QUESTION
What is the difference between a slab on grade and a mat foundation?
REPLIES
Ron
Slabs on grade are very lightly loaded. They are typically unreinforced or lightly reinforced for crack control. Mat foundations are intended to support heavy column loads and are intended to “throw the loads” lower into the soil profile but at lower stress levels because of the large area. This reduces settlement and decreases the potential for isolated bearing capacity failures of individual footings.
SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=456931
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