不排水抗剪强度与初始超固结比OCR的关系可以由三轴压缩状态下的不排水抗剪强度公式表示.首先根据该公式由强度试验数据计算土体各点OCR与其深度的关系式；然后将该关系式引入到UH模型有限元程序中；最后应用UH模型的有限元程序分别对考虑OCR随深度变化和OCR为1的不排水地基进行了数值分析,并对两种情况下的载荷—沉降曲线、随时间变化的地基表面沉降、随时间变化的结点剪应变、体应变和孔压曲线作了比较.分析可知:采用OCR随深度变化的UH模型的有限元程序能够合理考虑地基土体实际的超固结比,在非均质不排水地基的有限元分析中是有必要的.%The relationship between the undrained shear strength and the initial over consolidation ratio (OCR) can be expressed by the formulation of undrained shear strength under triaxial compression condition. Firstly, the relationship between OCR of soil and depth is obtained by using the test data of undrained shear strength according to the formulation. Then the relationship between OCR and depth is introduced to the finite element program of UH model, so the OCR changes with depth can be considered. Finally, the numerical analyses of undrained soil foundation considering OCR changes with depth and normally consolidated soil are performed respectively by using the finite element program of UH model. The load-settlement curves, the settling curves on center of foundation surface with time, the shear strain curves, volumetric strain curves and pore pressure curves for points with time under the two conditions are compared. The comparisons of results show that the finite element program of UH model considering OCR changes with depth can give the actual OCR of foundation soil reasonably, and it is necessary to be used in the finite element analysis of non-homogenous undrained soil foundation.
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