SEEPAGE BENEATH WATER RETAINING STRUCTURES FOUNDED ON SPATIALLY RANDOM SOIL

The effect of stochastic soil permeability on confined seepage beneath water retaining structures has been studied. Random field concepts fo r the generation of soil permeability properties with a fixed mean, st andard deviation and spatial correlation structure have been combined with finite element methods to perform Monte Carlo simulations of the seepage problem. Analyses have been performed for a dam with two cut-o ff walls. The results of parametric studies to gauge the effect of the standard deviation and correlation structure of the permeability on t he output statistics relating to seepage quantities, exit gradients an d uplift pressures are presented. In all cases, comparison is made wit h results that would be achieved on a deterministic basis. Flow rates and other quantities are shown to be affected significantly by the sta ndard deviation and the correlation structure of soil permeability.