Reliability analysis of allowable pressure on shallow foundation using response surface method

The concept of response surface method (RSM) is used to generate approximate polynomial functions for ultimate bearing capacity and settlement of a shallow foundation resting on a cohesive frictional soil for a range of expected variation of input soil parameters. The response surface models are developed using available conventional equations and numerical analysis. Considering the variations in the input soil parameters, reliability analysis is performed using these response surface models to obtain an acceptable value of the allowable bearing pressure. The results of the reliability analysis are compared with the results of Monte Carlo simulation and it is demonstrated that application of response surface method in the probabilistic analysis can considerably reduce the computational efforts and memory requirements. It is also concluded that conventional analysis using available equations and numerical analysis when used in conjunction with reliability analysis enable a rational choice of allowable pressure and help in decision-making process.