AASHTO T 221-90 (2021) PDF Download

The AASHTO T 221-90 (2021) standard provides guidelines for conducting repetitive static plate load tests on subgrade soils and compacted pavement components. These tests can be performed on both the compacted condition and the natural state of the materials.

The purpose of this standard is to gather data that can be used in the evaluation and design of both rigid and flexible-type pavements for airports and highways. It aims to assess the load-bearing capacity and structural properties of the tested materials, which are crucial factors in pavement performance.

Moreover, it is worth noting that this method is technically equivalent to ASTM D 1195/D 1195M-09, which means that the testing procedures and requirements outlined in both standards are essentially the same. This equivalence ensures that the test results obtained from following either standard are reliable and consistent.