This work consists of constructing a base course of aggregate and asphalt binder, mixed in a central plant and spread and compacted on a prepared surface.

The requirements of Item 401 apply, except as modified by this specification.

Composition (301.02)

The contractor should furnish aggregate for the mix that conforms to the following gradation:

Sieve Size	Total Percent Passing
2 inch (50 mm)	100
1 inch (25.0 mm)	75 to 100
1/2 inch (12.5 mm)	50 to 85
No. 4 (4.75 mm)	25 to 60
No. 8 (2.36 mm)	15 to 45
No. 16 (1.18 mm)	10 to 35
No. 50 (300 µm)	3 to 18
No. 200 (75 µm)	1 to 7

The Contractor may use 10 to 50 percent of reclaimed asphalt concrete pavement in Item 301 Asphalt Concrete Base. The Laboratory will establish the JMF according to 401.02.

Asphalt concrete is sampled and tested by the contractor at the asphalt plant. Contractor tests are used for pay if they are verified by District testing. See 403.06 for sampling detail.

Spreading and Finishing (301.04)

The contractor should notify the Engineer at least 24 hours before starting paving and the minimum air temperature required for paving is 40 °F (5 °C). Spreading Equipment should conform to 401.12 specifications. Ensure that paver is approved by the Office of Materials Management.

Hauling conforms to specification 401.11

The contractor should use trucks for hauling asphalt concrete that have tight, clean, smooth metal beds from which the entire quantity of mixture is discharged smoothly into the spreading equipment.

If transporting hot asphalt concrete at prevailing air temperatures below 50 °F (10 °C) or if the length of haul exceeds 20 miles (32 km), ensure that all truck beds are insulated to maintain workable mix temperature, and that all covers are fastened to exclude the wind. Do not exceed a distance of 50 miles (80 km) from the asphalt concrete plant to the paving site except by specific permission of the Department.

Compaction conforms to specification 401.16

Compact the mixture uniformly using a combination of both steel and Type I pneumatic tire rollers conforming to 401.13. Do not use a spreading rate that exceeds the total of the specified capacities of the rollers in use.

Example: Roller Capacity and Placement Rate

A contractor is using one three-wheel roller, one vibratory roller with 66-inch drums (both vibrating) and one Type 2 pneumatic tire roller to compact a mat 5 inch thick using material with Lab conversion factor of 2.0 tons per cubic yard.

From Table 401.13-1 the following is the capacity of the rollers the contractor will use:

· Three wheel = 700 sq yd/hr

· Vibratory roller = 2 drums x 66 in x (15 sq yd/in of width) = 1980 sq yd/ hr

· Type II Pneumatic Roller = 700 sq yd/hr

· Maximum roller capacity = 700 + 1980 + 700 = 3380 square yards/hour

3380 yd²/hr X (5 in ÷ 36 yd³/in³) = 469.44 yd³/hr.

469.44 yd³ X 2.0 tons/Yd³ = 938.88 tons per hour maximum placement rate.

Ensure that the maximum compacted depth of any one layer is 6 inches (150 mm) and the temperature of the mixture when delivered to the paver (not to the job site) is a minimum of 250 °F (120 °C).

Spreading and Surface Tolerances (301.05)

Spread the mixture at a rate calculated using the specified thickness and the compacted width of the pavement course being placed, and the weight-to-volume conversion factors established in 401.21. Maintain the actual rate of spreading the mixture within a tolerance of ±5 percent.

Example: Determining the Required Placing Rate per Station (RPRS)

A contractor is placing a 5 inch uniform mat of asphalt concrete pavement whose Lab conversion factor is 2.0 tons/cubic yard. The required placing rate (RPRS) in tons of material per station for a 12 ft wide mat is:

RPRS = [Volume of asphalt in cubic yards] x [Lab Conversion Factor]

= [100 ft X 12 ft X (5 in ÷ 12 in/ft) ÷ 27 ft³/ yd³] X 2.0 tons/yd³

= 37.04 tons/station

Do not exceed 3/8 inch (10mm) in variation from the edge of a 10 foot (3 m) straightedge. If using Item 301 Asphalt Concrete Base as a subbase for a rigid Pavement or base, do not exceed a variation of ¼ inch (6 mm).

Documentation Requirements - 301 Asphalt Concrete Base

1. State condition of base (example: primed 304, clean and dry concrete, etc.)

2. Write location on tickets where material is placed

3. Mark on ticket time unloaded

4. Obtain temperature of the mix at project site and place this information on ticket of load checked. This should be done a minimum of four times daily or any time temperature is in question.

5. State kind of rolling equipment and maximum tons per hour they are allowed to cover. See Example Roller Capacity and Placement Rate

6. Calculate and document the required placement rate (Tons/Station)

7. Document on form CA-FP-4

8. Lift thickness if required

9. Tickets should be totaled with initialed and dated tape attached

302 Asphalt Concrete Base

Description (302.01)

This work consists of constructing a base course of aggregate and asphalt binder, mixed in a central plant and spread and compacted on a prepared surface.

The requirements of Item 401 apply, except as modified by this specification.

Composition (302.02)

The contractor should furnish aggregate for the mix that conforms to the following gradation:

Sieve Size	Total Percent Passing
2 inch (50 mm)	100
1 1/2 inch (37.5 mm)	85 to 100
1 inch (25.0 mm)[1]	68 to 88
3/4 inch (19.0 mm)[1]	56 to 80
1/2 inch (12.5 mm)[1]	44 to 68
3/8 inch (9.5 mm)[1]	37 to 60
No. 4 (4.75 mm)	22 to 45
No. 8 (2.36 mm)	14 to 35
No. 16 (1.18 mm)	8 to 25
No. 30 (600 µm)	6 to 18
No. 50 (300 µm)	4 to 13
No. 200 (75 µm)	2 to 6
[1] Provide aggregate to retain a minimum of 7 percent of the material on each of these sieves. This requirement applies to the gradation of the JMF and the mix production according to Item 403.

The Contractor may use a maximum of 40 percent of reclaimed asphalt concrete pavement.

Asphalt concrete is sampled and tested by the contractor at the asphalt plant. Contractor tests are used for pay if they are verified by District testing. See 403.06 for sampling detail.

Spreading and Finishing (302.04)

Hauling conforms to specification 401.11

The contractor should use trucks for hauling asphalt concrete that have tight, clean, smooth metal beds from which the entire quantity of mixture is discharged smoothly into the spreading equipment.

Compaction conforms to specification 401.16

Example: Roller Capacity and Placement Rate

From Table 401.13-1 the following is the capacity of the rollers the contractor will use:

· Three wheel = 700 sq yd/hr

· Vibratory roller = 2 drums x 66 in x (15 sq yd/in of width) = 1980 sq yd/ hr

· Type II Pneumatic Roller = 700 sq yd/hr

· Maximum roller capacity = 700 + 1980 + 700 = 3380 square yards/hour

3380 yd²/hr X (5 in ÷ 36 yd³/in³) = 469.44 yd³/hr.

469.44 yd³ X 2.0 tons/Yd³ = 938.88 tons per hour maximum placement rate.

Ensure that the compacted depth of any one layer is a minimum of 4 inches (100 mm) and a maximum of 7.75 inches (190 mm). Ensure that the temperature of the mixture when delivered to the paver is a minimum of 250 °F (120 °C), and is sufficient for the roller coverage to be effective in compacting the mixture.

Spreading and Surface Tolerances (302.05)

Example: Determining the Required Placing Rate per Station (RPRS)

RPRS = [Volume of asphalt in cubic yards] x [Lab Conversion Factor]

= [100 ft X 12 ft X (5 in ÷ 12 in/ft) ÷ 27 ft³/ yd³] X 2.0 tons/yd³

= 37.04 tons/station

Do not exceed 3/8 inch (10mm) in variation from the edge of a 10 foot (3 m) straightedge. If using Item 302 Asphalt Concrete Base as a subbase for a rigid Pavement or base, do not exceed a variation of ¼ inch (6 mm).

Documentation Requirements - 302 Asphalt Concrete Base

1. State condition of base (example: primed 304, clean and dry concrete, etc.)

2. Write location on tickets where material is placed

3. Mark on ticket time unloaded

4. Obtain temperature of the mix at project site and place this information on ticket of load checked. This should be done a minimum of four times daily or any time temperature is in question.

5. State kind of rolling equipment and maximum tons per hour they are allowed to cover. See example Roller Capacity and Placement rate.

6. Calculate and document the required placement rate (Tons/Station). See example Determining the Required Placing Rate per Station (RPRS).

7. Document on form CA-FP-4

8. Lift thickness if required

9. Tickets should be totaled with initialed and dated tape attached

304 Aggregate Base

Specification Changes

1. Prior to spreading use material with moisture content not less then -2 percent of optimal content.

2. Prior to compaction use material with moisture content +/- 2 of optimal moisture content.

3. Contractor is required to cover up any 304 with the next pavement layer prior to the end of the construction season.

a. Contractor assumes liability if not done.

4. Consistent depths below specified thickness is not allowed.

a. Corrective methods are defined.

i. Reference is made to the Construction Inspection Manual of Procedures.

Materials (304.02)

All of the material requirements for 304 are located in section 703.17. This section allows the use of the following five material types:

1. Crushed carbonate stone (CCS)

2. Crushed gravel

3. Crushed air cooled blast furnace slag (ACBFS)

4. Granulated slag (GS)

5. Open hearth slag (OH)

Crushed Carbonate Stone (Limestone) Used for 304

If crushed carbonate stone (CCS) is used, the material must meet the gradation and physical requirements in 703.17.

In rare cases, these materials become soft after a rain event or over the winter.

Crushed Gravel Used for 304

If crushed gravel is selected for use as 304 it must be manufactured from material retained on the ½ inch (12.5 mm) sieve. It must meet the gradation and physical requirements shown in 703.17.

At times, this material is missing some fine material and can become unstable.

Crushed Air Cooled Blast Furnace Slag Used as 304

If air cooled blast furnace slag is selected for use, insure that the material meets the requirements of Supplement 1027. This material can cause environmental concerns. The gradation and physical requirements are detailed in 703.17.

Granulated Slag Used for 304

If granulated slag is selected for use, the material must meet the requirements of 703.08.

Open Hearth Slag Used as 304

If open hearth slag is selected for use, insure that the material meets the gradation and physical requirements of 703.17 and the requirements of 703.14 which include:

1. Deleterious Substances

2. Identification of OH Slag

3. Tufa Performance Verified

4. Aging and Stockpiling Requirements

5. Expansion Testing

Prior to Spreading (304.03)

1. Sample the material to be used.

a. Develop a moisture density curve per Supplement 1015.

2. Material Moisture

a. The material must have reasonably uniform moisture content

b. Use a moisture content not less than minus 2 percent of optimum moisture prior to spreading.

c. Add water to the stockpile, if required.

3. Minimize segregation.

a. If segregation occurs, mix or re-grade the stockpile.

Spreading (304.04)

1. Do not spread on frozen material.

2. Do not use frozen material.

3. Do not exceed a compacted lift thickness of:

a. 8 inches (200 mm) when using vibratory rollers greater than 12 tons (11 metric tons).

b. 6 inches (200 mm) with vibratory rollers weighing 10 to 12 tons (9 to 11 metric tons).

c. 4 inches (100 mm) with no vibratory roller.

d. Can use a lighter roller with equivalent centrifugal force.

i. Centrifugal force is the weight with vibration.

e. Contractor needs to document the roller weight requirements are met.

4. Place in equal lifts when the specified thickness exceeds 8 inches (200 mm).

a. Example: if 12-inch lift is specified, place in two 6 inch lifts.

Spreading 304 with a Dozer and Spreader Box

Spreading 304 with an Asphalt Paver

5. Use self-propelled spreading machines.

a. Capable of placing the 304 material true to line and grade.

b. Use a dozer with a spreader box or an asphalt paver.

i. This operation prevents segregation.

c. Allowed to use dozers without spreader boxes or graders.

i. If these are used take in-place gradation tests.

1. According to Supplement 1090.

2. Test after spreading but before compaction testing.

Spreading 304 with a Dozer or with a Grader May Result in Segregation

Compaction (304.05)

Adding Water to 304 Prior to Compaction

Compacting 304 with Vibratory Roller

1. Add water or dry out the material.

a. To bring material to +/- 2 percent of the optimum moisture content.

b. Add water or dry the 304 prior to compaction.

i. Material is too dense to add water after compaction.

c. Maintain moisture during compaction.

d. Uniformly apply water throughout the lift.

e. Reduce when unstable.

2. Compact immediately after spreading.

Construct a Test Section

Perform the Compaction Tests

3. Construct a short test section.

a. Compaction testing according to Supplement 1015.

b. Use a minimum of eight passes in the test section.

i. Minimizes getting a false maximum.

4. Use and adjust the vibration.

a. Maximize density and stability.

b. When vibration at maximum can make any material unstable.

5. Use 98 percent for the acceptance in the production area.

a. Take 3 tests in the lot for acceptance.

b. Use the average of the results.

6. Use at least:

a. Same number of passes and compactive effort used to obtain the test section maximum density for the production material.

i. Increases passing results in the production area.

7. At a minimum, use eight passes in the production area.

a. Increases passing results.

8. Reduce minimum passes if detrimental.

a. Do not over roll it may cause cracking.

9. Construct a new test section when.

a. Material changes.

b. Supporting materials change.

10. Check production material density.

a. Before or after the finishing operations.

11. Maintain the surface

a. So that the texture is:

i. Reasonably uniform.

ii. Aggregate firmly keyed.

iii. Hauling on the 304 will ‘Un-key’ the material.

12. Scheduling 304 operations

a. Cover the aggregate base with the next pavement layer prior to the end of the construction season.

b. Contractor accepts responsibility for contamination, damage and instability of the base, subgrade and underdrains if not covered prior to winter months.

13. Provide drainage and maintain the material according to 203.04.A.

a. Maintain the cross slope.

b. If it rains or material sits over the winter.

i. Dry the 304 and subgrade.

ii. Obtain and maintain stability and density.

Finished Surface (304.06)

1. Finished surface so that does not vary:

a. More than 3/8 inch (10 mm).

i. From a 10-foot (3 m) straightedge parallel to the centerline.

b. Or more than 1/2 inch (13 mm).

i. From a template conforming to the required cross-section.

2. Contractor to furnish straightedges, templates, or other devices.

Checks of the Depth (304.06)

1. At the beginning of the spreading operation.

a. Contractor must adjust the spreader.

i. Produce sufficient loose depth to meet plan compacted thickness.

1. Determined after compaction.

ii. Make occasional checks.

1. During the spreading to insure uniform depth after compaction.

b. Purpose is to control spreading.

i. Need not be recorded.

2. After fine grading:

a. Make depth checks.

i. At 500 ft. (150 m) intervals.

ii. Extended to 1,000 ft. (300 m).

1. If depth is consistent and meets plan depth.

b. Variations in depth is expected.

i. Tolerance of 3/4 in. (19 mm).

ii. Between individual measurements.

c. If consistently less by any amount.

i. Requirements have not been met.

ii. Take corrective action.

d. If individual measurement.

i. Less than 3/4 in. (19 mm) of plan depth.

1. Make measurement within 100 ft. (30 m).

2. If greater than plan thickness.

a. Satisfactory.

3. If less than plan thickness.

a. Make checks at additional locations.

b. Define deficient area.

c. Require correction.

e. Record all depth measurements.

i. With station locations.

ii. Place in the project records.

Checks of the Width (304.06)

1. Measurements of the width of base.

a. Need not be made prior to placement of overlying courses because the width of base can readily be verified.

2. After the overlying pavement is placed make a visual verification of the base width.

a. If it conforms to or exceeds the plan width.

i. File a statement in the project records.

Documentation Requirements - 304 Aggregate Base

1. Materials

2. Roller weights

3. Record lift thickness

4. Segregation.

5. Roller passes

6. Perform the compaction tests according to S-1015

7. Verify cross section and thickness.

8. In place gradation tests according to S-1090, if required.

9. Obtain weight ticket, if required. Tickets should be totaled with initialed and dated tape attached. Convert to cubic yards (cubic meters) as per 304.07 of the C&MS

10. Pay and measure according to 304.07 and 304.08

11. Document on the CA-EW-12 and CA-D

a. Do not duplicate the information on these forms unless necessary.

305 Portland Cement Concrete Base

Construction

When constructing this item, the requirements of 451 apply with the following exceptions:

1. Reinforcing mesh required by 451.07 is not required in concrete base.

2. The curing application rate for the membrane forming curing compound for concrete base is 200 square feet per gallon (5 square meters per liter) instead of what is specified for 451 and 452 pavement described in 451.10.

3. Transverse contraction joints must be sealed with a hot applied joint sealer conforming to 705.04. Longitudinal joints do not require any joint sealer.

4. The surface finish for concrete base is a broom dragged in either the longitudinal or the transverse direction to provide a uniform, gritty surface texture to the satisfaction of the Engineer. Transverse grooving as per 451.09 is not required for base pavement that is overlaid with asphalt concrete.

5. Surface smoothness variations for concrete base are not to exceed 1/4 inch in 10 feet (6 mm in 3 m).

6. Station numbers required in 451.09 are not required for concrete base.

Method of Measurement

The concrete base must be field measured and the area of pavement placed calculated for payment in square yards (square meters). The area is determined the same as for 451 or 452 pavement.

Basis of Payment

Pay a reduced price for base found deficient in thickness according to 451.17. There is no additional payment for a concrete base thicker than that shown in the plans. Pay for accepted quantities at the contract price per square yard (square meter).

Documentation Requirements - 305 Portland Cement Concrete Base

305 concrete base is the same as 451 concrete except as noted in 305.02.

306 Cement Treated Free Draining Base

Materials (306.02)

The cement treated free draining base (CTFDB) is to be a mixture of coarse aggregate, Portland cement and water.

Cement used must be Type 1A (701.01) or Type I (701.04) conforming to ASTM C 150.

The coarse aggregate used can be either No. 57 or No 67 size per Table 703.01-1

Proportioning, Mixing and Transporting

The Contractor must proportion, mix and transport the CTFDB according to Item 499.

The mix is to be prepared as follows:

Use a minimum cement content of 250 pounds per cubic yard (148 kg/m³) when using No. 57 size coarse aggregate and it must be 220 pounds per cubic yard (130 kg/m³) when using No. 67 size.

The water-cement ratio is to be 0.36.

A water- reducing admixture meeting 705.12 can be used.

Verification of Design

The Contractor must submit a mix design for the proposed CTFDB 30 days prior to the start of production. This mix design must detail the proposed aggregate size, the cement content and the water content by weight. A private laboratory must perform tests on the proposed mix to verify the yield of the mix design.

Inspection should include random sampling of the CTFDB material delivered to the project to insure conformance to the mix design. The unit weight of the mix must be determined and the yield checked.

Equipment

The Contractor must provide all equipment necessary to mix, transport, place, compact and finish the CTFDB. Equipment must be approved before the work begins.

A spreader must be used if the width being placed is more than 12 feet or the total area of any given width exceeds 5000 square yards (4000 m²) of area. The spreader could be a concrete spreader or an asphalt paving machine.

Initial compaction may be done by using a steel wheel roller, a modified slip-form paving machine with vibratory plates or high-density screed pavers. Compaction must not crush aggregate particles or cause segregation. Final compaction must be done with steel wheel rollers weighing 6 to 10 tons (5 to 9 metric tons). If vibratory rollers are used, do not use them in vibratory mode.

Spreading with an Asphalt Paving Machine

Spreading CTFDB with a Concrete Spreader

Placing and Spreading

The Contractor must thoroughly moisten the base, if there is no prime coat specified in the contract, prior to placing the CTFDB. Workers must not contaminate the CTFDB by walking through it with mud other foreign material on their work shoes.

The CTFDB must be spread in a smooth uniform layer prior to compacting it.

Inspection should include sampling the CTFDB mixture and testing for in place gradation after it is spread and before compaction. This testing is to be done in accordance with Supplement 1090.

Limitations on Placing Operations

Minimum temperature is required to be 35 F (2 C) and rising.

The material is not placed on frozen material or on rain softened subgrade or base.

Vibrating Plate behind Concrete Spreader

Steel Wheel Roller Compact the CTFDB

Compaction and Shaping

The CTFDB is to be shaped to produce a uniform density and cross-section. Compaction must not cause crushing of the aggregate particles.

The Contractor must make a minimum of two passes over any given area with the required steel wheel rollers.

Construction joints between each days work must be made by cutting transversely across the hardened CTFDB with diamond saws or the contractor is permitted to use forms to form the construction joints.

Curing CTFDB with 6-mil White Opaque Polyethylene Sheeting

Curing

Curing of CTFDB is to be done by placing 6-mil (150 um) white opaque polyethylene sheets over the completed work. These coverings must be left in place for a minimum of three days. A cure day is defined as 24 consecutive hours of time in which the temperature is above 40 F (5 C). Add a cure day for each day the temperature falls below 40 F (5 C). Do not allow the use of liquid concrete curing membranes for curing.

Protection of Underdrains

Care must be exercised by the contractor so as to not damage any installed underdrains during placing or compacting of the CTFDB. The Contractor must ensure positive connection between the underdrain backfill and the CTFDB at all times during construction.

Protection of Cement Treated Free Draining Base

The Contractor is permitted to haul materials or operate equipment on completed CTFDB provided there is no significant displacement, breakup or contamination. If any of this occurs, the Contractor must stop using the completed CTFDB for such purposes until the Contractor can demonstrate to the Department that it will not happen again in the future. Any damage to the CTFDB must be corrected by the contractor at no cost to the State.

The Contractor must protect the completed CTFDB from contamination from fine material at all times.

The Contractor must use track mounted asphalt paving machines for placing the first lift of asphalt concrete on top of completed CTFDB. This first course must cure at a minimum over-night before placing succeeding lifts of asphalt concrete.

Thickness Tolerance

The compacted depth of the CTFDB is to be 4 inches (100 mm) with a tolerance of ± ½ inch (13 mm). Depth checks must be made every 2000 square yards (1650 m²). Areas found to be out of this tolerance must be removed and replaced at no cost to the Department and retested for proper thickness.

Surface Tolerance

The CTFDB must be constructed to the proper elevation and have the plan specified cross-slope. Checks should be made periodically to verify these parameters. The surface tolerance of the finished surface must not vary more than ½ inch from a 10 foot (13 mm from a 3 m) straightedge. Any irregularities exceeding this amount must be corrected by the Contractor.

Exposure to Elements

The Contractor is required to place the next pavement layer on top of the CTFDB within 40 days from the end of the curing period. In addition, the Contractor must plan the work such that the CTFDB is completely covered with the next pavement layer and have the underdrain system in place and functioning by the end of the construction season in any calendar year.

Method of Measurement and Basis of Payment

The project will measure and calculate the area in square yards (square meters) based on the typical sections shown on the plans. Payment will be made at the contract bid price for work that is accepted in place.

Documentation Requirements - 306 Cement Treated Free Draining Base

1. Materials

2. Verify design

3. Proportioning and mixing as per 306.03.

4. Prime base or sprinkle base with water

5. Temperature must be above 35° F (1.6° C)

6. Use a spreader, if project quantity exceeds 5,000 square yards (4,181 square meters)

7. Compact and cure in accordance with 306.08, and 306.09

8. Check segregation and thickness.

9. Curing and protection.

10. Pay and measure according to 306.15 and 306.16.

11. Document on the CA-EW-12 and CA-D

a. Do not duplicate the information on these forms unless necessary.

307 Non-Stabilized Drainage Base

Specification Changes

There were no specification changes to this specification.

Materials (307.02)

The aggregate used for this item of work must be crushed carbonate stone (CCS), crushed gravel or air cooled blast furnace slag (ACBFS). Non-stabilized drainable base (NSDB) can be specified as any one of three gradations. The three gradations are Type NJ, Type IA and Type CE (see 703.12 B). The type of gradation to be used will be called out in the pay item description in the contract. The physical requirements for the aggregate used in this item are shown in 703.13 C.

Mixture Composition and Verification of Design (307.04)

The contractor is required to submit a computed blend of aggregate that meets the gradation called out on the project within 30 days prior to production. The submitted gradation must be based on the percentage, by dry weight, of aggregate passing each required sieve size shown in 703.12 B. Approval of the submitted gradation will be based on whether the values of the percentage passing each sieve size are within the specification band for each sieve size.

The Department will take random samples at the aggregate blending site or at the point of use after spreading to ensure conformance to the specified gradation.

Placement of NSDB with Spreader Box and an Asphalt Paving Machine

Equipment (307.05)

The contractor is required to provide equipment to mix, transport, place, compact and finish the NSDB. The equipment to be used by the contractor must be approved by the Department prior to use.

1. Mixing Equipment. If the contractor uses a pugmill mixer to blend aggregates for NSDB, it can be either stationary or portable. The pugmill can be a continuous or a batch type mixer equipped with batching or metering devices for proportioning the blend of aggregate and water. The equipment must be capable of producing a blended material that consistently meets the specified gradation requirements.

2. Hauling Equipment. Vehicles used for hauling the NSDB must prevent contamination, degradation and segregation of the mixture.

3. Spreading Equipment. A spreader box or asphalt paving machine capable of maintaining a uniform rate of travel and laying a layer of uniform consistency and thickness with grade control.

4. Compaction Equipment. The contractor must use static or vibratory rollers to compact the NSDB. For Type IA and Type NJ bases, the contractor must use 8 to 10 ton (7 to 9 metric tons) steel wheel static rollers. For Type CE base the contractor must use a vibratory roller with a minimum weight or centrifugal force of 10 tons (9metric tons) for compaction.

Compaction of NSDB

Compaction Measurement with Nuclear Gage

Spreading and Compaction (307.09 & 307.10)

Spread the NSDB with a minimum of manipulation to prevent segregation. Spreading equipment must be equipped with grade control. Test for in place gradation before compaction according to Supplement 1090.

To determine the project compaction requirements, construct one or more test section according to Supplement 1015. Compact the test section by using two passes of a static roller for a Type NJ base and use four passes for a Type IA base. Use six passes with a vibratory roller for a Type CE base. A pass is defined as one passage of a compacting unit over the entire surface of the layer. Compact the test section until maximum density is achieved. Measure the compaction according to Supplement 1015. Compact the test section until the maximum dry density is achieved.

The contractor must use the same number of passes and moisture content used to obtain the maximum dry density in the test section for the production areas. Compaction is required immediately after spreading.

All production areas must be compacted to ensure that the average dry density is greater than 95% of the average maximum test section dry density. Any production areas that do not meet the 95% of the average maximum test section density must be re-compacted and re-tested. If re-testing indicates that the lot fails to meet 95% of the average test section density, the lot must be replaced.

Checking for Proper Finishing

Final Compacted Surface of a NSDB

Shaping and Finishing (307.11)

After compaction, the contractor must shape the NSDB to the cross-section shown in the plans. If shaping reduces the density, the contractor must re-compact the area to conform to the original density.

Limitations on Placing (307.12)

Do not place frozen NSDB material or place NSDB material on frozen material. Do not place NSDB when rain has softened the underlying base course or subgrade. The contractor must not place material in weather conditions which cause degradation, segregation or contamination.

Protection of Underdrains and the NSDB (307.13)

The contractor must not damage the underdrain system during placement or compaction of the HSDB. The contractor must provide a positive connection between the underdrain backfill and the NSDB at all times.

The contractor must not use NSDB as a haul road after placement. Keep hauling units and other construction vehicles off of all Type NJ or Type IA material. The contractor can operate hauling units for less than 50 feet (15 m) to access a paving machine on Type CE material. For Type NJ and Type IA bases, the contractor must use side dump equipment when placing the next pavement layer.

The contractor must protect the NSDB from fine material contamination at all times. Contamination with fine material will not allow the drainable base to drain properly.

When constructing an asphalt pavement on a NSDB, the contractor must use a paving machine mounted on tracks. Any asphalt course placed on top of a NSDB must cure overnight before the next layer is placed. Hauling equipment must be kept off of the pavement until there is a minimum of 7 ½ inches (190 mm) of asphalt concrete placed on top of the NSDB.

Thickness and Surface Tolerances (307.14)

The contractor must provide a maximum compacted thickness of 4 inches (100 mm) with a tolerance of ±1/2 inch (±13 mm). Thin areas are to be corrected by adding material, grading and re-compacting.

The finished surface of the NSDB must be uniform and must not vary more than ¼ inch (6 mm) from a 10 foot (3 m) straightedge placed on the surface parallel to the pavement centerline. The contractor must provide templates, slope boards or other devices to verify surface tolerance.

Exposure to the Elements (307.17)

The contractor must place the next pavement layer on top of the NSDB within 40 days of the construction of the NSDB. The contractor must schedule the work on the project such that all NSDB is covered with the next pavement layer and the underdrain system is placed and working before atmospheric temperature falls below 35 F (2 C) or by the end of the construction season in any calendar year.

Method of Measurement and Basis of Payment (307.12)

The Department measures this item of work by the number of square yards of 4 inch (100 mm) Non-Stabilized Drainable Base of the type specified. The area is calculated from measurements along the profile grade and using the plan typical sections.

The Department will pay for this work at the unit price bid for accepted quantities.

Documentation Requirements - 307 Non Stabilized Drainage Base

1. Materials

2. Verify design

3. Aggregates for material approved 30 days before use

a. Take random samples of material during placement for mix design requirements

b. Do not place on frozen material, rain softened subgrade, or any weather that may contaminate material

4. Segregation and thickness.

5. Gradation according to S-1090.

6. Roller weights and passes

7. Perform the compaction tests according to S-1015.

8. Protection.

9. Pay and measure according to 307.18 and 307.19

10. Document on the CA-EW-7, CA-EW-12 and CA-D

a. Do not duplicate the information on these forms unless necessary.

308 Asphalt Treated Free Draining Base

Description (308.01)

This work consists of constructing asphalt treated free draining base (ATFDB) course, mixed in a central plant and spread and compacted on a prepared surface. The (ATFDB) drainage layer is immediately beneath the pavement and is made of graded aggregate, asphalt-treated permeable material. Construction of this drainage layers will serve satisfactorily as drains and as structural support for the surfacing materials.

The requirements of Item 401 apply, except as modified by the 308 specification.

Materials & Composition (308.02 & 308.03)

The aggregate gradation should conform to 703.01-1 and 703.04 with the exceptions detailed in 308.02 and the binder should be PG 64-22 conforming to the requirements of 702.01. The contractor is not allowed to use reclaimed asphalt concrete pavement in the mix.

The binder amount should equal to 1.5 to 3.5 percent by weight of the mix with the aggregate. Ensure that the aggregate does not show excess drainage at 250 °F (120 °C) and is coated with shiny black coating of asphalt binder.

Brown or dull mix appearance is not acceptable and is a sign of excess aggregate absorption of the asphalt binder or low asphalt binder content. Minor bare aggregate exposure is acceptable.

Design Verification (308.04)

A minimum of 3 weeks before the production of the ATFDB, the contractor should submit a computed blend of aggregate and asphalt binder, using standard JMF submittal forms, and production temperature range to the Laboratory for initial design verification. The contractor should notify the Laboratory before the delivery of any material.

Final design verification is subject to field verification and actual performance. Field verification may include additional testing by the Laboratory.

Rollers (308.06)

The contractor should use only tandem steel wheel rollers weighing 6 to 10 tons (5.5 to 9 metric tons) for compaction.

Weather Limitations (308.07)

The contractor should spread the (ATFDB) mix only when the atmospheric temperature is above 45 °F (7 °C).

Cease all operations if rain occurs during placement of the (ATFDB), or when rain is imminent. Do not spread on frozen material.

Spreading and Compacting (308.08)

The contractor should spread the (ATFDB) material in a method that produces a smooth, uniform layer before compacting. Cease all operations when signs of degradation, segregation, or contamination are evident. Communicate with the contractor and the material monitor to resolve the problem before resuming placement.

The contractor should compact the (ATFDB) sufficiently, by compacting the layer at least two roller passes over any given point, unless otherwise directed by the engineer for more passes. Do not over compact the (ATFDB) to the extent where the aggregate particles are crushed or broken. Complete rolling before the mix temperature has dropped to less than 100 °F (38 °C).

Do not cool ATFDB with water.

Form transverse construction joints by cutting back into the completed work to form a vertical face.

If significant breakup of the ATFDB occurs at or near the outer portion of a lift during the compaction operation, provide lateral support using forms or other methods approved by the Engineer at no additional cost to the Department. Do not contaminate the ATFDB with this lateral support.

When the ATFDB is placed in areas inaccessible to rollers, compact it using a method approved by the Engineer.

After compaction has been completed, do not place the next layer of pavement on the ATFDB until the next day.

Thickness Tolerances (308.09)

The compacted thickness of the ATFDB layer should be 4 inches (100 mm). Ensure the placed ATFDB conforms to the specified thickness by randomly checking the thickness during construction. The district could run a (dry-rodded unit weight) to establish a conversion factor that could be used to establish the required placement rate as per 401. Also, since the loose layer does not compact much a check using a prod should be used frequently to check the layer thickness. Remove all sections found to be ±1/2 inch (±12 mm) from the specified thickness and replace them with ATFDB at no additional expense to the Department.

Surface Tolerance (308.10)

Ensure that the finished surface is uniform and varies no more than 1/2 inch (12 mm) from a 10-foot (3 m) straightedge applied to the surface parallel to the centerline of the pavement. Remove any section found to be out of tolerance and replace it with ATFDB within the specified tolerance at no additional expense to the Department.

Quality Control and Acceptance (308.11)

The quality control and acceptance requirements of Item 403 apply, except as detailed in 308.11. Project administrators should check with the district lab to insure material conformance to the specifications.

The ATFDB should be coated with shiny black coating of asphalt binder and not be brown or dull in appearance. Minor inconsistent bare aggregate exposure is acceptable. If the delivered mix is brown or dull in appearance, immediately inform the district lab and the contractor to adjust the asphalt binder content.

Underdrains (308.12)

Ensure that the underdrain system is functional before placing the ATFDB. Do not allow construction equipment to crush the underdrain pipe or system as a result of the placement or compaction of the ATFDB. Ensure a positive connection between the underdrain system and the ATFDB regardless of the sequence of operations in the Contract Documents.

Protection of the ATFDB (308.13)

The ATFDB is not designed to carry construction traffic. The Engineer will allow hauling units and other construction vehicles to operate on the ATFDB provided no significant displacement, breakup, or contamination occurs. If the Engineer determines significant displacement, breakup, or contamination of the ATFDB is occurring, the Contractor shall stop operating hauling units and construction vehicles on the ATFDB. The contractor should repair or replace all damage to the ATFDB, subbase, subgrade, or underdrains caused by the hauling units or construction vehicles at no additional expense to the Department.

The ATFDB layer should be protected from fine material contamination, and adequate surface and subsurface drainage for the ATFDB, subbase, and subgrade should be provided at all times.

The Contractor may use a rubber tire paver if it does not damage the ATFDB, subbase, subgrade, or underdrains. If damage occurs, cease paving and switch the rubber tire paver with a track mounted paver before restarting the paving.

When constructing asphalt concrete pavement on the ATFDB, allow the first course to cure overnight before placing the succeeding pavement courses.

Exposure to the Elements (308.14)

The ATFDB layer should be covered by constructing the pavement within 40 days, and before the atmospheric temperature falls below 35 °F (2 °C) for any period of time

The contractor should remove and replace all damage caused to the ATFDB, subbase, subgrade, or underdrains by the exposure to temperatures below 35 °F (2 °C) at no additional expense to the Department.

Method of Measurement (308.15)

The Department will measure the accepted quantities of Asphalt Treated Free Draining Base by the number of square yards (square meters). The Department will measure the width as the width of the asphalt treated free draining base shown on the typical sections of the plans and additional widening where called for, or otherwise directed in writing by the Engineer. The Department will measure the length horizontally along the centerline of each roadway or ramp.

Basis of Payment (308.16)

The Department will pay for accepted quantities, complete in place, at the contract price as follows:

Documentation Requirements - 308 Asphalt Treated Free Draining Base

1. State condition of base (example: primed 304, clean and dry concrete, etc.)

2. Write location on tickets where material is placed

3. Mark on ticket time unloaded

4. Obtain temperature of the mix at project site and place this information on ticket of load checked. This should be done a minimum of four times daily or any time temperature is in question.

5. State kind of rolling equipment.

6. Calculate and document the required placement rate (Tons/Station)

7. Document on form CA-FP-4 Project documents compliance with Item 308 on Form CA-D-3A and measurements on CA-D-1 and 2

8. Document Lift thickness

9. Tickets should be totaled with initialed and dated tape attached

320 Rubblize and Roll

Description (320.01)

This work consists of the full-depth removal of existing rigid pavement in areas exhibiting deterioration, correcting the subgrade, placing and compacting asphalt concrete, and restoring the shoulders.

Materials (320.03)

The contractor should furnish materials conforming to Item 304 to Fill depressions 1 inch (25 mm) or greater in depth.

Equipment (320.03)

The contractor should use a self-contained and self-propelled unit of either the resonant frequency type or the multiple head breaker type for rubblizing the exposed concrete pavement. Check specification 320.03 for more details.

The contractor should use a vibratory roller.

Construction Details (320.04)

Saw Cutting

The contractor should make a full depth saw cut or cut load transfer devices at existing joints on ramps or mainline where the rubblizing abuts concrete pavement or approach slabs that are to remain in place permanently or temporarily for maintenance of traffic.

Test Section

After rubblizing and rolling for one station long or so, the Engineer should designate a test section, cut the reinforcing steel, and excavate through the thickness of the concrete, to ensure that the Rubblize and Roll activity is breaking down the existing pavement to proper particle size.

The Engineer may require additional test pits as necessary, throughout the rubblizing operation.

Control and Operating Speed

The Engineer may adjust the rubblizing procedure by controlling the operating speed of the equipment used to maintain the proper particle sizes.

Control the operating speed of the rubblizing equipment such that the existing pavement is reduced into proper particle sizes.

Proper Particle Size

Particles sizes should range from sand sized to pieces not exceeding 6 inches (150 mm) in their largest dimension. The majority being a nominal 1 to 2 inches (25 to 50 mm) in size.

Reduce the portion of the concrete slab above the reinforcing steel to 1 to 2 inches (25 to 50 mm) in size.

Filling & Compacting

Leave steel reinforcement in place in the rubblized pavement. However, cut off any steel reinforcement exposed at the surface as a result of rubblizing or compaction operations, below the surface and remove it from the site.

Before placing the initial asphalt concrete course fill in the test pit using the excavated material and additional filler aggregate conforming to Item 304 as necessary.

Compact The Test Pit As Part Of The Rolling Operation.

Compact the rubblized pavement with two passes of the vibratory roller. Operate the roller in the vibratory mode and at a speed not to exceed 6 feet (1.8 m) per second.

Fill depressions 1 inch (25 mm) or more in depth below the immediate surrounding area, resulting from the rubblizing, the compaction, or the steel reinforcement removal, with filler aggregate conforming to Item 304.

Strike off level with the surrounding area the excess filler aggregate. Compact filled depressions with the same roller and compactive effort previously described.

Compact the rubblized pavement with two passes. Operate the roller in the vibratory mode and at a speed not to exceed 6 feet (1.8 m) per second.

Restrictions

Do not allow traffic on the rubblized pavement before the initial asphalt concrete base and intermediate courses are in place.

Do not allow more than 48 hours to elapse between rubblizing the pavement and placing the initial asphalt concrete course. However, in the event of rain, the Engineer may waive this time limitation to allow sufficient time for the rubblized pavement to dry to the Engineer’s satisfaction.

If the Engineer waives the time limitation, cease rubblizing the pavement until the Engineer allows paving to resume.

Method of Measurement (320.05)

The Engineer will measure Rubblize and Roll by the number of square yards (square meters).

The Engineer will use the actual width of the existing concrete pavement and will measure the length along the centerline of each roadway or ramp.

The Engineer will measure the Filler Aggregate by the number of cubic yards (cubic meters) furnished, placed, and compacted.

The Engineer will use CA-D-3A to document measurements.

Documentation Requirements - 320 Rubblize and Roll

1. Document procedure and measure for payment, use CA-D-3A

321 Cracking and Seating Existing Plain Concrete Pavement

Description (321.01)

This work consists of cracking and seating existing plain concrete pavement or concrete base before placing an asphalt concrete pavement.

Equipment (321.02)

Equipment used should be capable of producing the desired crack pattern without extensive spalling over 1.25 inches in depth or excessive shattering. Pneumatic tire roller used should comply with specification 204.06

Whiphammers are not allowed.

Construction Details (321.03)

The contractor should provide positive provisions in addition to 107.07 to contain any flying debris during cracking operation.

The contractor should demonstrate to the engineer the ability of the selected equipment and procedure to produce desired crack pattern. The contractor should crack at least three, but no more than five existing concrete slabs, and furnish and apply water to dampen the cracked concrete to enhance visual determination or the crack pattern. The contractor should make adjustments to the energy or striking pattern to maintain the crack pattern desired.

Desired crack pattern is 4 ft X 4ft (1.2 m X 1.02 m) segments.

The engineer should determine the maximum number of coverages of the roller on the test section to ensure proper seating of segments without damage to the concrete.

If existing concrete slabs have an existing crack pattern, the contractor should crack these segments further into nominally equal sized pieces having longitudinal and transverse dimensions not more than 5 feet (1.5 m) and not less than 3 feet (0.9 m), wherever feasible. Do not allow the cracking equipment to impact the slabs within 1 foot (0.3 m) of another break line, joint, or the edge of the concrete.

The contractor should roll the cracked concrete, and remove and repair all loose pieces of broken concrete that are not firmly seated. The contractor should repair all voids by applying 407 tack coat, filling with asphalt concrete, and compacted as directed by the Engineer.

Traffic in not allowed on the cracked concrete before the initial asphalt concrete base and the intermediate courses are in place.

Documentation Requirements - 321 Cracking and Seating Existing Plain Concrete Pavement

Document equipment used

Document contractor provisions to contain any flying debris during cracking operation

Document cracked concrete segments nominal sizes

Document roller coverages needed.

Document location and pay quantity (Square Yards) using CA-D-3A