32 12 11 - Bituminous Surface Treatments.doc

DIVISION 32 – EXTERIOR IMPROVEMENTS

SECTION 32 12 11

BITUMINOUS SURFACE TREATMENT

11/08

PART 1 GENERAL

This guide specification covers the requirements for single and double bituminous surface treatment of pavements for airfields, roads, streets, parking areas, and other general applications.

1.1 MEASUREMENT PROCEDURES

The bituminous material and aggregate to be paid for will be the measured quantities used in the accepted work.

1.1.1 Bituminous Material

The amount of bituminous material to be paid for will be measured in the number of gallons of material used in the accepted work, corrected to gallons at 60 degrees F in accordance with ASTM D 633 and ASTM D 1250 (using a coefficient of expansion of 0.00025 per degree F for asphalt emulsion).

1.1.2 Aggregate

The amount of aggregate paid for will be the number of cubic yards of aggregate placed and accepted in the completed work or placed in authorized stockpiles.

1.1.3 Quantity Limits

The bituminous material and aggregate shall be spread within the quantity limits shown in PART 2; bids shall be based on the mean of the values in the tables. The individual quantities of bituminous material and aggregate may be varied to meet specific field conditions at all times during progress of the work, as directed, without adjustments to contract unit prices.

1.2 PAYMENT PROCEDURES

The quantities of aggregates and bituminous material, determined as specified in paragraph MEASUREMENT FOR PAYMENT, will be paid for at the respective contract unit prices, which payment shall constitute full compensation for all operations necessary to complete the work as specified herein.

1.3 WAYBILLS AND DELIVERY TICKETS

Before the final statement is allowed, file with the Contracting Officer certified waybills and delivery tickets for aggregate and bituminous material used in the bituminous surface treatment. Do not remove bituminous material from the tank car or storage tank until initial outage and temperature measurements have been taken; nor shall the car or tank be released until final outage has been taken.

1.4 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM INTERNATIONAL (ASTM)

ASTM C 131 (2006)Standard Test Method for Resistance to Degradation of Small-Size Coarse

Aggregate by Abrasion and Impact in the

Los Angeles Machine ASTM C 136 (2006) Standard Test Method for Sieve

Analysis of Fine and Coarse Aggregates ASTM C 29/C 29M (2009) Standard Test Method for Bulk

Density ("Unit Weight") and Voids in

Aggregate ASTM C 88 (2005) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or

Magnesium Sulfate ASTM D 1139 (2009) Aggregate for Single or Multiple

Bituminous Surface Treatments ASTM D 1250 (2008) Standard Guide for Use of the

Petroleum Measurement Tables ASTM D 140/D 140M (2009) Standard Practice for Sampling

Bituminous Materials ASTM D 2028 (2010) Cutback Asphalt (Rapid-Curing Type) ASTM D 2397 (2005) Standard Specification for Cationic

Emulsified Asphalt ASTM D 3381 (2009a) Viscosity-Graded Asphalt Cement for Use in Pavement Construction ASTM D 3625 (1996; R 2005) Standard Practice for

Effect of Water on Bituminous-Coated

Aggregate Using Boiling Water ASTM D 633 (1997; R 2005) Volume Correction Table for

Road Tar ASTM D 75/D 75M (2009) Standard Practice for Sampling

Aggregates ASTM D 946 (2009a) Penetration-Graded Asphalt Cement for Use in Pavement Construction

ASTM D 977 (2005) Emulsified Asphalt

1.5 SYSTEM DESCRIPTION

Provide equipment dependable and adequate for the purpose intended and properly maintained in satisfactory and safe operating condition at all times. Discontinue the use of equipment which fails to produce satisfactory work and replace with satisfactory equipment. Calibrated equipment such as asphalt distributors, scales, batching equipment, spreaders and similar equipment, shall have been recalibrated by an approved calibration laboratory within 12 months prior to commencing work and every 12 months thereafter, by such laboratory from the date of recalibration, during the term of the contract.

1.5.1 Bituminous Distributors

The distributors shall have pneumatic tires of such width and number that the load produced on the base surface does not exceed 650 pounds per inch of tire width. Distributors shall be designed and equipped to distribute bituminous material uniformly at even heat on various widths of surface at readily determined and controlled rates ranging from 0.05 to 2.00 gallons/square yard, with a pressure range of 25 to 75 psi. The allowable variation from any specified rate shall not exceed 5 percent. Distributor equipment shall include a separate power unit for the bitumen pump, full-circulation spray bars, tachometer, pressure gauges, volume-measuring devices, a thermometer for reading the temperature of tank contents, and a hose attachment suitable for applying bituminous material to areas not accessible with distributor spray bar. The distributor shall be equipped for circulation and agitation of bituminous material during the heating process.

1.5.2 Single-Pass, Surface-Treatment Machines

The machines shall be capable of spraying bituminous material and spreading aggregate in one pass. Bituminous spraying equipment shall conform to the requirements given above for a bituminous distributor. The machine shall be capable of spreading aggregates at controlled amounts per square yard as specified. In addition, the single-pass, surface-treatment machine shall be capable of placing a surface treatment adjacent to an existing surface treatment, forming a joint of the same thickness and uniformity as other portions of the surface treatment. Ridges or blank spaces will not be permitted. Joints in the second application shall be formed at least 1 foot from those formed in the first application.

1.5.3 Heating Equipment for Storage Tanks

The equipment shall consist of coils and equipment for producing steam or hot oil and be designed to prevent the introduction of steam or hot oil into the material. An armored thermometer with a range of 100 to 400 degrees F shall be affixed to the tank so the temperature of the bituminous material may be determined at all times.

1.5.4 Power Rollers

Power rollers shall be steel-wheeled or pneumatic-tired type, conforming to the following requirements:

a. Steel-wheeled rollers shall have at least one steel drum and weigh a minimum of 5 tons. Steel wheels of the rollers shall be equipped with adjustable scrapers.

b. Pneumatic-tired rollers shall be self-propelled and have wheels mounted on two axles in such manner that the rear tires will not follow in the tracks of the forward group. Tires shall be uniformly inflated to not less than 60 psi nor more than 80 psi pressure. The pneumatic-tired rollers shall be equipped with boxes or platforms for ballast loading and shall be loaded so that the tire print width of each wheel is not less than the clear distance between tire prints.

1.5.5 Mechanical Spreaders

The spreaders shall be adjustable and capable of spreading aggregate at controlled amounts per square yard, as specified.

1.5.6 Brooms and Blowers

The machines shall be of the power type, capable of cleaning surfaces to be treated.

1.5.7 Scales

The scales shall be standard truck scales of the beam type equipped with a weight-recording device. The scales shall be sufficient in size and capacity to accommodate the trucks used in hauling aggregates. The scales shall be tested and approved by an inspector of the State Inspection Bureau charged with scale inspection within the state in which the project is located. If an official of the inspection bureau is not available, the scales shall be tested in accordance with state specifications in the presence of the Contracting Officer. Keep the necessary number of standard weights on hand, at all times, for testing the scales.

1.5.8 Weighhouse

Provide a weatherproof weighhouse constructed in a manner to afford adequate protection for the indicating and recording devices of the scales.

1.6 SUBMITTALS

Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-03 Product Data

Waybills and Delivery Tickets

Copies of waybills and delivery tickets during progress of the work.

Cutback Asphalt; G Asphalt Cement; G Temperature-viscosity relationship of cutback asphalt and asphalt cement.

SD-06 Test Reports

Tests

Copies of test results, within 24 hours after completion of each test.

1.7 QUALITY ASSURANCE

1.7.1 Safety Precautions

No smoking, or open flames shall be permitted within 25 feet of heating, distributing, or transferring operations of bituminous materials other than bituminous emulsions. When tar is used, a full-face, organic, vapor-type respirator and protective creams shall be used by personnel exposed to fumes. Protective creams shall not substitute for cover clothing.

1.7.2 Sampling and Testing

Sampling and testing is the responsibility of the Contractor. Sampling and testing shall be performed by an approved commercial testing laboratory, or by the Contractor, subject to approval. Sampling shall be in accordance with ASTM D 75 for aggregates and ASTM D 140 for bituminous material, unless otherwise directed. Perform aggregate gradation tests on each sample in accordance with ASTM C 136. Perform all other aggregate tests on the initial source samples and repeat tests when there is a change of source. Perform sieve analyses daily from material samples. The tests shall include an analysis of each gradation of material. Perform tests in sufficient number to ensure that materials meet specified requirements.

1.7.3 Wear Test

Perform the wear test in accordance with ASTM C 131 to ensure that aggregates have a percentage of wear not exceeding 40 percent after 500 revolutions. One test shall be performed for every 20,000 cubic yards of aggregates in stockpiles or at the source.

1.7.4 Soundness Test

Perform the soundness test as specified by ASTM C 88 to ensure that aggregates have a weight loss not greater than 12 percent when subjected to five cycles of the magnesium sulfate test. One test shall be performed for every 20,000 cubic yards of aggregates in stockpiles or at the source.

1.7.5 Stripping Test

Perform stripping tests meeting the requirements of ASTM D 3625. Deleterious substances shall not exceed the requirements of ASTM D 1139.

1.8 DELIVERY, STORAGE, AND HANDLING

Inspect the materials delivered to the site for contamination and damage. Unload and store the materials with a minimum of handling. Store aggregates preventing segregation and contamination.

1.9 ENVIRONMENTAL REQUIREMENTS

Apply bituminous surface treatment only when the existing surface or base course is dry or contains moisture not in excess of the amount that will permit uniform distribution and the desired adhesion. Bituminous surface treatment shall not be applied when the air temperature is 60°F and above, or above 50°F and rising.

PART 2 PRODUCTS

2.1 MATERIALS

Use mineral aggregate and bituminous material of the following types, gradations, grades, and consistencies that meet the requirements of stripping, wear, and soundness tests as specified in paragraph SAMPLING AND TESTING.

2.1.1 Mineral Aggregate

Provide aggregate consisting of crushed stone, crushed gravel, or crushed slag of such nature that thorough coating of bituminous material, used in the work, will not strip off upon contact with water. Moisture content of the aggregate shall be such that the aggregate will be readily coated with the bituminous material. Drying may be required, as directed. Aggregate shall conform to the gradation shown below. Determine gradation of the aggregates by ASTM C 136.

AGGREGATE GRADATION

SINGLE BITUMINOUS SURFACE TREATMENT

(PERCENT BY WEIGHT PASSING)

Sieve Designation

No.1

No.2

No.3

1 inch

3/4 inch

90-100

1/2 inch

20-55

90-100

3/8 inch

0-15

40-70

85-100

No. 4

0-5

0-15

10-30

No. 8

0-5

0-10

No. 16

0-5

AGGREGATE GRADATION

DOUBLE BITUMINOUS SURFACE TREATMENT

(PERCENT BY WEIGHT PASSING)

Sieve Designation

No. 1

No. 2

No. 3

No. 4

1 inch

3/4 inch

90-100

1/2 inch

20-55

90-100

3/8 inch

0-15

85-100

40-70

No. 4

0-5

10-30

0-15

85-100

No. 8

0-10

0-5

10-40

No. 16

0-5

0-10

No. 50

0-5

2.1.1.1 Crushed Stone

Provide crushed stone consisting of clean, sound, durable particles, free of soft or disintegrated pieces, dust, or foreign matter.

2.1.1.2 Crushed Gravel

Provide crushed gravel consisting of clean, sound, durable particles, free of soft or disintegrated pieces or foreign matter. At least 90 percent by weight of the particles shall have at least two fractured faces.

2.1.1.3 Crushed Slag

Provide crushed slag which is an air-cooled blast-furnace product having a dry weight of not less than 70 pcf, and consists of angular particles uniform in density and quality and free of dust and foreign matter. Determine the weight of a cubic foot of slag aggregate by ASTM C 29.

2.1.1.4 Aggregate Quantities

The bituminous material and aggregate shall be spread within the quantity limits shown below. The individual quantities of bituminous material and aggregate may be varied to meet specific field conditions at all times during progress of the work, as directed, without adjustments to contract unit prices. Aggregate weights shown are for aggregates having a specific gravity of 2.65. If the specific gravity of the aggregate used is other than 2.65, appropriate adjustments shall be made in number of pounds required to ensure a constant volume of aggregate per square yard of treatment.

QUANTITIES (PER SQUARE YARD

FOR SINGLE SURFACE TREATMENT

Gradation No.

Bituminous material (Gallons)

Aggregate (Pounds)

0.30-0.45

35-50

0.15-0.30

20-35

0.10-0.20

15-25

QUANTITIES (PER SQUARE YARD)

FOR DOUBLE SURFACE TREATMENT

Gradation No.

Bituminous material (Gallons) First Application

Aggregate (Pounds) First Spreading

Bituminous material (Gallons) Second Application

Aggregate (Pounds) Second Spreading

0.20-0.30

28-34

0.20-0.30

20-25

0.15-0.20

20-25

0.15-0.20

10-15

2.1.2 Bituminous Materials

2.1.2.1 Cutback Asphalt

Rapid curing cutback asphalt shall conform to ASTM D 2028, Designation RC-250, RC-800 or RC-3000.

2.1.2.2 Emulsified Asphalt

Rapid-setting emulsified asphalt shall conform to ASTM D 977, Grade RS-1 or RS-2 or ASTM D 2397, Grade CRS-1 or CRS-2.

2.1.2.3 Asphalt Cement

Asphalt cement shall conform to ASTM D 946, Penetration Grade 120-150 or ASTM D 3381, Viscosity Grade AR2000. Shall be acceptable to local air pollution regulations.

PART 3 EXECUTION

3.1 SURFACE PREPARATION

Immediately before applying the first course of bituminous material, clean the surface of loose material with power brooms or power blowers. Take care to remove all dirt, clay, and other loose or foreign matter. Flush the surface with water, when necessary to achieve a clean surface, only when directed by the Contracting Officer; allow the surface to dry after flushing.

3.2 APPLICATION OF FIRST COURSE

3.2.1 Bituminous Material

Apply bituminous material by means of a bituminous distributor at the temperature specified in paragraph APPLICATION TEMPERATURE OF MATERIALS, below or as directed; and within the limits specified in paragraph QUANTITY LIMITS in PART 1. Apply bituminous material in such a manner that uniform distribution is obtained over all surfaces treated. Unless the distributor is equipped to obtain a satisfactory result at the junction of previous and subsequent applications, building paper shall be spread on the surface for a sufficient distance back from the ends of each application so that flow through the sprays may be started and stopped on the paper in order that all sprays will operate at full force on the surface treated. Immediately after application, remove and destroy the building paper. Areas inaccessible to the distributor shall be properly treated with bituminous material using the hose attachment. Protect adjacent buildings, structures, and trees to prevent their being spattered or marred.

3.2.2 Spreading of Aggregate

Immediately following application of bituminous material, spread aggregate uniformly over the surface within the limits of the quantities specified in paragraph QUANTITY LIMITS in PART 1. Spreading shall be done with mechanical spreaders. Spread aggregate evenly by hand on all areas missed by the mechanical spreader. Equipment spreading aggregate shall be operated backwards, so that the bituminous material will be covered ahead of the truck wheels. When hand spreading is employed on inaccessible areas, spread aggregate directly from trucks. Additional aggregate shall be spread by hand over areas having insufficient cover, and spreading shall continue during these operations when necessary.

3.2.3 Brooming and Rolling

Roll the surface with a pneumatic-tired and a steel-wheeled roller after sufficient aggregate is spread. Continue rolling until no more aggregate can be worked into the treated surface. The use of the steel-wheeled roller will be discontinued, or a lighter weight steel wheel roller substituted, as directed, if the roller being used causes excessive crushing and shattering of the aggregate. If the aggregate is not distributed properly, broom the surface as soon as possible after the first coverage by the roller, but not until the surface has set sufficiently to prevent excessive marking. Brooming, rolling, and supplemental spreading of aggregate shall continue until the surface is cured and rolled sufficiently to key and set the aggregate. In places not accessible to rollers, compact the aggregate with pneumatic tampers. Aggregate that becomes contaminated with foreign matter shall be removed, replaced with clean aggregate, and rerolled, as directed. Maintain and protect the treated areas by use of barricades for a period not to exceed 30 days.

3.3 APPLICATION OF SECOND COURSE

3.3.1 Bituminous Treatment

Apply the bituminous material for the second course within 48 hours after construction of the first course, weather permitting. Remove excess aggregate prior to the second application of bituminous material. If the treated surface is excessively moistened by rain, allow the surface to dry for such time as deemed necessary. Perform the second application of bituminous material in the manner specified in paragraph APPLICATION OF FIRST COURSE, including temperature and QUANTITY LIMITS.

3.3.2 Aggregate

Immediately following the second application of bitumen, aggregate conforming to the gradation and limits specified in paragraph QUANTITY LIMITS shall be spread uniformly over the bituminous material and processed in the manner specified for the first course.

3.3.3 Brooming and Rolling Second Course

The surface shall be rolled and broomed in the manner specified for the first course until a thoroughly bonded, smooth, even-textured surface is produced. Sweep off the surface surplus aggregate and remove it prior to final acceptance.

3.4 APPLICATION TEMPERATURE OF MATERIALS

3.4.1 Cutback Asphalt

Use Saybolt Furol as necessary to provide an application viscosity between 40 and 120 centistokes, kinematic or 20 and 60 seconds.

3.4.2 Emulsified Asphalt

Within the following ranges:

RS-1: 70-140 degrees F.

RS-2, CRS-1 and CSR-2: 125-185 degrees F.

3.4.3 Asphalt Cement

Use Saybolt Furol as necessary to provide an application viscosity between 40 and 120 centistokes, kinematic or 20 and 60 seconds.

3.5 TRIAL APPLICATION

Preliminary to providing a complete surface treatment, treat three lengths of at least 100 feet each for the full width of the distributor bar. Use the appropriate typical application rates specified herein for one surface treatment trial. Make other surface treatment trials using various amounts of materials as may be deemed necessary.

3.6 PROTECTION

Keep all traffic off surfaces freshly treated with bituminous material. Provide sufficient warning signs and barricades so that traffic will not travel over freshly treated surfaces. Protect the treated areas from traffic for at least 24 hours after final application of bituminous material and aggregate, or for such time as necessary to prevent picking up. Immediately prior to opening to traffic, roll the entire treated area with a self-propelled pneumatic-tired roller.

3.7 DISPOSITION OF MATERIAL

All waste materials demolished shall be removed from the government property to an approved landfill site.

--End of Section--