Expansive Soils and Structural Foundations

February 19, 2022


Institutional projects (anticipated building lifecycle of 100+ years) on sites predominated by expansive clay soils, often elect to proceed with a structural foundation over a crawl space as depicted below.

These foundation systems come at a substantial first cost premium (typically 2 to 3 times that of a conventional on-grade foundation), however they pose substantially less risk of future issues and cost related to expansive soil movement.

Issues related to expansive soil related movement rarely manifest into structural integrity issues, however they can cause habitual cosmetic distress (cracks in drywall, brick/stone veneer, flooring, etc.) and functional distress (sticking doors, uneven floors, etc.) of which the cost to remediate can easily cost multiples of the original foundation cost.

The images below reflect one such crawl space and clearly exhibit the shrink/swell behavior of expansive clay soils. In this case, the subgrade soils are showing large dessication cracks which are common when expansive clay soil loses moisture.

DUDLEY has experts in both geotechnical and structural foundation engineering that help developers, owners and institutions navigate expansive soil issues and design cost effective solutions that are custom tailored for the needs of the project at hand.

If you expect expansive soils on your next development in Bryan, College Station, Waco, Houston, Dallas, Temple, Hunstville, Conroe, Killeen or pretty much anywhere in Texas, reach out to us at 979-777-0720.