Question

The bearing capacity of a pad foundation can be calculated using the formula given by:

qf = cNcscic + gDNqsqiq + 0.5gBNgsgig

Consider a shallow foundation with dimensions equal to 3 m x 4 m. The foundation will need to be placed on soil found in-situ which is a firm, saturated clay (gsat = 19.5 kN/m3) layer extending to considerable depth with the following geotechnical properties:

c’ = 10 kPa

f = 35o

Assume that there is no ground water level observed from ground investigation reports.

a) What is the foundation depth required to achieve a minimum bearing capacity of 4500 kPa?

b) Assume that the ground water level is likely to raise up to the ground surface (due to heavy rain during winter). If the requirement of a minimum bearing capacity equal to 4500 kPa is maintained, what would be the minimum area required for a square footing founded at the minimum depth found in part (a) for this new conditions during winter?

c) How would you expect this foundation to fail? Explain the reason for your comments.

d) Briefly explain three (3) different methods that can be used to increase bearing capacity in soils.

(

Answer 1