针对非均质软土地基上吸力式沉箱的抗拔极限承载力,运用大型有限元分析软件ABAQUS进行了三维非线性数值分析。通过一定数量的数值计算与分析,较系统地考察了沉箱承受拉拔荷载过程中主动侧土体与结构接触状态对沉箱极限承载力的影响。由此表明:软土地基的不排水抗剪强度、吸力式沉箱结构的长径比、荷载作用点位置等因素对于主动侧土体与结构的接触状态具有一定影响。通过与有关模型试验结果及极限分析上限解的对比分析,在一定程度上验证了有限元计算模型与数值分析结果的合理性。
The three-dimensional nonlinear numerical analysis of the ultimate pull-out resistance capacity of suction caissons in inhomogeneous soft clay was presented. The finite element software ABAQUS was utilized and numerical computations were conducted through the numerical analysis, and the effect of the contact state of the interface between the soil on the active side and the caisson upon the pull-out resistance of the caissons during its operation was studied. It was shown that the bonding or debonding conditions between the soil on the active side and the caissons were affected by the undrained shear strength of the soft subsoils, the aspect ratio of the caissons, the position of the attachment point and the inclination of the pull-out force. The rationality of the proposed numerical procedure based on FEM was validated by comparing the present solutions with experimental data and the results computed by the upper-bound limit analysis for a given model test.