Category:1002 Aggregate for Asphaltic Concrete

This guidance establishes procedures for the inspection, testing and acceptance of coarse aggregate, fine aggregate, hydrated lime, and mineral filler for use in asphaltic concrete.

1002.1 Procedure

Inspection, testing, and sampling will also be governed by the instructions contained in General Requirements for Material.

Field tests required are as follows:

Samples required for Laboratory tests are as follows:

(a) Initial Evaluation for coarse aggregate.

(b) Source Approval.

(c) Trial Mix samples.

1002.2 Acceptance

Source Approval is to be based on the results of Laboratory tests. Acceptance is based on routine tests in the field to ensure compliance with Sec 1002.

Acceptance or rejection of aggregates for asphaltic concrete will be on the basis of quality requirements of Standard Specification Sec 1002, placing full responsibility for obtaining the proper gradation shown on the approved job mix formula on the contractor. It is expected, however, that the District Construction and Materials Engineer will cooperate with the contractor by keeping him informed as to whether the produced material can be combined to meet the gradation shown in the approved job mix formula.

If the contractor desires to have material produced to comply with gradations that he has selected as being more applicable to the approved job mix, he shall furnish the necessary gradation requirements to the District Construction and Materials Engineer and the aggregate producer in writing. The inspector should then immediately notify both the contractor and the producer when the material, as produced, approaches or exceeds these additional limits. This procedure should be explained to all contractors so that they may proceed on that basis, if they prefer. Where contractors are not willing to furnish adequate and definite instructions, the basis of acceptance or rejection of the material will be as described in paragraph 1002.2.1 above.

1002.3 Records and Reports

All plant records shown in General Requirements for Material - Records and Reports shall be maintained. The aggregate shall be reported through SiteManager in accordance with Automation Section 3510.

1002.4 Qualified Mineral Filler for Stone Matrix Asphalt (SMA)

Mineral filler shall be in accordance with M 17 and shall meet the requirements of Specification Section 1002.4 in Sec 1002. Upon approval of the mineral filler, the manufacturer and product will be added to the list “Qualified Mineral Filler for SMA”.

1002.5 Laboratory Testing for Sec 1002

1002.5.1 Types of Samples Tested

1002.5.1.1 Initial Approval Sample

Tests consist of specific gravity, absorption, and Los Angeles abrasion. The minimum time required for completion of tests is four working days from the date received. Test results and calculations shall be recorded through SiteManager.

1002.5.1.2 Source Approval Sample

Coarse aggregate tests for source approval consist of sieve analysis, specific gravity, absorption, Los Angeles abrasion, and deleterious content. The minimum time required for completion of tests is four working days from the date received. Test results and calculations shall be recorded through SiteManager.

Fine aggregate tests for source approval consist of sieve analysis; specific gravity; other deleterious substances, clay lumps, and shale; and lightweight particle content when specified. The minimum time required for completion of tests is four working days from the date received. Test results and calculations shall be recorded through SiteManager.

1002.5.1.3 Trial Mix Samples

Coarse aggregate tests for trial mix consist of sieve analysis, specific gravity, absorption, plastic index (when required), deleterious content, sand equivalency (T176) and uncompacted voids (T304). The minimum time required for completion of tests is four working days from the date received. Test results and calculations shall be recorded through SiteManager.

Fine aggregate tests for trial mix consist of sieve analysis, specific gravity, plastic index (when required), other deleterious substances, clay lumps and shale, and lightweight particle content when specified. The minimum time required for completion of tests is four working days from the date received. Test results and calculations shall be recorded through SiteManager.

Mineral filler tests for trial mix consist of sieve analysis and specific gravity. The minimum time required for completion of tests is two working days from the date received. Test results and calculations shall be recorded through SiteManager.

1002.5.2 Procedure

1002.5.2.1 Sieve Analysis

Fine and coarse aggregate shall be tested in accordance with AASHTO T 27.

Mineral filler and hydrated lime shall be tested in accordance with AASHTO T 37.

1002.5.2.2 Specific Gravity

Coarse aggregate submitted for Source or Initial Approval shall be tested in accordance with AASHTO T85 for bulk specific gravity.

Coarse aggregate submitted for SuperPave Trial Mix designs shall be tested in accordance with the following:

• If 10.0% or less passes the #4, test the plus #4 material using AASHTO T 85 and discard the minus #4 material. Report the results.
• If more than 10.0% passes the #4 and more than 10.0% passes the #8, test the plus #4 using AASHTO T 85 and the minus #4 using AASHTO T 84. Use the AASHTO T 85 method for combining and averaging the results. Report the average.
• If more than 10.0% passes #4 and 10.0% or less passes the #8, test the plus #8 material using AASHTO T 85 and discard the minus #8 material. Report the result.

Fine aggregate submitted for Superpave (Trial Mix) shall be tested by AASHTO T84 for bulk specific gravity.

Mineral filler and hydrated lime shall be tested in accordance with MoDOT Test Method T37.

1002.5.2.3 Absorption

Coarse aggregate shall be tested in accordance with AASHTO T 85 for Initial Samples, Source Samples and Trial Mix to be used in mixtures which are defined by Standard Specifications 401, 402, and 403.

Coarse aggregates submitted for SUPERPAVE Trial Mix designs shall be tested in accordance with AASHTO T85 for absorption.

Fine aggregate shall be tested in accordance with AASHTO T84.

1002.5.2.4 Los Angeles Abrasion

Coarse aggregate shall be tested in accordance with AASHTO T 96.

1002.5.2.5 Deleterious Content

The percentage of deleterious substances for coarse aggregate is to be determined according to MoDOT TM-71, Deleterious Content of Aggregate. Where field determinations show a total deleterious content of 2.5 percent or less, including not more than 0.5 percent shale, the deleterious content is to be inspected visually. The sample is to be tested if visual inspection indicates more than 2.5 percent deleterious material present in the sample. Source approval samples shall always be tested regardless of the content of deleterious material.

The percentage of lightweight particles in fine aggregate is to be determined according to AASHTO T113 using a solution of zinc chloride and water. The heavy liquid shall have a specific gravity of 2.00 ± 0.01 at the beginning of the test and shall be maintained within that range during the test.

The other deleterious substances, clay lumps, and shale in fine aggregate shall be visually determined and separated into the constituents required by the applicable specification when an examination of the sample prepared for sieve analysis indicates a need for exact determination of deleterious content. Percentages shall be calculated as follows:

${\displaystyle P={\frac {100c}{W}}}$

where:

P=Percent of deleterious material

W=Weight of test sample and

c=Actual weight of deleterious material

1002.5.3 Sample Record

The sample record shall be completed in SiteManager, as described in Automation Section 3510, and shall indicate acceptance, qualified acceptance, or rejection. Appropriate remarks, as described in EPG 106.20 Reporting, are to be included in the remarks to clarify conditions of acceptance or rejection. Test results shall be reported on the appropriate templates under the Tests tab.