A nonlinear elastic model considering nonlinear soil behavior and the hysteresis loop at small strains was proposed to accurately estimate the deformation of earth retaining structures and the surrounding ground. A method of determining the input parameters for the proposed nonlinear model was established. We performed various laboratory and in-situ tests to estimate the normalized elastic modulus curve representing ground deformation characteristics with field ground strain, and we determined the constant R, C using the curve representing the nonlinearity of the proposed model. Further, a method of calculating the constant K and confining pressure exponent n by using the results obtained from the resonant column test and the triaxial test with varying the confining pressure was established to embody a confining pressure reduction due to ground excavation.
We investigated the applicability of the proposed nonlinear elastic model in field excavation by applying the above described input parameter determining method and the proposed nonlinear elastic model in three excavation. The numerical analysis results obtained through use of the input parameters described here are consistent with the field measurements we obtained.
By comparing the lateral wall deflection, obtained by assuming the soil modulus is a linear elastic modulus at a certain strain, to the results obtained by using the proposed nonlinear model, we investigated whether the lateral wall deflection was similar to the results obtained by using a nonlinear soil modulus. We therefore determined whether a certain extent of soil stiffness influences lateral wall deflection.
