The minimum density target must meet which standard?

The minimum density target must meet which standard?

• A. FM 1 T-180
• B. ASTM D1557
• C. AASHTO T99
• D. AASHTO T190

Answer: (A)

The main idea is understanding where field compaction targets come from. In field earthwork, the minimum density target and the method for verifying it are defined by a field acceptance standard that specifies how to measure in-place density and what density the project must meet. FM 1-T180 is the field standard used for this purpose in highway construction. It lays out the target density and the acceptable range, and it describes the field testing methods (such as using a nuclear gauge or a sand cone) to verify that target is met. The other standards are primarily lab-oriented or describe measurement methods rather than setting the field acceptance target. ASTM D1557 is a laboratory compaction test that provides a relationship between moisture and density and is used to determine maximum dry density and optimum moisture in the lab. AASHTO T99 is another lab-based compaction test, and AASHTO T190 covers density measurement by nuclear methods but is not the standard that fixes the field minimum density target.

The main idea is understanding where field compaction targets come from. In field earthwork, the minimum density target and the method for verifying it are defined by a field acceptance standard that specifies how to measure in-place density and what density the project must meet. FM 1-T180 is the field standard used for this purpose in highway construction. It lays out the target density and the acceptable range, and it describes the field testing methods (such as using a nuclear gauge or a sand cone) to verify that target is met.

The other standards are primarily lab-oriented or describe measurement methods rather than setting the field acceptance target. ASTM D1557 is a laboratory compaction test that provides a relationship between moisture and density and is used to determine maximum dry density and optimum moisture in the lab. AASHTO T99 is another lab-based compaction test, and AASHTO T190 covers density measurement by nuclear methods but is not the standard that fixes the field minimum density target.