29 TREATED PERMEABLE BASES
29-1 General
29-1.01 General
29-1.01A Summary
Section 29 -1 includes general specifications for constructing treated permeable bases .
29-1.01B Definitions
Reserv ed
29-1.01C Submittals
Submit a treated permeable base quality control plan.
29-1.01D Quality Assurance
29-1.01D(1) General
Reserved
29-1.01D(2) Quality Control
29-1.01D(2)(a) General
Reserved
29-1.01D(2)(b) Quality Control Plan
Reserved
29-1.01D(2)( c) Qualifications
Reserved
29-1.01D(3) Department Acceptance
Reserved
29-1.02 Materials
Not Used
29-1.03 Construction
29-1.03A General
Immediately before spreading the treated permeable base, the subgrade must:
1.Comply with the specified compaction and elevation tolerance for the material involved
2.Be fr ee from loose or extraneous material
3.Be uniformly moist Areas of subgrade lower than the grade established by the Engineer must be filled with permeable base. Spread the permeable base when the atmospheric temperature is above 40 degrees F. Finish the permeable base to a uniform surface within 0.05 foot of the grade established by the Engineer. Place filter fabric on the edge and on the top of the high side, the side opposite the edge drain side, of the treated permeable base and at intermediate cross d rain interceptors. Place filter fabric under section 68 - 1.03. Place and compact the treated permeable base for edge drains under section 68 -4.03.
29-1.03B Surfaces Out of Tolerance
Where the surface of the permeable base is higher than 0.05 foot from the grade established by the Engineer, remove the base and replace it with the specified treated permeable base. If authorized, remove high spots to comply with the specified tolerance by any method that does not produce contaminating fines or damage the base remaining in place. Grinding is not allowed. SECTION 29 TREATED PERMEABLE BASES Where the surface of the treated permeable base is lower than 0.05 foot from the grade established by the Engineer, remove the base and replace it with the specifi ed treated permeable base. If authorized, fill low areas with pavement material as follows:
1.For HMA pavement, fill low areas with HMA that complies with the specifications for the lowest layer of HMA pavement. Do not fill low areas concurrently with the HMA paving operation.
2.For concrete pavement, fill low areas with paving concrete concurrent with the concrete pavement paving operation.
29-1.04 Payment
The payment quantity for treated permeable base is the volume determined from the dimensions show n. The payment quantity for treated permeable base does not include:
1.Quantity used for edge drains installed adjacent to the treated permeable base
2.Treated permeable base used to fill low areas of subgrade
29-2 Asphalt Treated Permeable Bases
29-2.01 General
29-2.01A Summary
Section 29 -2 includes specifications for constructing asphalt treated permeable bases.
29-2.01B Definitions
Reserved
29-2.01C Submittals
Reserved
29-2.01D Quality Assurance
29-2.01D(1) General
The Engineer determines the asphalt content of the asphalt mixture under California Test 382. The bitumen ratio, pounds of asphal t per 100 lb of dry aggregate, must not vary more than 0.5 lb of asphalt above or below the quantity designated by the Engineer. Samples used to determine the bitumen ratio are obtained from trucks at the plant or from the mat behind the paver before rolli ng. If the sample is taken from the mat behind the paver, the bitumen ratio must not be less than the quantity designated by the Engineer, less 0.7 lb of asphalt per 100 lb of dry aggregate.
29-2.01D(2) Quality Control
29-2.01D(2)(a) General
Reserved
29-2.01D(2)(b) Quality Control Testing
ATPB quality control must include testing the quality characteristics at the frequencies shown in the following table: SECTION 29 TREATED PERMEABLE BASES QC Testing Frequencies Quality characteristic Test method Sampling location Minimum frequency Gradation California Test 202 Stockpiles or plant 1 for every 4 hours of production but at least one per day of placement Cleanness value California Test 227 Stockpiles or plant 1 for every 4 hours of production but at least one per day Percentage of crushed particles California Test 205 Stockpiles or plant 1 test before production and one every 5,000 cu yd thereafter Los Angeles rattler loss at 500 rev California Test 211 Stockpiles or plant 1 test before production and one every 5,000 cu yd thereafter Film stripping California Test 302 Plant 1 test before production and one every 5000 cu yd thereafter Asphalt content of the asphalt mixture California Test 382 Plant, transportation units, windrows, or roadway 1 for every 4 hours of production but at least one per day
29-2.01D(3) Department Acceptance
The Department accepts ATPB based on aggregate gradation, cleanness value, percent of crushed particles, Los Angeles rattler, film stripping and asphalt content requirements specified in section 29 -2.02 and section 29 -2.01D(1). The Engineer takes samples for aggregate gradation, cleanness value, percent of crushed particles, Los Angeles rattler, and film stripping from the plant. The Engineer takes samples for asphalt content of the asphalt mixture from any of the following locations:
1.Plant
2.Truck
3.Windrow
4.Roadbed
29-2.02 Materials
29-2.02A General
Aggregate for ATPB must be clean and free from decomposed material, organic material, and other deleterious substances. Produce ATPB under section 39 -2.01B(8), except a JMF is not required. Do not use RAP. The temperature of the aggregate must be from 275 to 325 degrees F before adding the asphalt binder. Do not store ATPB material longer than 2 hours. Combine aggregate with 2.5 percent asphalt binder by weight of dry aggregate. An increase or decrease in the asphalt content may be ordered after your proposed aggregate supply has been tested.
29-2.02B Aggregate
The aggregate must comply with the gradation shown in the following table: SECTION 29 TREATED PERMEABLE BASES Aggregate Gradation Sieve size Percentage passing 1" 100 3/4" 90–100 1/2" 35–65 3/8" 20–45 No. 4 0–10 No. 8 0–5 No. 200 0–2 The aggregate must comply with the requirement s shown in the following table: Aggregate Requirements Quality characteristic Test method Requirement Percentage of crushed particles (min, %) California Test 205 90 Los Angeles rattler loss at 500 rev (max, %) California Test 211 45 Cleanness value (min) California Test 227 57 Film stripping (max, %) California Test 302 25
29-2.03 Construction
Equipment for spreading and compacting ATPB must comply with section 39-2.01C(2) except, c ompact ATPB in 1 layer using one of the following methods:
1.One complete coverage with a steel -tired, 2 -axle tandem roller that has an operatin g weight below 110 lb per linear inch of steel -tire width. Compact when the base mixture is from 200 to 250 degrees F.
2.One complete coverage with a steel -tired, 2 -axle tandem roller weighing from 8 to 12 tons. Compact when the base mixture is from 100 to 150 degrees F. Do not use water to cool the ATPB. Vibratory rollers complying with the above requirements may be used if the vibratory unit is turned off.
29-2.04 Payment
The Department adjusts the unit price of asphalt treated permeable base if a n ordered increase or decrease in asphalt content exceeds the specified amount by more than 0.1 percent by weight of dry aggregate.
29-3 Cement Treated Permeable Base
29-3.01 General
29-3.01A Summary
Section 29 -3 includes specifications for constructing cement treated permeable bases.
29-3.01B Definitions
Reserved
29-3.01C Submittals
Reserved
29-3.01D Qual ity Assurance
29-3.01D(1) General
Reserved SECTION 29 TREATED PERMEABLE BASES
29-3.01D(2) Quality Control
29-3.01D(2)(a) General
Reserved
29-3.01D(2)(b) Quality Control Testing
CTPB quality control must include testing the quality characteristics at the frequencies shown in the followin g table: QC Testing Frequencies Quality characteristic Test method Sampling location Minimum frequency Gradation California Test 202 Stockpiles or plant 1 for every 4 hours of production but at least one per day of placement Cleanness value California Test 227 Stockpiles or plant 1 for every 4 hours of production but at least one per day Los Angeles rattler loss at 500 rev California Test 211 Stockpiles or plant 1 test before production and one every 5,000 cu yd thereafter Soundness California Test 214 Stockpiles or plant 1 test before production and one every 5,000 cu yd thereafter
29-3.01D(3) Department Acceptance
The Department accepts CTPB based on aggregate gradation, cleanness value, Los Angeles rattler and soundness requirem ents in section 29 -3.02. The Engineer takes samples for aggregate gradation, cleanness value, Los Angeles rattler and soundness from the plant.
29-3.02 Materials
29-3.02A General
Cement must comply with section 90 -1.02B(2). The cement content of CTPB mus t be at least 287 lb/cu yd. The water -cement ratio must be approximately 0.37. The Engineer determines the exact water -cement ratio. Water must comply with section 90 -1.02D.
29-3.02B Aggregate
Aggregate for CTPB must comply with section 90 -1.02C. Aggregate gradation must comply with the specifications for the 1 inch x no. 4 primary aggregate nominal size coarse gradation in section 90 - 1.02C(4)(b).
29-3.03 Construction
Store, proportion, mix, and transport aggregates, cement and water, under sectio ns 90 -1.02F and 90 - 1.02G except aggregate does not have to be separated into sizes and the quantity of water and penetration requirements do not apply. Place CTPB under section 40 -1.03F(1) exce pt the 4th paragraph does not apply. Spread, compact, and shape CTPB under section 40 -1.03F(4) or under section 40 -1.03F(5). Vibrators must not be used. Compact with a 2 -axle steel -tired roller we ighing from 6 to 10 tons. Compact within 30 minutes after spreading the CTPB. Compaction must consist of 2 complete passes of the CTPB. Cure CTPB by sprinkling the completed surface with a fine spray of water every 2 hours for a period of 8 hours. Start cu ring the morning after base has been placed. SECTION 29 TREATED PERMEABLE BASES
29-3.04 Payment
Not Used
29-4 29-7 Reserved
Source: California Standard Specifications, 2024 Edition. Pages 437–442 of 1,372.