Probabilistic analysis of strip footings resting on soil with uncertain properties

Abstract

ABSTRACT The safety level of geotechnical problems has long been taken into account via a global safety factor (Fs). The role of this factor is to globally overcome the risks related to possible errors that may arise during field or laboratory tests. Indeed, there is no scientific basis for suggesting the value of Fs. For most geotechnical problems, it is suggested to take a safety factor of 3. This suggestion is arbitrary and does not take into account the circumstances of the problem under consideration. In the present paper, a more efficient approach to evaluate the safety level of geotechnical problems is employed. This is the probabilistic approach. This approach allows taking into consideration the uncertainty of soil properties arises from possible sources of errors. In the probabilistic approach, the safety level of geotechnical problems is expressed by means of the probability of failure (Pf). Several probabilistic methods to compute the Pf value can be found in literature. In the present paper, a robust and accurate method called Monte Carlo Simulation (MCS) is employed to present a probabilistic analysis of a strip footing resting on a clayey sand soil with uncertain soil properties.