Chapter 2: Materials

3.0 Sampling Binders and Aggregates

Each highway agency has guidelines for sampling materials. These material sampling guidelines should be followed to assure product quality.

3.1 Special Considerations for Emulsions

In the case of emulsions, sampling is a significant issue. Samples must be sent immediately for testing to ensure they are representative of the material used in the field.

Emulsions, as discussed earlier, change and coarsen with storage and handling. This may result in an emulsion that is out of specification when tested despite being in specification when sampled and used. This is especially true of high binder PMCRS-2 and 2h type materials.

3.2 General Testing Details

The following guidelines should be followed for sampling materials (20):

Samples of emulsion and binder shall be taken in conformance with the requirements in AASHTO T 40, “Sampling Bituminous Materials.”
Observe safety procedures.
Sample binders daily using new, clean, dry, 1-liter cans with screw lids.
Samples are normally taken from the application lance at the rear of the distributor. Drain off sufficient material through the nozzle to ensure removal of any material lodged there.
Samples should be taken after one-third and not more than two-thirds of the load has been removed.
Do not submerge sample containers in solvent or wipe containers with solvent saturated cloths. Immediately after sampling, clean containers using only a clean, dry cloth.
Attach a Sample Identification to each material sample.
Protect the printed specifications and construction procedures against moisture and stains.
Provide the e-mail address of the RE on the TL-0101.
Emulsions have a shelf life. It is important that all samples be sent to the Transportation Laboratory daily.
Aggregates should be sampled according to the contractual requirements.
Samples of aggregate shall be taken according to Section 39-3.03 “Proportioning” of the Standard Specifications.
Samples may be taken from a conveyor belt or sampling chute.
Field samples must be taken from the stockpile. AASHTO T 2 and Section 39 3.03 of the Standard Specifications (2) describe the method.

Send samples for testing to the Transportation Laboratory:

Division of Materials Engineering and Testing Services
Flexible Pavement Materials Branch, MS #5
5900 Folsom Boulevard
Sacramento, California 95819-4612

Samples are not to be shipped C.O.D.
Emulsion will be tested for compliance with Section 94, “Asphaltic Emulsions”, of the Standard Specifications (2).
Aggregate samples should be tested for compliance with Section 39 “Asphalt Concrete” or Section 37 “Seal Coats” of the Standard Specifications (2) as appropriate.
Test results are mailed to Resident Engineers. To expedite return of test results, test cards can be e-mailed to the Resident Engineers, if an e-mail address is provided on the TL-0101.