Evaluation of a simplified small-strain soil model for analysis of excavation-induced movements

A simplified small-strain soil model, referred to herein as the modified pseudoplasticity (MPP) model, developed based on the small-strain behavior of clay measured from the triaxial tests is evaluated in this study. The simulation of the small-strain triaxial tests by the MPP model shows that nonlinear stress–strain characteristics of clays can be adequately accounted for at small strain, including the characteristic of high initial Young's modulus. Two well-documented excavation case histories are used to assess the MPP model. Satisfactory predictions are obtained of the excavation-induced wall deflection and ground surface settlement by finite element method (FEM) that incorporates the MPP model. The lateral soil deformation behind the wall can also be reasonably predicted. The simplified MPP model is shown to be effective for modeling the excavation-induced wall and ground movements.Key words: braced excavation, wall deflection, ground settlement, finite element method, stress-strain relationship, cas...

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