Reliability-Based Design of Laterally Loaded Piles Considering Soil Spatial Variability

Abstract

The p-y method has been commonly used for analysis of laterally loaded piles. Recently, a sampling-based approach for reliability analysis of laterally loaded piles has been developed by the authors. With the performance criteria defined for the laterally loaded piles, the probability of non-satisfactory performance can be conveniently computed. However, at any project site, soil properties used as input in the computation, such as strength parameters and stiffness values, generally exhibit spatial variations. There is a need to take into account of this spatial variation in the reliability analysis. In this paper, the Monte Carlo simulation technique developed for reliability analysis of laterally loaded piles is briefly described first. Next, a statistical tool for taking into consideration of spatial variability of pertinent soil properties in the developed reliability analysis is presented. A design example is given to illustrate the influences of spatial variability of soil properties on the computed outcome. Specifically, the correlation length of the soil properties at the site can exert significant influences on the computed results. It is recommended that spatial correlation of soil properties should be considered in order to accurately perform reliability analysis and design of piles under lateral loads.