路基固结性状的非保守大变形有限元分析

Non-conservative Large-strain Finite Element Analysis of Roadbed Consolidation Behavior

针对传统方法存在保守荷载假设的局限性,考虑路基固结过程中实际体力的非保守特点,提出了路基平面应变固结性状分析的非保守大变形有限元法;并利用该方法对填土分级堆载作用下软土路基固结性状进行了算例分析。结果表明:当忽略体力的非保守性质时,非保守方法可以退化为传统方法;传统方法预测的路基平面应变固结沉降量、侧向位移值和超静孔压等一般均大于非保守方法的分析结果;非保守大变形有限元法可以有效提高路基平面应变固结变形的预测精度,尤其对于路基变形较大的情况更是如此。

Aimed at limitations of the hypothesis of conservative load in traditional roadbed consolidation analysis, considering the non conservative property of body force during roadbed consolidation process, a non-conservative large-strain finite element method for the analysis of roadbed plane-strain consolidation behavior was presented. The analysis of an illustrative example of soft clay roadbed consolidation behavior under embankment-fill step-loading was done by the method. Results show that when ignoring the non-conservative property of body force, the nonconservative method can reduce to traditional method correspondingly. The values of roadbed plane-strain consolidation settlement, lateral displacement and excess pore water pressure calculated by traditional method will be larger than those calculated by the presented method in most cases. The non-conservative large-strain finite element method can effectively improve the prediction precision of roadbed plane-strain consolidation behavior, especially for the cases of roadbed large deformation.