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(Solved): A foundation is planned on a sand layer of friction angle \phi =30\deg and negligible cohe- sion. Th ...
A foundation is planned on a sand layer of friction angle \phi =30\deg and negligible cohe-
sion. The width of the footing is b and the footing will be at a depth D_(f)=0.2b below
ground level. A clay layer exists of thickness 3b with its upper boundary at a depth
Figure 2: A foundation on sand above a clay layer
of 1.6b below the base of the foundation. You may assume that the foundation load is
spread out at depth d over a width equal to b+d.
Question:
Determine (an) expression(s) for the total load that the foundation can bear in terms of
the width of the footing, the unit weight of the sand, \gamma _(s), the unit weight of the clay, \gamma _(c),
the friction angle of the sand, \phi , and the cohesion of the clay, c. Consider the clay to
be undrained, so that its friction angle is zero.