Multivariate Adaptive Regression Splines Approach to Estimate Lateral Wall Deflection Profiles Caused by Braced Excavations in Clays

Abstract

Based on a database including a total of 30 case histories for braced excavation in stiff, medium and soft clays, a multivariate adaptive regression splines (MARS) approach for estimating wall deflection profile caused by deep braced excavations is presented in this study. For each soil type, ten case histories with information on subsurface soil conditions, geometry characteristics, excavation support system details, the maximum wall deflections and the wall deflection profile against embedded depth are provided. Seven input variables, including wall length, excavation depth, excavation length, system stiffness, average unit weight and undrained shear strength of the soil, and the depth below the ground surface, are adopted as inputs to the MARS deflection profile model. Comparison with three more excavation case histories indicates that the developed MARS model can give an accurate graphical representation of the wall deflection profile. It is capable of not only predicting the value of maximum wall deflection but also estimating the possible depth at which maximum lateral deformation occurs.