wwen
Geotechnical
- Mar 6, 2018
- 5
Hi All,
We are currently trying to analyze two layer bearing resistance of a footing using the method listed in AASHTO LRFD 7th Ed C10.6.3.1.2f-1 and Meyerhof and Hanna (1980).
The words in AASHTO say that for q2 the resistance is to be taken for a "fictitious footing of the same size and shape as the actual footing but supported on surface of the second (lower) layer of a two-layer system". If we assume a embedment of 4 ft, does that mean that the Df for q1 and q2 are 4 ft or does it assume that Df for q1 is 4 feet and the Df for q2 is 4 ft + (thickness of layer 1-embedment)?
Also, for the Meyerhof and Hanna method - are we supposed to assume effective unit weight of soil for saturated soils below the GWT? The references I have on hand are not explicit with regards to this.
Thank you.
We are currently trying to analyze two layer bearing resistance of a footing using the method listed in AASHTO LRFD 7th Ed C10.6.3.1.2f-1 and Meyerhof and Hanna (1980).
The words in AASHTO say that for q2 the resistance is to be taken for a "fictitious footing of the same size and shape as the actual footing but supported on surface of the second (lower) layer of a two-layer system". If we assume a embedment of 4 ft, does that mean that the Df for q1 and q2 are 4 ft or does it assume that Df for q1 is 4 feet and the Df for q2 is 4 ft + (thickness of layer 1-embedment)?
Also, for the Meyerhof and Hanna method - are we supposed to assume effective unit weight of soil for saturated soils below the GWT? The references I have on hand are not explicit with regards to this.
Thank you.