Simplified calculation method for the accumulated deformation of peaty soil under long-term cyclic loading
CHEN Cheng, ZHOU Zhengming, ZHANG Xianwei
1. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics,Chinese Academy of Sciences, Wuhan，Hubei 430071, China
Abstract：The cumulative deformation of subsoil is more cared than the deformation raised during every cycle when predicting the deformation of soft ground subjected to traffic loading.Considering that the development of cumulative deformation of soil subjected to cyclic loading is similar to the creep under static loading, the number of loading cycles was equivalent to a time measuremeut unit.Based on the critical state theory, a simplified method for calculating the 3D cyclic cumulative deformation of soil was established by introducing a creep potential function and utilizing the empirical model for the cyclic cumulative axial strain in typical undrained cyclic triaxial tests.Then, a numerical scheme for the proposed model was proposed based on an implicit stress integration algorithm.It was implemented by compiling a UMAT subroutine and utilizing the user-defined material model in the commercial FEM software ABAQUS.Finally, a series of undrained cyclic triaxial compression tests and the long-term settlement of peaty soil under subway loading were simulated by the proposed simplified method, which validates the rationality and stability of the numerical model.
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