I have a question on calculating the increase in stress under square foundation, when soil are layered. In Das' Foundation of geotechnical engineering ', Sec 7.12, there is an equation, delta(sigma)average=(delta(sigma)top+4*delta(sigma)mid+delta(sigma)bottom)/6
In another similar problem, the solution use Westergaard chart DM7.1-176 for layed soils. Using the two methods to solve the same problem I got different answers. Can someone tell me what's the difference between these methods, and when to use what if the problem didnot specify. Thanks.
In another similar problem, the solution use Westergaard chart DM7.1-176 for layed soils. Using the two methods to solve the same problem I got different answers. Can someone tell me what's the difference between these methods, and when to use what if the problem didnot specify. Thanks.