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
Students' achievement of the learning outcomes will be assessed via a short post-assessment (true-false, multiple choice and fill in the blank questions).
Intended Audience
- Geotechnical engineers
- Structural engineers
- Geologists
- Building inspectors
- City engineers
Webinar Outline
- Behavior of houses on shrink swell soils
- Why do soils shrink and swell
- The three zones of soils under a house
- Tests to measure the shrinking and swelling
- Typical house deformation
- Important design parameters
- Water tension also called suction
- Depth of the active zone
- Change in water content over the seasons
- The weather, the soil, the structure
- Development of the method
- Behavior of flexible covers on shrink swell soils
- Behavior of stiff slabs on unevenly deformed soil surface
- The soil weather index
- The design charts
- Application of the method
- Example design
- Dallas foundation tests
- College Station case history
- Use of the spreadsheet TAMU-SLAB escription to come
How to Earn your CEUs/PDHs and Receive Your Certificate of Completion
To receive your certificate of completion, you will need to complete a short on-line post-test and receive a passing score of 70% or higher within 1 year of purchasing the course.
How do I convert CEUs to PDHs?
1.0 CEU = 10 PDHs [Example: 0.1 CEU = 1 PDH]