Computational techniques and shear band development for cylindrical and spherical penetrometers in strain-softening clay
Computational techniques and shear band development for cylindrical and spherical penetrometers in strain-softening clay
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DOI：
10.1061/(asce)1532-3641(2007)7:4(287
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发表时间：
2007-07
影响因子：
3.7
通讯作者：
Hongjie Zhou;M. Randolph
中科院分区：
文献类型：
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作者：
Hongjie Zhou;M. Randolph
本文讨论了应变软化、速率相关的粘性土中全流量流量计深穿透的数值模拟，以及观察到的周期性剪切带现象。分析采用大变形有限元法，修改简单的弹性-理想塑性Tresca土壤模型，允许应变软化，应变率依赖性被纳入，以避免虚假的网格依赖性。参数分析进行了不同的应变软化参数（因此土壤的相对脆性），土壤的刚度指数，和应变率参数。土壤的脆性增加导致的贯入阻力减少，但也越来越显着的电阻贯入响应的振荡。振荡被认为是由于周期性的剪切带周期性地发展前进的圆柱形和球形的流速计。不同刚度指标的分析证实了这一结论。
This paper addresses numerical simulation of deep penetration of full-flow penetrometers in strain-softening, rate-dependent, cohesive soil, and the observed phenomenon of periodic shear bands. The analysis was conducted using a large deformation finite element approach, modifying the simple elastic–perfectly plastic Tresca soil model to allow strain-softening, with strain-rate dependency being incorporated in order to avoid spurious mesh dependency. Parametric analyses were carried out varying the strain-softening parameters (hence the relative brittleness of the soil), the rigidity index of the soil, and the strain-rate parameter. Increased brittleness of the soil led to reduction in the penetration resistance, but also to increasingly significant oscillations in the resistance–penetration responses. The oscillation was found to result from periodic shear bands evolving cyclically ahead of the advancing cylindrical and spherical penetrometers. Analyses with different values of rigidity index confirmed f...