Micro-Deformation Mechanism of Shear Banding Process Based on Modified Distinct Element Method
Micro-Deformation Mechanism of Shear Banding Process Based on Modified Distinct Element Method
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DOI：
10.1016/s0032-5910(99)00236-3
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发表时间：
1999-08
影响因子：
5.2
通讯作者：
K. Iwashita;M. Oda
中科院分区：
文献类型：
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作者：
K. Iwashita;M. Oda
采用离散元法对剪切带的微观变形机制进行了数值模拟。为此，对传统的DEM进行了轻微修改，以便可以考虑接触点处滚动阻力的影响（称为MDEM）。它被发现，MDEM可以是一个强大的工具，不仅模拟剪切带内的大空隙的产生，但也高梯度的颗粒旋转沿着剪切带边界，在一个非常类似的方式在天然粒状土壤中观察到的。根据数值模拟试验结果，认为硬化过程中柱状组织的生成和软化过程中柱状组织的坍塌是导致剪切带形成的基本微观变形机制。
Numerical simulation tests were carried out using the distinct element method (DEM) by paying much attention to the micro-deformation mechanism leading to the development of shear bands. To do this, the conventional DEM was modified slightly such that the effect of rolling resistance at contact points could be taken into account (called MDEM). It is found that MDEM can be a powerful tool for simulating not only the generation of large voids inside a shear band but also the high gradient of particle rotation along the shear band boundaries, in a quite similar manner to those observed in natural granular soils. It is concluded, based on the numerical simulation tests, that the basic micro-deformation mechanism ending up with the formation of shear bands is in the generation of a column-like structure during the hardening process and its collapse in the softening process.