Macro- and micro-properties and formation mechanisms of granular piles
DAI Bei-bing1, YANG Jun2, LIU Feng-tao3, LIN Kai-rong1
1. School of Civil Engineering, Sun Yat-sen University, Guangzhou 510275, China;
2. Department of Civil Engineering, The University of Hong Kong, Hong Kong, China;
3. School of Earth Science and Engineering, Sun Yat-sen University, Guangzhou 512075, China
A DEM study is carried out to simulate the construction of granular piles by considering various particle shapes. The underlying mechanisms are analyzed through the examination of the macro and micro-characteristics of granular piles. It is found that angle of repose decreases as particle shape evolves towards a regular pattern. Microscopically, the anisotropy magnitudes of contact orientation vectors, contact normal and tangential force vectors decrease as particle shape evolves from an irregular one to a regular one. The summation of the angle difference Δ?n between the principal anisotropy direction of contact orientation vectors and the vertical direction, with the angle of repose α, is almost a constant, and the angel differences Δ?f and Δ?t for the principal anisotropy directions of contact normal and tangential forces are revealed to be a linear function of angle of repose α. In addition, a relationship is also established between the direction where the most intense arching effect occurs and the principal anisotropy directions of contact orientation vectors, contact normal and tangential force vectors.
戴北冰, 杨峻, 刘锋涛, 林凯荣. 散粒土自然堆积的宏细观特征与形成机制[J]. 岩土工程学报, 2019, 41(S2): 57-60.
DAI Bei-bing, YANG Jun, LIU Feng-tao, LIN Kai-rong. Macro- and micro-properties and formation mechanisms of granular piles. Chinese J. Geot. Eng., 2019, 41(S2): 57-60.
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