85 –

100 10006 mm (1/4") - -

90 – 100 No.4 0 – 5

10 – 30 60 – 85 No.8 - 0 - 10

0 – 25 No.16 - 0 - 5

0 – 5 No.200 - 0 - 2

0 – 2

SP-14-2.2 Asphaltic Material

The asphaltic material shall conform to the requirements of Item SP-2-2 Asphaltic Materials. The type shall be one of the following as ordered by the Engineer.

Single Surface Treatment AC 80-100, RC-250,RC-70, RS-1 or RS-2

Double Surface Treatment : AC 80-100, RC-250,

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RS-1 or RS-2

Triple Surface Treatment : AC-80-100, RC-250,RS-1 or RS-2

Seal Coat : RC-250, RS-1 or RS-2

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SP-14-3 CONSTRUCTION REQUIREMENTS

At the time of the application, the weather shall be warm and dry, and the road surface shall be clean and dry. Spraying shall not be done unless the road temperature has been above 20oC (68oF) during the spraying. Prior to applying the asphaltic material, dirt and other objectionable materials shall be removed from the surface. If so directed by the Engineer, the surface shall be cleaned by power brooming until all loose and foreign materials are removed.

SP-14-3.1 Equipment

Equipment shall conform in all respects to the provisions under clause SP-9-3.1.

SP-14-3.2 Application of Asphaltic material

Asphalt cement, liquid asphaltic and emulsified asphalt shall be applied by means of pressure distributor at the temperature specified for the type and grade of asphalt being used. The rates of application shall be within the ranges given in table at page SP-15, however, the exact rate shall be determined by the Engineer.

The spread of BITUMINOUS materials shall not be more than 15 cm (6 inches) winder than the width covered by the aggregate from the spreading device.

SP-15-3.3 Spreading of Aggregate

Immediately after applying the asphaltic material, dry aggregate shall be uniformly and evenly distributed over the treated surface from an approved mechanical aggregate spreader. The truck carrying the aggregate shall move backward as it spread same so as to prevent the tyres of the truck and the mechanical aggregate spreader from driving directly on the newly sprayed asphalt. No portion of the binder shall remain uncovered for a period in excess of 20 minutes after spraying.

Immediately after spreading of the aggregate, the treated surface shall be rolled with a steel wheeled roller weight in 6 to 8 ton. A self propelled Pneumatic tyred roller having minimum contact pressure of 2.80 Kg/cm2 (40 lbs/in2) may be used as a second roller. Rolling shall continue only until a smooth, thoroughly compacted surface is obtained.

Any place where binder shows on the surface, shall be covered with additional aggregate and further rolled and broom-dragged until an even surface result, and does not adhere to wheels of vehicles.

The quantity of aggregates to be applied shall be within the ranges specified in table at page SP-15, however, the exact rate shall be determined by the Engineer.

SP-15-4 SHOULDER TREATMENT

SP-15-4.1 Earthen Shoulders

For earthen shoulders the material and construction shall conform to all requirements of embankment materials specified in section-E.

SP-15-4.2 Gravel Shoulders

For gravel shoulders the materials and construction requirements shall conform to all requirements of Section-SB.

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SP-16-4.3 Bituminous Treated Shoulders

The bituminous treatment of shoulders shall be a seal cost with cover material as specified in the clause SP or a seal coat without any aggregate cover if shown on the drawings or directed by the Engineer.

SP-16-5 Method of Measurement

Ist layer, 2nd layer or 3rd layer of bituminous surface treatment shall be measured by the units of Area for all areas shown on the plans or ordered by the Engineer to receive Ist or 2nd or 3rd layers of "Bituminous Surface Treatment". No measurement or payment will be made of areas "treated outside of the limits specified herein, shown on the plans or ordered by the Engineer. No measurement or payment will be made for materials used in excess of those specified by the Engineer nor shall they form the basis of a claim for additional payment.

Quantities of materials for Bituminous Surface Treatment

Surface Treatment Aggregate Bituminous Material Type Application Size

Quantity QuantityType

No. Kg/m2 Liters/m2

1.19 (a)Single Single 2

12.5 -----------------------------1.63 (b)

1.90 (a)

First 1 24.0----------------------------

2.14 (b)Double --------------------------------------------------

1.19 (a)Second 2 12.5

----------------------------1.63 (b)

1.90 (a)

First 1 24.0----------------------------

2.14 (b)Triple --------------------------------------------------

1.19 (a)Second 2 12.5

----------------------------1.63 (b)

--------------------------------------------------Third 3 6.5

0.68 (c)

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Seal Coat without 4 4

0.5 (c)

Aggregate

Note 1 i) Bituminous material types are (a) asphalt cement, (b) cut-back or emulsified

and (c) asphalt cement, cut-back and emulsified.

ii) Quantities of bituminous material may be varied by the Engineer by ± 15%

depending on site conditions.

iii) Prime coat shall be applied prior to the surface treatment for the newly constructed payment at the rate as specified in the Item 302.3.2.

SP-18-6 BASIS OF PAYMENT

The amount of completed and accepted work measured as provided above, will be paid for at the unit bid price per units of Area for the single surface treatment, double surface treatment or the triple surface treatment of "Bituminous surface treatment" in the bill of Quantities. The price shall be full compensation for furnishing all materials, all manipulation and maintenance, for furnishing all labour, equipment, tools, and all other items necessary for the proper completion of the work, including prime coat underneath.

Pay Item No. Description Measurement

SP3 (a) Bituminous Single Surface Treatment

M2

SP3 (b) Bituminous Double Surface Treatment 2nd Layer M2

SP3 (c) Bituminous Triple Surface Treatment M2

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ITEM SP4 ASPHALT CONCRETE PAVEMENT - PLANT MIX SP-19-1 DESCRIPTION

This work shall consist of furnishing and mixing aggregates and asphalt binder at a central mixing plant, transporting, spreading and compacting the mixture on a prepared base as Asphaltic Wearing Course in accordance with these specifications and to the lines, grades and typical pavement sections shown on the drawings or as directed by the Engineer.

SP-19-2 MATERIAL REQUIREMENTS

SP-19-2.1 Aggregates

Coarse and fine aggregates shall be clean, hard, tough sound particles free from decomposed material, vegetable matter and other deleterious substances.

Coarse aggregate which is material retained on the No.4 sieve, shall consist of crushed rock, crushed gravel or a mixture of natural and crushed gravel. Not less than 50 percent by weight of the coarse aggregate shall have at least one fractured face.

Fine aggregate, which is material passing the No.4 sieve, shall consist of gravel, sand, stone, screenings or a mixture thereof. Not less than 50 percent by weight of the fine aggregates shall be crushed particles.

The combined aggregate shall conform to one of the gradings shown in the following table:

Aggregate Grading Requirements

Use: A BC

Compacted Wearing, BinderWearing binder WearingThickness 2 in.min 1 1/2 in. min 1 in.min 50 mm Min 38 mm Min

25 mm Min

U.S Stan Percentage Passing by Weightdard Sieve

25mm (1") 100

-

-19mm (3/4") 80 –

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100100

-13mm (1/2") -

80 – 100

1009mm (3/8") 60 – 80

70 – 90

80 – 100No.4

48 – 65

50 – 70

55 – 75No.8

35 – 50

35 – 50

35 – 50No.30

19 – 30

18 – 29

18 – 29No.50

13 – 23

13 – 23

13 – 23No.100

7 – 15

8 – 16

8 – 16No.200

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1 – 8

4 – 10

4 – 10

When the combined grading of the coarse and fine aggregates is deficient in material passing the No.200 sieve, additional filler material shall be added. The filler material shall consist of finely divided rock dust, hydrated lime, hydraulic cement or other suitable mineral matter and shall conform to the following gradation:

Us Standard Sieve Percent Passing by Weight

No. 30 100No. 50 95 – 100 No.200 70 – 100

The coarse and fine aggregates shall meet the following requirements:

a) The percentage of wear by the Los Angles Abrasion test (AASHTO T-96) shall not be more than 40.

b) The loss when subject to five cyles of the Sodium Sulphate Soundness test (AASHTO T-104) shall be less than 12.

c) The sand Equivalent (AASHTO T-176) determined after all processing except for addition of asphalt cement shall not be less than 45.

d) All aggregates shall have a liquid limit of not more than 25 and a Plasticity Index of not more than 6 as determined by AASHTO T-89 and T-90, respectively.

e) The amount of thin and elongated pieces (Pieces larger than 25mm(1 inch) with thickness less than 1/5 of the length) by weight shall be less than 5 percent.

SP-21-2.2 Asphalt Material

Asphalt binder to be mixed with the aggregates to produce asphalt concrete shall be asphalt cement penetration grade 60-70 or 80-100 as specified by the Engineer.

SP-21-3 CONSTRUCTION REQUIREMENTS

SP-31-3.1 Equipment

The plant shall be either a batch plant or continuous mix plant of adequate capacity, coordinated and operated to produce a mixture within the limits of those specifications.

a) Scale - The plant scales for any weight box or hopper shall be either of the beam or springless dial type, sensitive to one-half of one percent of the maximum load that may be required and shall be a standard make and design. When of the beam type there shall be a separate beam with telltale indicator for each size of aggregate, and a tare beam for balancing the hopper.

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b) Equipment for storage and heating of asphalt cement - Tanks for storage of asphalt cement of a capacity of at least 3 days run shall be capable of heating the material, under effective and positive control at all times, to the temperature requirements set forth in table SP-1. The method of heating shall be such that the products of combustion or the flame shall not come into contact with the asphalt cement. Before the asphalt cement is placed in the mixer it shall be heated in a direct-fired heater of such capacity that it need never be less than half full. Heating of material supplied in barrels shall be subject to the same conditions.

c) Feeder for Dryer - The plant shall be provided with accurate mechanical means, for uniform feeding of the aggregates into the dryer so that a uniform production and a uniform temperature of the heated aggregates is secured.

d) Dryer - A rotary dryer of satisfactory design for drying and heating the aggregates shall be provided. The dryer shall be capable of drying and heating the aggregates to the temperature requirements pertaining to the type of asphaltic material specified in item SP-2-2 or/table SP-1.

e) Screens - Suitable screens capable of screening all aggregates to the sizes required, and having normal capacities slightly in excess of the maximum output of the mixing plant shall be provided.

f) Bins - The plant shall include storage bins for screened aggregates with total capacity of not less than three times the dead load of the mixer in the case of a batch mixer, or not less than a run of 10 minutes in the case of a continuous mixer. Bins shall be divided into compartments arranged to ensure separate and adequate storage of appropriate sizes of aggregate. Each compartment shall be provided with an overflow pipe that shall be of such a size and so located as to prevent any backing up of material into other bins. Adequate dry storage shall be provided for filler, if used, and satisfactory provision made for proportioning the filler for each batch of mixture.

g) Asphalt Cement Control Unit - Satisfactory means either by weighing, metering, or volumetric measurement, shall be provided to obtain the proper amount of asphalt cement, and all measuring devices shall be sensitive to a two percent tolerance of the amount required. Means shall be provided for checking the quantity or rate of flow of asphalt cement into the mixer. Suitable means shall also be provided, either by steam jacketing or other insulation, for maintaining the specified temperature of the asphalt cement in the pipe lines, meter, weigh buckets, spray bars and other containers of flow lines.

h) If an asphalt bucket is used for weighing the asphalt cement, it shall have sufficient capacity to hold not less than twenty percent of the weight of aggregate required for one batch. It shall be steam jacketed or equipped with properly insulated electric heating units and shall be suspended on dial scales equipped with a telltale device so that the tare weight can be accurately measured to a tolerance of two percent of weight required. The bucket shall be so arranged that it will deliver the heated asphalt cement in a thin uniform sheet or in multiple streams, the full width of the mixer where the asphalt cement will be sprayed into the mix.

i) Thermometer equipment - An armored thermometer to include the range from 90oC to 204oC or 200oF to 400oF shall be fixed in the asphalt cement feed line at a suitable location near the discharge valve at the mixer unit. The plant shall be further equipped with an approved dial scale mercury actuated thermometer, and

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electric pyrometer, or other approved thermometric instrument so placed at the discharge chute of the dryer so as to register automatically the temperature of the heated aggregate.

j) Control of Mixing Time - The plant shall be equipped with positive means to govern the time of mixer to the satisfaction of the Engineer. The time of mixing shall be considered as the interval between the time the asphalt cement is spread on the aggregate and the time the same aggregate is discharged from the mixer.

k) Dust Collector - When required by the Engineer or where dust interferes with the efficient operation of the plant, mixer cover, or a dust collecting system shall be installed. Provision shall be made to waste the material so collected, or to return it uniformly to the mixture as the Engineer may direct.

i) Safety Requirements - Adequate and safe stairways to the mixer platform and guarded ladders to other plant units shall be placed at all points requiring accessibility during plant operations. All gears, pulleys, chains, sprockets and other dangerous moving parts shall be adequately guarded and protected. Ample and unobstructed passage shall be provided on the mixing platform. A clear and unobstructed space shall be maintained at all times in and around the truck loading space, and this area shall be kept free from drippings from the mixing platform.

SP-24-3.2 Special Requirements for Batching Plants

a) Weight Box or Hopper - The equipment shall include means for accurately weighing each size of aggregates in a weigh box or hopper, suspended on scales, large enough in size to hold a full batch without hand raking or running over. The weight box or hopper shall be supported on a fulcrum and knife edges so constructed that they will not be easily thrown out of alignment or adjustment. Gates on both bins and hopper shall be so constructed as to prevent jeakage when they are closed.

b) Mixer Unit for batch Method - The Plant shall include a bath mixer of an approved twin pugmil type, rotary drum type, or other type that has proved itself capable of producing a uniform mixture within the limits of these specifications. It shall have a batch capacity of not less than 900 Kg (2000 lbs). If the pugmill type, the clearance of the blades from all fixed and moving parts shall not exceed 2 Cm (0.8 inch) If the mixing tank is not closed, it shall be fitted with a lid to prevent the dust from being dispersed into the air. The mixer shall be so constructed as to prevent leakage of contents. The mixer shall have an accurate time lock to control the operation of a complete mixing cycle by locking the weigh box gate after the charging of the mixer until the closing of the mixer gate at the completion of the cycle; it shall lock the asphalt bucket throughout the dry mixing period and shall lock the mixer gate through out the dry and wet mixing period. The dry mixing period is defined as the interval of the time between the opening of the weigh box gate and the application of asphalt cement, the wet mixing period is the interval of time between the application of asphalt cement and the opening of the mixer gate.

The control of the timing shall be adjustable and capable of being set at maximum intervals of 5 seconds for cycles of mixing up to 3 minutes. A mechanical batch counter shall be installed as a part of the timing devices and shall be so designed as to register only completely mixed batches.

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SP-25-3.3 Special Requirements for Continuous Mixing Plants

a) Gradation Control Unit - The Plant shall include a means for accurately proportioning each size of aggregate either by weighing by volumetric measurement.

When proportioning is by volume, the unit shall include a feeder mounted under the compartment bins. Each bin shall have an accurately controlled gate, for volumetrically measurement the material drawn from each respective bin. The gate shall be rectangular of dimensions of about 30x25 Cm (12 x 10 inches) with one dimension adjustable by positive mechanical means provided with a lock. Indicator shall be provided on each gate to show the gate opening in inches. Filler, if used shall be proportioned separately from a small hopper mounted directly over the mixer.

b) Weight Calibration of Aggregate Feed - The provide for calibration of Gate opening by means of weight test samples. The materials fed out of the storage bins through their individual orifices shall be by-passed to a suitable test box each compartment of material being confined in a separate box each compartment of material being confined in a separate box section. The plant shall be equipped to handle conveniently samples of about 360Kg (800 lbs) to be weighed on accurate scales.

c) Synchronization of Aggregate and Asphalt Feed - Means shall be provided to afford positive interlocking control between the flow of aggregate from the bins and the flow of asphalt cement from the meter or other proportioning sources to the satisfaction of the Engineer.

d) Mixer Unit for continuous Mixing - The plant shall include a continuous mixer of an approved type. The paddles shall be of an adjustable type for angular position on the shafts and shall be reversible to retard the flow of the mix. The mixer shall carry a manufacturer's plate giving the net volumetric contents of the mixer at the several levels derived from the aggregate per minute being fed at plant operating speed.

Determination of mixing time shall be by weight method, using the following formulas:

SP-26-3.4 Preparation of Aggregates

Before being fed to the dryer, aggregates for binder and wearing courses shall be separated into two or more size and stored separately. One storage unit shall contain aggregate of such size that 80 percent will pass Sieve No.4 and the other unit shall contain aggregate of such size that 80 percent will be retained on Sieve No.4. Should the Contractor elect to use natural fine material, a separate storage unit for such material shall be provided in addition to the two units mentioned above in this paragraph. If filler is used as a separate component it also will be stored and measured separately and accurately before being fed into the mixer.

In placing the materials in storage or in moving them from storage to the mixer any method which causes segregation of uncontrolled combination of materials of different

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grading shall be discontinued and the segregated or degraded materials shall be rescreened or wasted, and, if necessary, passed through the dryer before being mixed.

Fine and coarse aggregates shall be fed into the dryer at a uniform rate and the rate of feed shall be maintained within 10 percent of the amount set. Coarse and fine aggregates shall be dried and heated so that when delivered to the mixer they shall not be more than at a temperature of 15oC (59oF) above the mixing temperature for the asphalt cement being used, or as directed by the Engineer.

SP-26-3.5 Job-Mix-Formula

The Engineer will determine together with the contractor a job Mix Formula for the asphalt concrete mixture, established among the other things on basis of Marshall Tests made with the specified aggregates and asphalt cement to be used. Modifications of the mix must only be made with the approval of the Engineer.

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SP-26-3.6 Preparation and composition of the Mixture

When the mixture is prepared in a twin pug mixer, the volume of aggregate shall not be so great as to extend above the tips of the mixer blades, when these blades are in a vertical position. After the aggregate, including filler, has been loaded into the mixer, the asphalt cement shall be introduced and mixing shall continue until all particles of aggregate are coated uniformly.

The components shall be combined as to produce a mixture conforming to the following composition by weight.

Binder Coarse Percentage

Total aggregate (including filler) 96 – 95Asphalt Cement 4 – 5

Wearing Coarse Percentage

Total aggregate (including filler) 95 – 94Asphalt Cement 5 – 6

but the exact percentage of asphalt cement in the mix shall be based on the Job Mix Formula.

The combined grading of the aggregate including filler within the general grading limits specified shall be of such uniformity that the amount of materials passing the ASTM sieves during any one day's run will not vary more than the following percentage from the Job Mix approved by the Engineer on the basis of Marshall Tests made on samples taken from the asphalt plant during operation.

U.S. Standard Permissible variation bySieve weight of total mix,

percent by weight

No.4 and large ± 6%

No.8 ± 4%

No.30 ± 3%

No.200 ± 2%

Asphalt ± 0.2%

SP-28-3.7 Transportation of Plant-Mixture

The mixture shall be transported to the site in steel-plat lined truck with a minimum capacity of 5 tons. The inside of the body shall be lightly coated with a soap or detergent solution to prevent adherence of the mixture and shall be equipped with covers or tarpaulin to protect the mixture, which shall be used when directed by the Engineer.

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SP-28-3.8 Spreading and Compacting

All mixtures shall be dumped in spreader at a temperature of not less than 140oC (284oF) and all initial rolling shall be performed when the temperature of the mixture is such that performed when the temperature of the mixture is such that the sum of the air temperature plus the temperature of the mixture is between 150oC (300oF) and 190oC (375oF), the mixture shall not be placed on any wet surface or when weather conditions will otherwise prevent its proper handling or finishing.

Asphalt pavers shall be self-propelled mechanical spreading and finishing equipment, provided with a screed or strike off assembly capable of distributing the material to not less than the full width of a traffic lane. Screed action shall include any cutting, crowding or other practical action which is affective on the mixture without tearing, shoving or gouging, and which produces a surface texture of uniform appearance. The screed shall be adjustable to the required section and thickness. The paver shall be provided with either a full width roller or temper or other suitable compacting devices. Pavers that leave ridges, indentations or other marks in the surface that cannot be eliminated by rolling or prevented by adjustment in operation shall not be used.

The asphalt paving machine shall be equipped with automatic systems to control the screed for both longitudinal grade and cross slope. The automatic system may be purchased in kit form and locally installed or be a factory installed item. The control system may be a pneumatic-hydraulic or electric-hydraulic type actuated by grade sensors for the levelling course and/or simple make-break electrical switches type actuated by joint-matching shoes or ski-type devices for the binder and surface courses.

At points along the side of the stretch to be paved markers will be fixed so that the minor irregularities in the surface of the base course are not repeated in the asphaltic surface course.

Where a course previously laid is joined to a course to be laid later the first course shall be cut back and painted with asphalt cement as directed by the Engineer.

Before placement of an asphalt overlay on an existing pavement a levelling course should be applied if necessary to produce a surface with cross-fall 2.5% and the same tolerances as required for normal base. The longitudinal grade shall be satisfactory to the Engineer.

Before placement of every single layer of asphalt concrete whether it is a layer of levelling course, binder course or wearing course, a prime coat or a tack coat shall be applied to the surface to be overlaid.

The mix shall be compacted immediately after placing, initial rolling with a tandem steel roller or a three wheeled steel roller shall follow the paver as closely as possible. Immediately following the sealing of the longitudinal joints, rolling shall commence at the outside edges and progress towards the centre line. Intermediate rolling with a pneumatic tyred roller shall be done immediately behind the initial rolling. Final rolling shall eliminate marks from previous rolling. In areas too small for the roller, a vibrating plate compactor or hand tamper shall be used to achieve thorough compaction.

Rolling shall continue as long as required to attain a minimum compaction of 96 percent of the Marshall density of the approved Job Mix.

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SP-29-3.9 Requirement to the Mixture

When tested according to the Marshall Method, AASHTO T-245, the bituminous mixture shall conform to the following requirements:

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Binder Course Wearing Courses

No. of blows at each end of specimen 75 75

StabilityFlow, 8 – 16 8 – 16

Voids in total Mix. Percent 4 – 8 4.5 – 5.5

Aggregates voids filled with Asphalt Cement percent 60 – 70 65 – 75

The loss in Marshall stability by submerging specimens in water at 60oC(140oF) for 24 hours as compared to the stability measured after submerging in water at 60oC (140oF) of 20 minutes shall be 25 percent maximum.

The density in place shall be tested by cores taken from the various courses. The cores will be used to test the density by either Method A or B AASHTO Method of Test T-166, "Bulk Specific Gravity of Compacted Bituminous Mixture" which ever is applicable.

SP-30-3.10 Pavement Thickness and Tolerances

The asphalt concrete binder and wearing course shall be compacted to the desired level and cross slops as shown on the drawings or as directed by the Engineer.

The tolerances in compacted thickness in binder and wearing course shall be ± 10% from the desired thickness shown on the drawings or required by the Engineer. For determination of the average thickness. 10 cores per mile shall be taken as directed by the Engineer. If the average thickness so determined is deficient by more than + 10%, the engineer shall decide whether to accept to deficit thickness or to direct reconstruction.

The allowable tolerances for the finished surface of the wearing course shall be:

- Level 5 mm (0.2 in).

- 3 m (10 feet) straight edge5 mm (0.2 in).

- Cross fall (camber) ± 0.2 %

SP-31-4 MEASUREMENT AND PAYMENT

The quantities of asphalt concrete wearing course shall be measured by area and the thickness shall be as specified on drawings.

Quantities of liquid asphalt, wasted or remaining in hand after completion of the work, shall not be measured or paid for.

The quantities determined as provided above shall be paid for at the contract unit price of the particular pay item as shown in the Bill of Quantities, which prices and payment shall

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constitute full compensation for all the costs necessary for the proper completion of the work prescribed in this item.Pay Item No. Description Measurement

SP4 (a) A.C. Wearing course using mixture for mixing

M3 or M. Ton

SP4 (b) A.C. Wearing course using Central Mixing Plant.

M3 or M. Ton

SP-31-5 QUALITY CONTROL

The quality control tests and their frequency are given in tables at page Q.C.Tests.

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ITEM SPA-1 ASPHALTIC BASE COURSE PLANT MIX SPA1-1 DESCRIPTION

This work shall consist of furnishing of plant, labour, equipment and material and performing all operations in connection with the construction of an asphaltic plant-mix base course on a previously constructed and accepted subgrade, subbase or base complete, subject to teams and conditions of the Contract, and in strict accordance with this Section of the Specification, the Drawings and the directions of the Engineer.

SPA-2 MATERIAL REQUIREMENTS

Mineral Aggregate

Mineral aggregate for bituminous base course shall consist of coarse aggregate, fine aggregate and filler material, if required, all conforming with the following requirements.

Coarse aggregate which is the material retained on AASHTO No.4 selve shall consist of crushed rock, crushed gravel, crushed boulder. it shall be clean, hard, tough, sound durable, free from decomposed stones, organic matter, shale, clay lump or other deleterious substances. Rock or boulders from which coarse aggregate shall be obtained, must be of uniform quality throughout the quarry.

The amount of crushing shall be regulated so that at least Ninety (90) percent by weight of material retained on AASHTO No. 4 sieve shall consist of places with at least two (2) mechanically fractured faces, and when tested for stability of bituminous mix show satisfactory stability.

Fine aggregate which is material passing No. 4 sieve, shall consist of 100% crushed material from rock or boulder. No natural sand will be allowed in the mix.

When the combined grading of the coarse and fine aggregates is deficient in material passing No. 200 sieve, additional filler material shall be added. The filler material shall consist of finely divided rock dust, hydrated time, hydraulic cement or other suitable mineral matter. At the time of use, it shall sufficiently dry to flow freely and free from, congiomerations. Filler material shall conform to following gradation:

US Standard Sieve Percent Passing by Weight

No. 30 100No. 50 95 – 100 No. 200 70 – 100

The coarse and fine aggregates shall meet the following applicable requirements:

a) The percentage of water by the Los Angeles Abrasion Test (AASHTO T 96) shall not be more than forty (40).

b) The loss when subject to five cycles of the Sodium Sulphate Soundness Test (AASHTO 104) shall be less than twelve (12).

c) The Sand Equivalent (AASHTO T176) determined after all processing except for addition of asphalt cement shall not be less than forty five (45).

d) Fine aggregates shall have a liquid limit not more than twenty five (25) and a Plasticity Index of not more than six (6) as determined by AASHTO T 89 and T 90.

e) The portion of aggregate retained on the 9.5mm (3/8 inch) sieve shall not contain more than 15 percent by weight of flat and/or elongated particles (ratio of maximum to minimum dimensions = 5.1).

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SPA-2-2.2 Asphaltic Material

Asphaltic binder to be mixed with the aggretate to produce asphaltic base shall be asphalt cement having penetration grade 40-50, or 60-70 as approved by the Engineer. Generally it will meet the requirement of AASHTO M-20.

SPA-2-2.3 Asphalt Concrete Base Course Mixture

The composition of the asphaltic concrete paving mixture for base course shall conform to Class A and/or Class B shown in the following table:

TABLE 203-1

Combined Aggregate Grading Requirements

Mix Designation Class A Class BUse Levelling/Base Levelling/Base

Compacted Thickness 75-100 mm 50-100mm

U.S Standard Sieve Size Percent Passing by WeightClass A Class B

2" (50mm) 100

1½" (38 mm) 90-100 100

1" (25 mm) - 75-90

3/4" (19 mm) 56-75 65-80

1/2" (12.5 mm) - 55-70

3/8" (9.5 mm) - 45-60

No. 4 (4.75 mm) 23-40 30-45

No. 8 (2.38 mm) 15-30 15-35

No. 50 (0.300 mm) 4-10 5-15

No. 200 (0.75 mm) 3-6 2-7

Asphalt Concrete Weight 3 3percent of total mix (Minimum) (Minimum)

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The asphalt concrete levelling/base course mixture shall meet the following Marshall Test Criteria:

Compaction, number of belows each end of speciman 75

Stability 1200 Kg (Min.)

Flow 0.25 mm (0.01 in.) 8-14

Percent air volds in mix 5-9

Percent voids filled with bitumen 55-65

Percent voids in mineral aggregates 13 (Min)

Loss in Stability 25% (Max)

SPA-4-2.4 Job-Mix Formula

At least one (1) week prior to production, a Job-mix Formula (JMF) for the asphaltic base course to be used for the project, shall be established jointly by the Engineer and the Contractor in the project laboratory. Job mix formula shall combine the mineral aggregates and asphalts in such proportion conforming to specification requirements.

The JMF shall be established by MARSHALL Method of Mix Design according to the procedure prescribed in the Asphalt Institute Manual Series No. 2 9ms-20, May 1984 Edition or the latest Edition.

The JMF with the allowable tolerances shall be within the range specified in item 203.2.3. Each JMF shall indicate a single percentage aggregate passing each required sieve size and a single percentage of bitumen to be added to the aggregate.

After the JMF is established, all mixtures furnished for the project represented by samples taken from the asphalt plant during operation, shall conform thereto with the following ranges of tolerances:

Upon receiving the job-mix, approved by the Engineer, the Contractor shall adjust his planbt to proportion the individual aggregates, mineral filler and asphalt to produce a final mix that, when compared to job mix formula shall be within the following limit.

Maximum Variation of Percentage of Materials.

Passing No. 4 and larger sieves ± 7.0%

Passing No. 8 to No. 100 sieve ± 4.0%

Passing No. 200 ± 2.0%

Asphalt Content

Weight (percent of total mix) ± 0.3%

In addition to meeting the requirements specified in the preceding items the mixture as established by the JMF shall also satisfy the following physical proporty:

Loss of Marshall stability by immersion of specimen in water at sixty (60) degree centigrade for 24 hours as compared with stability measured after immersion in water at 60 degrees centigrade for 20 minutes shall not exceeds twenty five (25) percent. If the mixture fails to meet this criterion, JMF shall be modified or an antistripping agent shall

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be used.

Should a change of sources of materials be made, a new Job Mix Formula shall be established before the new material is used. When unsatisfactory results or other conditions make it necessary, a new Job Mix Formula will be required.

SPA-5-2.5 Asphalt Additives:

Cellulose Fibers shall be used as an asphalt additive with the aim of eliminating bleeding tendencies at the rate of 0.2 to 0.25 percent by weight of the total mix. Additives shall be fed by a separate feeding system or manually into pugmill for each batch. The weight of the additive shall be determined in accordance with the percentage specified in the Job mix formula.

SPA-5-3 CONSTRUCTION REQUIREMENTS

SPA-5-3.1 Bituminous Mixing Plant.

Plants used for the preparation of bituminous mixtures shall be "Batching Plants" conforming to AASHTO M 156, and of adequate capacity, coordinated and operated to produce a mixture within the limits of these specifications.

SPA-5-3.2 Preparation of Aggregates

Before being fed to the dryer, aggregates for the asphaltic base course shall be separated into two or more sizes and stored separately in cold bins. One bin shall contain aggregate of such size that eighty (80) percent will pass sieve No.4, and the other bin shall contain aggregate of such size that eighty (80) percent will be retained on sieve No.4. Should fine material, be in corporated in the mix, separate bin shall porovided in addition to the two bins mentioned above. If filler is used as a separate component it will also be stored and measured separately and accurately before being fed into the mixer.

Asphalt cement shall be heated within a temperature range of hundred and thrity five to hundred and sixty three (135-163) degreed centigrade at the time of mixing. All material reheated more than forty two (42) degrees centigrade above maximum shown shall be considered overheated and shall be rejected until material is sampled and tested.

Dried aggregate weighted and drawn to pugmill shall be combined with proportionate amount of asphalt cement according to the job mix formula. Temperature of asphalt, except for temporary fluctuations, shall not be lower than fifteen (15) degrees centigrade below the temperature of the aggregate, at the time, the two (2) materials enter into the pugmill.

In placing the materials in bins or in moving them from bins to the mixer, any method which causes segregation or uncontrolled combination of

materials or different grading, shall be discontinued and the segregated or degraded materials shall be rescreened, or washed, and, if necessary passed through the dryer before being mixed.

Each aggregate ingredient shall be heated and dried at temperature not to exceed hundred and sixty three (163) degrees centigrade. If aggregate contain sufficient moisture to cause foaming in the mixture or their temperature is in excess of hundred and sixty three (163) degrees centigrade, they shall be removed from the bins and returned to their respective stock piles. In no case, shall be temperature of asphaltic mix exceed 153 degree centigrade when discharged from the pugmill.

Immediately after heating, the aggregates shall be screened to required sizes and stored in seperate bins for batchig and mixing with bituminous material.

SPA-6-3.3 Hauling Equipment

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Dump truck used for hauling bituminous mixtures shall have tight, clean, smooth metal beds which have been thinly coated with an approved material to prevent adhering of material to the beds. Each truck shall have a cover of canvas or of other suitable material of sufficient size as to protect the mixture from the weather. The mixtuer will be delived on the road at a temperature not less than hundred & thrity (130) degree C.

SPA-6-3.4 Bituminous Pavers

Bituminous pavers shall be self-contained, power-propelled units, provided with an automatically controlled activated screed or strike-off assembly, heated if necessary, capable of spreading and finishing courses of bituminous plant mix material in lane widths applicable to the specified typical section and thicknesses shown on the plans. Pavers used for shoulders and similar construction shall be capable of spreading and finishing course of bituminous plant mix material in widths shown on the plans.

The paver shall be equipped with a receiving hopper having sufficient capacity for a uniform spreading operation. The paver shall be equipped with automatic feed controls, properly adjusted to maintain a uniform depth of material ahead of the screed.

The screed or strike-off assembly shall be capable of producing a finished surface of the required evenness and texture without tearing, shoving or gouging the mixture.

When laying the mixtures, the paver shall be capable of being operated at forward speeds consistent with satisfactory laying of the mixtuer. The paver shall be operated at speeds which will give the best result for the type of power being used.

The mixed material shall be delivered to power in time to permit completion of spreading, finishing and compaction of mixture during day light hours.

The paver shall be equipped with automatic screed controls with sensors for either or both sides of the paver, capable of sensing grade from an outside reference line, sensing the transverse slope of the screed and providing the automatic signals which operates the screed to maintain the desired grade and transverse slope. The sensor shall be so constructed that it will operate from a reference line or a ski-like arrangement.

The transverse slope controller shall be capable of maintaining the screed at the desired slope within plus or minus 0.1 percen tvariation.

Manual operation will be permitted in the construciton of irregularly shaped and minor areas.

Whenever a breakdown or malfunction of the automatic controls occurs, the equipment may be operated manually or by other methods in order ot allow the contractor to use the asphalt already produced at the plant or transit, provided this method of operation will produce results otherwise meeting the speciffications.

Reference lines will be required for both outer edges of the travelled way for each main line roadway for vertical control. Horizontal control utilizing the referenc line will be permitted. The grade and slope for intermediate lane sshall be controled automatically from reference lines or by means of a ski and a slope control device or a dual ski arrangement. When the finish of the grade prepared for paving is superior to the established tolerance and, when in the opinion of the Engineer, further improvement to the line, grade, cross sections and smoothness can best be achieved without the use of the reference line, a ski-liike arrangement may besubstituted subject to the approval of the Engineer. The use of the reference lines shall be reinstated immediately whenever the Contractor fails to maintain a superior pavement. The contractor shall furnish and install all pins, brackets, tensioning devices, wire and accessories necessary for satisfactory operation of the automatic control equipment.

SPA-7-3.5 Rollers

Rollers shall be steel wheel, pneumatic tyre or vibratory, or combination thereof. The

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roller(s) shall be in good condition, capable of reversing without backiash, and shall be operated at speeds show enough to avoid displacement to the bituminous mixture. The number and weight of rollers shall be sufficient to compact the mixture to the required density while it is still in a workable condition. Vibratory rollers shall be acceptable for bituminous mixture compaction. The use of equipment which results in exceesive crusing of the aggregate will not be permitted.

SPA-8-3.6 Preparation of Base of Existing Pavement Surface

Before spreading materials the surface of base or existing pavement on which the mix is to be placed shall be conditioned by application of a prime or tack coat as specified.

After a prime coat is applied, it shall be left undisturbed not less than twenty four (24) hours. The contractor shall maintain the primed surface until the mix material has been placed. This maintenance shall include the spreading of san dor other approved material, if necessary to prevent adherence of the prime coat to the tyres of vehicles using the primed surface, and patching any breaks in the primed surface with additional bituminous material or any area of primed surface with additional bituminous material. Any area of primed surface that has become damaged shall be repaired before the mix is placed.

After a tack coat is applied, it shall be allowed to dry until it is in the proper condition of tackiness to receive the mix. The tack coat shall be applied only as far in advance of the placing of mix, as is necessary to obtain the proper condition of tackiness. Any breaks in the tack coat shall be repaired.

When the surface of the existing pavement or old base is irregular, it shall be brought to unifrom grade and cross-section by levelling course as directed. The levelling course mixture shall conform to the requirements of item 203.2.

A thin coating of bituminous material shall be placed on contact surface of curbing, gutters, manholes and other structures prior to the bituminous mixture being placed against them.

SPA-8-3.7 Spreading and Finishing

The mixture shall be laid upon an approved surface, spread and struck off to the section and elevation established. Bituminous pavers shall be used to distribute the mixture either over the entire width or over such partial width as may be practicable.

The longitudinal joint in one layre shall offset to that in the layre immediately below, by approximately 15.0cm: however, the joint in the topy layer shall be at the centerline of the pavement if the roadway comprises two lanes of width, or at lane lines if the roadway is more than 2 lanes in width.

On areas which irregularities or unavoidable obstacles make the use of mechanical spreading and finishing equipment impracticable, the mixture shall be spread, raked and luted by hand tools. For such areas the mixture shall be dumped, spread and screeded to give the required compacted thickness.

When production of the mixture can maintained and when practical, pavers shall be used in echelon to place the wearing course in adjacent lanes and shoulders.

All mixtures shall be spread at a temperature of not less than hundred and thirty (130) degree C and all initial rolloing or tamping shall be performed when the temperature of the mixture is such that the sum of the air temperature plus the temperature of the mixture is between 165 degree C and 190 degree C. The mixture shall not be placed on any wet surface or when weather conditions will otherwise prevent its proper handling or finishing.

SPA-9-3.8 Compaction

After spreading and strike off and as soon as the mix condition permits the rolling to be

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performed without excessive shoving or tearing, the mixture shall be thoroughly and uniformly compacted. Rolling shall not be prolonged when cracks appear on the surface.

Initial or breakdown rolling shall be done by means of either a tandem steel roller or three wheeled steel roller. Rolling shall begin as soon as the mixture will bear the roll without undue displacement.

The number, and weight of rollers shall be sufficient to obtain the required compaction while the mixture is still in workable condition. The sequence of rolling and the selection of roller types shall provide the specified pavement density. Initial rolling with a tandem steel roller or a three-wheeled steel roller shall follow the paver as closely as possible.

Unless otherwise directed, rolling shall begin at the lower side and proceed longitudinally, parallel to the road centerline, each trip overlapping one-half of the roller width, gradually progressing to the crown of the road. When paving in echelon or abutting a previously placed lane, the longitudinal joint should be rolled first followed by the regular rolling procedure. On super elevated curves the rolling shall begin at the low side and progress to the high side by overlappong of longitudinal trips parallel to the centerline. Intermediate rolling with a pneumatic tyred roller shall be done behind the initial rolling. Final rolling shall eliminate marks from previous rolling. In no case shall the temperature be less than hundred & twenty (120) degree C, for initial break down rolling while all other compaction operations shall be completed before the temperature drops down to hundred & ten (110) degree C.Rollers shall move at a slow but uniform speed with the drive roll or wheels nearest the paver. Rolling shall, be continued until all roller marks are elimitated and a minimum density of Ninety seven (97) percent of a laboratory compacted specimen made from asphaltic material obtained for daily marshall density.

Any displacement resulting while reversing of the direction of a roller, or from other causes, shall be corrected at once by the use of rakes and addition of fresh mixture when required. Care shall be exercised in rolling not to displace the line and grade of the edges of the bituminous mixture.

To prevent adhesion of the mixture to the rollers, wheels of rollers shall be kept properly moistened with water or water mixed with very small quantities, of detergent or other approved material. Excess liquid will not be permitted.

Along forms, curbs, headers, walls and other places not accessible to the roller, the mixture shall be thoroughly compacted with hot hand tampers, smoothing irons or with mechanical tampers. On depressed areas, a tempers be used or clealed compression strips may be used under the roller to transmit compression to the depressed area.

Any mixture that become loose and broken, mixed with dirt, or is in any way defective in finish or density shall be removed and replaced with fresh hot mixture, which shall be compacted to conform with the surrounding area. Any area showing an excess or deficiency or bituminous material shall be removed and replaced.

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SPA-10-3.9 FREQUENCY OF TESTING FOR CORES

Core shall be taken for each seven hundred fifty (750) square meters of base, or fraction thereof, in special cases. If the core so taken is failed against the specified density, then two (2) additional cores shall be taken in the longtiudinal alignment of the road at an interval of three (3) meters on eithe rside with respect to the failing core and shall be tested against field density. If these core pass, then the individual compaction of the core shall not be less than Ninety three (93) percent and average of these three cores, in no case be less than Ninety five (95) percent. If average of the cores further fails against compaction, then retake the cores at a distance of fifteen (15) meters on either side and compaction shall be checked in the same fashion. In case of failure of the average of these five cores, the failed area shall be removed and subsequently be replaced by specified mix in an approved manner under the expense of contractor.

SPA-10-3.10 PAVEMENT THICKNESS AND TOLERANCES

After completion of final rolling, the finished surface shall be tested for smoothness with three (3) meters strength edge by Engineer at selected locations. The variation of surface from testing edge of straight edge between any two (2) contacts with the surface shall at no point exceeds six (6) millimeters when placed either parallel or perpendicular to centreline of roadway.

Any irregularities that exceed the specified tolerances or that retain water on the surface shall be corrected by removing the defective area and replacing with new base course without additional cost to the Employee.

For determination of the average thickness, six (6) cores per kilometer shall be taken or as directed by the Engineer. Unless otherwise permitted, cores extracted for thickness measurement shall not be used for density determination and density cores shall not be used for thickness measurements.

When layer thickness of asphaltic base course is deficient by more than five (5) mm from that specified in the Drawings, the deficiency shall be removed with satisfactory base course material and/or made upt by additional asphalt concrete wearing course thickness without extra cost to the Employee. If such remedial action is authorised, revised thickness determinations shall be made by measurements of new cores taken after placing of "Asphaltic Wearing Course" material or as directed by the Engineer. If base course deficiencies are corrected in this manner, full payment for the "Asphaltic Base Course" will be made to the Contractor, but not additional payment will be made for the increase in thickness of the "Asphaltic Wearing Course".

SPA-11-3.11 ACCEPTANCE SAMPLING AND TESTING

Acceptance for samples and testing of materials and construction requirements shall be governed by the relevant, "Table for Sampling and Testing Frequency" or as approved by the Engineer.

SPA-11-3.12 Weather Limitations

Hot asphaltic mixtures shall be placed only when the air temperature is four (4) degrees centigradeor above and no asphalt shall be laid under foggy or rainy weather or over moist surface.

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SPA-11-4 MEASUREMENT AND PAYMENT

SPA-11-4.1 Measurement

The quantities for asphaltic levelling/base course shall be measured by weight.

The quantity of asphalt concrete to be measured as a contract item shall be determined by weighing the completed mixture, acceptably placed in the work. For the purpose of measurement of asphalt premix, each truck leaving the asphalt plant will receive a load ticket specifying the type of asphalt premix and the weight of asphalt premix carried in the truck, certified by an inspector at asphalt p lant. Te premix in the truck shall become a payable item, when delivered at site and certified by a site inspector to be laid compacted and finished in an acceptable manner as mentioned above. The completed mixture hall be weighed on approved vehicle scales, whether portable or fixed which have been previously tested, certified by the Enginer. If the method of measurement other than mentioned above is adopted the same should be approved by the Engineer.

In order to overcome practical difficulty in compaction of asphalt concrete on edges, the Engineers and Contractor must agree on the Cross Section which will be used for payment before asphaltic compacting work start. Any asphalt laid beyond the agreed limits will not be paid.

The quantity of asphaltic material used is included in the asphalt concrete mixture and will not be measured separately.

Quantities of liquid asphalt, wasted or remaining on hand after completion of the work, shall not be measured or paid for.

SPA-12-4.2 Payment

The quantities determined as provided above shall be paid for at the contract unit price respectively for each of the particular pay items listed below and shown in the Bill of Quantities, which prices and payment shall consititute full compensation for all costs necessary for the proper completion of the work prescribed in this item:

Pay Item No. Description Measurement

SPA (a) Asphaltic Base Course Plant Mix (Class A) M. Ton or M3

SPA (b) Asphaltic Base Course Plant Mix (Class B) M. Ton or M3

SPA(c) Asphaltic Levelling Course Plant Mix (Class A)

M. Ton or M3

SPA (d) Asphaltic Levelling Course Plant Mix (Class B)

M. Ton or M3

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ITEM SPB ASPHALT CONCRETE WEARING COURSE - PLANT MIX SPB-1-1 DESCRIPTION

This work shall consist of furnishing aggregates and asphalt binder at a central mixing plant, to a specified temperatures transporting, spread and commenting the mixture in an approved, primed or tacked, base, subbase subgrade, bridge deck or concrete pavement in accordance with these specifications and in conformity with the lines, grades and typical cross-sections shown in the drawings or as directed by the Engineer.

SPB-1-2 MATERIAL REQUIREMENTS

SPB-1-2.1 Mineral Aggregates

The Aggregates shall consist of coarse aggregates, fine aggregates and filler material, if required and shall be clean based, tough, durable and sound particles of uniform quality and from decomposed material, vegetable matter shall clay, lumps and other deterious substances.

Course aggregate which is the material retained on an AASHTO No. 4 Sieve, shall consist of one hundred (100)% crushedrock or crushed gravel having two (2) faces mechanically crushed. The type of source shall be uniform throughout the quarry location from where such a material is obtained. The course aggregates shall be free from an excess of flat elongated prices.

Fine aggregate which is the material passing on AASHTO No. 4 sieve, shall consist of 100% crushed material from rock or boulder. Fine aggregate shall be stored separately, and no natural sand will be allowed in the mix.

When the combined grading of the coarse and fine aggregates in deficient in material passing the AASHTO No. 200 sieve, mineral filler material shall be added as approved by the Engineer. The filler shall consist of finely divided mineral matter such as rock dusts, hydrated lime, hydraulic cement or other suitable mineral matter free from lumps, balls or other deleterious material and shall confirm to the following gradation:

US Standard SievePercent Passing by

Weight

No. 30 (0.600mm) 100

No. 50 (0.300mm) 95-100

No. 200 (0.075mm) 70-100

The coarse and fine aggregates shall meet the following requirements:

a) The percent of wear by the Los Angeles Abrasion test (AASHTO T96) shall not be more than thirty (30).

b) The loss when subjected to five cycles of the Sodium Sulphate Soundness test (AASHTO T 104) shall be less than twelve (12).

c) The Sand Equivalent (AASHTO T 176) determined after all processing except for addition of asphalt cement shall not be less than 45.

d) All aggregates shall have a liquid limit of not more than twenty five (25) and a Plasticity Index of not more than four (4) as determined by AASHTO T-89 and T-90.

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e) The portion of aggregate retained on the 9.5mm (3/8 inch) sieve shall not contain more than 15 percent by weight of flat and/or elongated particles (ratio of maximum to minimum dimension = 5:1).

f) The three dimensions of particles shall be nearly equal. For atleast eighty (80) % of the particles, the proportion between the largest and smallest dimension shall be two and a half (2.5) or less and for atleast ninety five (950 % of the particles the same proportion shall be three (3) or less.

The percentage of particles having certain proportions between their largest and smallest dimensions (i.e. between the largest distance the particles can fill out between two parallel planes that will permit the particle to pass), shall be determined in the following way:

i. Forma a sample of course aggregates, all particles passing No. 4 sieve are eliminated. The sample shall be of sufficient quantity that atleast 100 particles remain.

ii. By means of a sliding callper, the largest and smallest dimensions, as defined above, are determined for each particle and its proportion calculated (with one decimal).

iii. The total weights of particles having the proportions two and a half (2.5) or less and three (3) or less, ae determined and their percentage in relation to the total sample are calculated.

SPB-2-2.2 Asphaltic Material

Asphaltic binder to be mixed with the aggregate to produce asphaltic base shall be asphalt cement penetration grade 40-50, or 60-70 as specified by the Engineer. Generally it will meet the requirement of AASHTO M-20.

SPB-2-2.3 Asphalt Concrete Wearing Course Mixture

The composition of the asphaltic concrete paving mixture for wearing course shall conform to Class A and/or Class B shown in the following table:

SPB-2

Asphalt Concrete Wearing Course Requirements

Mix Designation Class A Class B

Compacted Thickness 50-100mm 35-60

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Combined Aggregate Grading Requirements

US Standard Sieve Sizes Percent Passing by WeightClass A Class B

1" (25mm) 100 -

3/4" (19mm) 90 – 100 100

1/2" (12.5mm) - 75 – 90

3/8" (9.5mm) 56 – 70 60 – 80

No.4 (4.75mm) 35 – 50 40 – 60

No.8 (2.38mm) 23 – 35 20 – 40

No.50 (0.30mm) 5 – 12 5 – 15

No.200 (0.075mm) 2 – 8 3 – 8

Asphalt Content Weightpercent of total mix 3.5 (Min) 3.5 (Min)

The asphalt concrete wearing course mixture shall meet the following Marshal Test Criteria:

Compaction, number of blows each end of specimen 75

Stability 1000Kgm (Min)

Flow, 0.25mm (0.01 inch) 8-14

Percent air voids in mix 5-8

Percent voids filled with bitumen 65-75

Percent voids in mineral aggregates 14 (Min)

Loss of Stability 20 % (Max)

SPB-3-2.4 Job-Mix Formula

Atleast one week prior to production a Job-Mix Formula (JMF) for the asphaltic wearing course mixture or mixtures to be used for the project, shall be established jointly by the Engineer and the Contractor.

The JMF shall be established be Marshall Method of Mix Design according to the procedure prescribed in the Asphalt Institute Manual Series No. 2 (MS-20), May 1984

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Edition or the latest Edition.

The JMF, with the allowable tolerances, shall be within the master range specified in Table 305-1. Each JMF shall indicate a single percentage of aggregate passing each required sieve and a single percentage of bitumen to be added to the aggregates.

After the JMF is established, all mixtures furnished for the project represented by samples taken from the asphalt plant during operation, shall conform thereto with the following ranges of tolerances:

Combined Aggregates Gradation

Passing No.4 and Larger Sieves± 6.0 %

Passing No.8 to No.100 Sieves± 4.0 %

Passing No.2

± 2.0 %

Asphalt Content

Weight (percent of total mix)± 0.3 %

In addition to meeting the requirements specified in the preceeding items, the mixture as established by the JMF shall also satisfy the following physical property.

Loss of Marshall Stability by immersion of specimen in water at sixty (60) degree C, for twenty four (24) hours as compared with the stability measured after immersion in water at sixty (60) degree C, for twenty (20) minutes shall not exceed twenty (20) percent. If the mixture fails to meet this criterion, the JMF, shall be modified or an anti-stripping agent shall be used.

Should a change of sources of materials be made a new job Mix Formula shall be established before the new material is used. When unsatisfactory results or other conditions make it necessary, a new job Mix Formula will be required.

SPB-4-2.5 Asphalt Additives

Cellulose Fibres shall be used as an asphalt additive with the aim of eliminating bleeding tendencies. Normally 0.2 to 0.25% by weight of the total mix will be required. The fibres shall be fed into the pugmill by a separate feeder system or by hand into every batch. The weight of the fibres shall be determined in accordance with the percentage specified in the job-mix formula.

SPB-5-3 CONSTRUCTION REQUIREMENTS

Construction requirements for this item shall conform with the same as specified for Asphaltic Concrete Base Course Plant Mix under item SPA-5-3, except as modified in the following sub-items.

SPB-5-3.1 Preparation of Base Course Surface

Before spreading materials, the surface of the previously constructed and accepted base course on which the mix is to be placed shall be conditioned by application of a tack coat, if directed by the Engineer.

SPB-5-3.2 Payment Thickness and Tolerances

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The asphalt concrete wearing course shall be compacted to the desired level and cross slope as shown on the drawing or as directed by the Engineer.The tolerances in compacted thickness of the wearing course shall be ± five (5) percent from the desired thickness shown on the drawings. For determination of the average thickness, six (6) cores per kilometer shall be taken as specified in the Special Provisions or as directed by the Engineer. If the average thickness so determined is deficient by more than ± 5 percent, the Engineer shall decide whether to accept the deflicit thickness or to direct reconstruction.

The surface of the wearing course shall be tested by the Engineer using a 3 meter straightedge at selected locations. The variation of the surface from the testing edge of the straightedge between any two contacts, longitudinal or transverse with the surface shall at no point exceed five (5) millimeters. The cross fall (camber) shall be with ± 0.2 percent of that specified, and the level at any point shall be within ± 0.5 millimeters of the level shown on the Drawings. All humps or depressions exceeding the specified tolerance shall be corrected by removing the defective work and replacing it with new material, by overlying, or by other means satisfactory to the Engineer.

SPB-5-3.3 Acceptance Sampling and Testing

Acceptance of sampling and testing for this item with respect to materials and construction requirements, not specified herein, shall be in accordance with the relevant, " Tables for Sampling and Testing Frequency " in these specifications.

SPB-6-4 MEASUREMENT AND PAYMENT

SPB-6-4.1 Measurement

The quantities of asphaltic wearing course shall be measured by weight.

The quantity of asphalt concrete to be measured as a contract item shall be determined by weighing the completed mixture, acceptably placed in the work.

For the purpose of measurement of asphalt premix, each truck leaving the asphalt plant will receive a load ticket specifying the type of asphalt premix and the weight of asphalt premix carried in the truck, certified by an inspector at asphalt plant. The premix in the truck shall become a payable item when delivered at site and certified by a site inspector to be laid compacted mixture shall be weighed on approved vehicle scales, whether portable or fixed which have been previously tested, certified and sealed by the Engineer. Anyother method used for the measurement shall be approved by the Engineer.

In order to overcome practical difficulty in compaction of asphalt concrete on edges, the engineer and contractor must agree on the corss section which will be used for payment before asphaltic work start. Any asphalt laid beyond the agreed limits will not be paid.

A tolerance of ± five (5) mm shall be allowed in compacted thickness for each Asphalt concrete layer. However, any asphalt in excess of five (5) mm shall not be paid and any layer deficient by more than five (5) mm may be rejected unless rectified by overlaying additional layer at no extra cost, approved by the Engineer. This shall be applied on each two thousand (2000) SM area or each day's production whichever is less. Thickness of compacted asphalt concrete layer shall be determined by cutting cores by random Sampling Method.

The quantity of asphaltic material used is included in the asphalt concrete mixture and will not be measured separately.

Quantities Bitumen, wasted or remaining on hand after completion of the work, shall not be measured or paid for.

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SPB-6-4.2 Payment

The quantity determined as provided above shall be paid for at the contract unit price respectively for each of the particular pay items listed below and shown in the Bill of Quantities, which prices and payment shall constitute full compensation for all the costs necessary for the proper completion of the work prescribed in this item:

Pay Item No. Description Measurement

SPB (a) Asphaltic Concrete for Wearing Course (Class A)

M3 or M. Ton

SPB (b) Asphaltic Concrete for Wearing Course (Class B)

M3 or M. Ton

SPB(c) Asphaltic Additive

Kg or M3

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