Sponsored by ASCE Continuing Education and the Geo-Institute (G-I).  

Instructor:  Jean-Louis Briaud, Ph.D., P.E., BC.GE, Dist.M.ASCE

Course Length:  90 minutes

Purpose and Background

The damage to houses built on shrink swell soils has been reported as being the most expensive disaster in the USA ahead of floods, hurricanes and earthquakes. While nobody dies, the structure deforms and cracks and the repairs can be very expensive. The best solution is to design a foundation which is stiff enough that the soil can deform while the deformation of the structure is limited to an acceptable level. In addition to this certain measures including good drainage will minimize the soil movement.

There are several types of foundation which are commonly used, some are good and some are bad. The good ones include the stiffened slab on grade for lighter structures and the elevated structural slab on piles for taller structures. The bad ones include the slab on grade and on piles and the thin flexible slabs. The stiffened slab on grade is the most economical foundation solution for houses on shrink swell soils.

This webinar presents a new design method developed at Texas A&M University over the last 15 years for stiffened slabs on grade. It includes the methodology to arrive at the final method, the design charts and how to use them, an example foundation design, a monitored case history, and an Excel spreadsheet to automate the design process. Participants will receive the Excel spreadsheet as part of the webinar.

Primary Discussion Topics

• Houses on shrink swell soils
• Shrink swell soils behavior
• House foundations solutions
• Design example
• Case history
• Dos and Don'ts for good house maintenance

Learning Outcomes

Upon completion of this course, you will be able to:

• Explain the behavior of shrink swell soils
• Identify the good and bad options for house foundations
• Describe what the proper objective of a foundation on shrink swell soils must be
• Determine how to properly design a stiffened slab on grade

Webinar Benefits

• Find out why houses on shrink swell soils crack
• Find out what are the good and bad solutions for foundations of houses on shrink swell soils
• Avoid costly errors in choosing foundations for houses on shrink swell soils
• Examine the results of a full scale case history
• Learn a new simple approach for the design of stiffened slab on grade
• Learn the dos and don'ts of house maintenance to minimize damage of houses on shrink swell soils
• Obtain a spread sheet to automate the new method