151(a) Lightweight aggregate used in hydraulic cement concrete shall conform to AASHTO M195.
b.Lightweight aggregate used for asphalt surface treatment shall conform to AASHTO M195 except that Sections 3, 6, and 8 will not apply. Grading shall conform to Table II-3 except that the maximum percentage by weight of material passing the No. 8 sieve shall be 16 percent and passing the No. 16 sieve shall be 9 percent. SECTION 207—SELECT MATERIAL
207.01 Description
These specifications cover nonplastic material obtained from roadway cuts, borrow areas, or commercial sources used as foundation for subbase, shoulder surfacing, fill, backfill, or other specific purposes.
207.02 Detail Requirements
Select material shall consist of approved local or commercial materials free from roots, muck, and debris.
a.Grading:
1.Type I: Grading for Type I shall conform to the job-mix formula selected from within the design range specified in Table II-6, subject to the applicable tolerances specified in Table II-7 when tested in accordance with VTM- 25. TABLE II-6 Design Range: Select Material, Type I % by Weight of Material Passing Sieve 3 in 2 in No. 10 No. 40 No. 200 ASTM D4791 Flat & Elongated 5:1 100 95-100 25-55 16-30 4-14 30% max.
2.Type II and Type III: Grading for Types II and III shall conform to the following when tested in accordance with VTM-25: % by Weight of Material Passing Sieve Type 3 in 2 in No. 200 II Min. 100 Min. 100 Max. 25 III1 Max. 20 1A maximum of 25 percent of m aterial retained on the No. 200 sieve will be allowed for Type III if the liquid limit is less than 25 and the plasticity index is less than 6.207.02 152207.02 TABLE II-7 Process (P) and Range (R) Tolerance: Select Material, Type I Tolerance on Each Laboratory Sieve (%) 3 in 2 in No. 10 No. 40 No. 200 No. Test P R P R P R P R P R 1 0.0 ±4.0 ±15.0 ±10.0 ±6.0 2 0.0 0.0 ±3.0 5.0 ±10.5 18.5 ±7.0 13.0 ±4.0 8.5 3 0.0 0.0 ±2.5 5.5 ±8.5 22.0 ±5.5 15.0 ±3.5 10.0 4 0.0 0.0 ±2.0 6.0 ±7.5 23.5 ±5.0 16.5 ±3.0 10.5 8 0.0 0.0 ±1.5 7.0 ±5.5 26.5 ±3.0 18.5 ±2.0 12.0
b.Atterberg Limits:
1.Type I: The mean of the Atterberg limits shall conform to Table II-8 when tested to verify acceptance in accordance with VTM-7. TABLE II-8 Process (P) and Range (R) Tolerance: Select Material, Type I No. Tests Max . Liquid Limit Max . Plasticity Index 1 25.0 6.0 2 23.9 5.4 3 23.2 5.1 4 23.0 5.0 8 22.4 4.7
2.Types II and III: Atterberg limits shall conform to the following values when tested in accordance with VTM-7: Type Max . Liquid Limit Max . Plasticity Index II 30 9 III1 30 9
c.California Bearing Ratio (CBR): Tests for CBR shall be performed in accordance with VTM-8 for conformance to the specified value.
d.Soundness: Soundness for Type 1 shall conform to Table II-4. Tests shall be performed in accordance with AASHTO T103 or T104.
e.Flat and Elongated Particles: Select materials to be used as a temporary riding surface during construction activities or as the final riding surface after construction shall contain not more than 30 percent by mass of aggregate particles retained on and above the 3/8-inch sieve having a maximum to minimum dimensional ratio greater than 5 as determined in accordance with ASTM D4791. 153207.05
f.Crushed glass that conforms to the physical requirements set forth in the Specifications shall be limited to Type II and Type III applications to exclude those applications listed in Section 203.02(d).
207.03 Job-Mix Formula for Select Material, Type I
The Contractor shall submit or shall have the source of supply submit a job-mix formula for each mix - ture for the Engineer’ s approval through the “Producer Lab Analysis and Information Details” (PLAID) website https://plaid.vdot.virginia.gov prior to starting work. The formula shall establish a single percentage of aggregate passing each required sieve size denoted in Table II-6 and shall be in effect until a modification is approved by the Engineer. If unsatisfactory results or other changed conditions make it necessary, the Contractor shall prepare and submit a new job mix formula for the Engineer’ s approval.
207.04 Mixing
The Contractor shall provide a laboratory as specified in Section 106.07. Select material shall be produced at optimum moisture ±2 percentage points. The Contractor shall have a certified Central Mix Aggregate Technician present at the aggregate plant during initial setup and subsequent production.
207.05 Acceptance of Select Material, Type I
The Contractor shall perform sampling and testing for determination of grading, moisture, and Atterberg limits. The Contractor shall provide such test results within 48 hours of sampling to the Department through the “Producer Lab Analysis and Information Details” (PLAID) website https://plaid.vdot.vir - ginia.gov. The Contractor shall maintain appropriate, current quality control charts. The Department will perform independent monitor tests. If there is a statistically significant difference between the two sets of results, the Department will conduct an investigation to determine the reason for the difference. If it is determined that the material does not conform to the requirements of the Contract, the Engineer will reject the material or make an adjustment in payment adjustment in accordance with Section 207.07. Determination of gradation and Atterberg limits will be based on a mean of the results of tests per - formed on four samples taken in a stratified random manner from each lot. The Engineer may use lots of 2000 tons or 4000 tons at the Engineer’ s discretion when warranted by annual plant shipping quantity and past performance. If visual examination reveals that the material is obviously contaminated or segregated, the material will be rejected without additional sampling or testing. If it is necessary to determine the gradation and Atterberg limits of the material in an individual location, one sample taken from the material in question will be tested and the results will be compared to the job-mix formula with the tolerances specified in Table II-7 and Table II-8 for one test. The results obtained will apply only to the material in question. A lot will be considered acceptable for grading if the mean of the test results falls within the allowed deviation from the job-mix formula and the difference between the maximum and minimum results does not exceed the range values specified in Table II-7. A lot will be considered acceptable for Atterberg limits if the mean of the test results is less than the maximum allowed for the liquid limit and plasticity index values specified in Table II-8. 154If the liquid limit exceeds 30 or the plasticity index exceeds 9 on any individual sample, that portion of the lot from which the sample was taken will be considered a separate part of the lot and shall be removed from the road. If the Contract specifies less than 2,000 tons of material, the amount of material necessary to complete the last lot is less than 2,000 tons (or 4,000 tons, if applicable), the job-mix formula is modified within a lot, or a portion of the lot is rejected on the basis of individual test results, the mean results of the tests on the samples taken will be compared to the job-mix formula with the applicable process tolerances specified in Table II-7 and Table II-8 for the number of tests performed.
207.06 Referee System for Select Material, Type I
If the test results obtained for one of the four samples is questionable or the mean of the four samples tested to evaluate a particular lot is questionable, the Engineer will apply the referee system specified in Section 208.07 except that the final mean results will be compared to the job-mix formula with the tolerances given in Table II-7 and Table II-8 for the mean of eight tests.
207.07 Payment Adjustment System for Select Material, Type I
If a lot of material does not conform to the acceptance requirements stated herein, adjustment points, determined as follows, will be applied for each 1 percent or part thereof that the grading or Atterberg limits are outside the job-mix formula with the tolerances given in Table II-7 and Table II-8. Adjustment Points Sieve Size Process Range 3-in 1 1 2-in 1 1 No. 10 1 1 No. 40 3 3 No. 200 5 5 Atterberg Limits Adjustment Points Liquid limit 3 Plasticity index 7 If it is determined the total adjustment (excluding the range adjustment) for the lot is more than 25 points, the failing material shall be removed from the roadway. If the total adjustment (excluding the range adjustment) is 25 points or less and the Contractor does not elect to remove and replace the material, the Contract unit price for the material will be reduced by 1 percent for each adjustment point. The total adjustment will be applied to the tonnage in the Contract represented by the sample(s).207.05 155SECTION 208—SUBBASE AND AGGREGATE BASE MATERIAL
208.01 Description
These specifications cover material used to form a foundation for base or surface pavement.
208.02 Materials
a.Subbase material shall consist of mixtures of natural or crushed gravel, crushed stone or slag, and natural or crushed sand, with or without soil mortar.
b.Aggregate base material will be designated as Type I or Type II as follows: Type I shall consist of crushed stone, crushed slag, or crushed gravel, with or without soil mortar or other admixtures. Crushed gravel shall consist of particles of which at least 90 percent by weight of the material retained on the No. 10 sieve shall have at least one face fractured by artificial crushing. Type II shall consist of gravel, stone, or slag screenings; fine aggregate and crushed coarse aggregate; sand-clay-gravel mixtures; or any combination of these materials; with or without soil mortar or other admixtures.
208.03 Detail Requirements
a.Grading: Grading shall conform to the requirements of the job-mix formula selected from within the design range specified in Table II-9, subject to the applicable tolerances specified in Table II-10 when tested to verify acceptance in accordance with VTM-25. TABLE II-9 Design Range for Dense-Graded Aggregates Amounts Finer Than Each Laboratory Sieve (Square Openings1) (% by Weight) Size ASTM D4791 Flat & No. 2 in 1 in 3/8 in . No. 10 No. 40 No. 200 Elongated 5:1 21A 100 94-100 63-72 32-41 14-24 6-12 30% max. 21B 100 85-95 50-69 20-36 9-19 4-7 30% max. 22 --- 100 62-78 39-56 23-32 8-12 30% max. 1In inches, except where otherwise indicated. Numbered sieves are those of the U.S. Standard Sieve Series. TABLE II-10 Process Tolerances for Each Laboratory Sieve (%) No. Tests Top Size 1 in 3/4 in . 3/8 in . No. 10 No. 40 No. 200 1 0.0 ±10.0 ±14.0 ±19.0 ±14.0 ±8.0 ±4.0 2 0.0 ±7.1 ±10.0 ±13.6 ±10.0 ±5.7 ±2.9 3 0.0 ±5.6 ±7.8 ±10.6 ±7.8 ±4.4 ±2.2 4 0.0 ±5.0 ±7.0 ±9.5 ±7.0 ±4.0 ±2.0 8 0.0 ±3.6 ±5.0 ±6.8 ±5.0 ±2.9 ±1.4208.03
Source: Virginia Road and Bridge Specifications, 2020 Edition. Pages 179–182 of 1,065.