AASHTO T 258-81 (2018) PDF Download

The AASHTO T 258-81 (2018) standard is designed to provide a method for determining whether a soil is expansive and to predict the amount of swell that may occur. The standard acknowledges that there are various methods used by different agencies to control and mitigate the effects of swell, which are included in the appendix.

Expansive soils can cause significant damage to structures and infrastructure, as they have the ability to absorb and release moisture, leading to changes in volume and subsequent movement. This standard provides a framework for identifying and classifying soils based on their expansive characteristics.

By following the procedures outlined in this standard, engineers and geotechnical professionals can assess the expansive nature of a soil sample and make informed decisions regarding site suitability and foundation design. The inclusion of methods used by different agencies in the appendix further enhances the applicability and practicality of this standard.