ASTM D2940/D2940M-20 PDF Download

The ASTM D2940/D2940M-20 standard is a specification that outlines the requirements for graded aggregate material used as bases or subbases for highways or airports. The purpose of this standard is to ensure that the aggregates used provide adequate stability and load support when properly spread and compacted.

The standard specifies that the coarse aggregate used should consist of durable particles of crushed stone, gravel, or slag that can withstand handling, spreading, and compacting without degradation. The fine aggregate should typically be the fines generated from crushing the coarse aggregate, although the addition of natural sand or finer mineral matter is also allowed if suitable.

The standard also lists several tests that should be performed on the aggregates, including grain-size test, liquid limit test, plastic limit test, plasticity index test, sand equivalent value test, and expansion test. These tests are conducted to assess the quality and characteristics of the aggregates.

Additionally, the standard provides a note cautioning engineers to provide appropriate construction specifications to ensure proper compaction of the aggregates. It suggests using compaction on a control strip of the material to achieve a certain average density, with a minimum of 98% recommended for base courses.

It's important to note that the notes and footnotes included in the standard are for explanatory purposes and are not considered as requirements of the standard itself.