Estimating Basal‐Heave Stability for Braced Excavations in Soft Clay

Abstract

The basal stability of braced excavation systems in soft clay has been investigated using the finite‐element method. A linear elastic‐perfectly plastic relationship is used to model the stress‐strain behavior of the soil. The important factors affecting basal stability have been identified as the thickness of the clay layer beneath the bottom of the excavation, the depth of the wall below the bottom of the excavation, the width/height ratio of the excavation, and the stiffness of the wall. From the results of parametric studies, a simple procedure is proposed for estimating basal‐heave stability. Charts are presented that can be used to estimate basal‐heave stability quickly and reliably.