软土中T型触探仪贯入阻力的数值模拟

T型触探仪近年来在国外的海洋软土地基原位测试中得到了广泛应用，但贯入速率、地基土强度的各向异性与渐进软化等因素对于贯入阻力的影响没有得到系统的研究。在大型有限元软件ABAQUS平台上进行二次开发，针对基于Tresca屈服准则的理想弹塑性模型进行了相应改进，使之可以比较合理地反映上述因素的影响，进而对软土中T型触探仪的贯入机制进行了比较系统的数值分析。计算结果表明，贯入速率、地基土强度的各向异性与强度软化效应对于T型触探仪的贯入阻力系数影响较大。通过与有关极限分析上限解的对比分析，在一定程度上验证了有限元分析结果的合理性。

Numerical simulation of penetration resistance of T-bar penetrometer in soft clay

As a novel version of penetrometer, T-bar is extensively utilized in in-situ measurement for undrained shear strength of marine soft foundation. However, the effects of penetration velocity, anisotropy of soil strength and gradual softening on penetration resistance of T-bar penetrometer are seldom systematically investigated. The simple elastic-perfectly plastic Tresca model is modified to allow for the above mentioned effects based on the finite element software ABAQUS. Then the numerical simulations for penetration resistance mechanism of T-bar penetrometer in soft clay are conducted. The results show that the effects of strain rate, anisotropy of soil strength and strain softening on T-bar factor are appreciably large. Compared with the upper bound limit analysis, the present finite element solution is validated.