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| PARTICLE FLOW SIMULATION OF INFLUENCE OF PARTICLE SHAPE ON MECHANICAL PROPERTIES OF QUASI-SANDS |
| KONG Liang1，2，PENG Ren2 |
(1. School of Science，Qingdao Technological University，Qingdao，Shandong 266033，China；
2. School of Physics Electrical Information Engineering，Ningxia University，Yinchuan，Ningxia 750021，China) |
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Abstract Four particle groups with different outlines are generated by the command of clump in PFC2D. Combining with deformation mechanism of granular materials，a shape coefficient is defined based on roundness and unevenness. The shape coefficient and friction coefficient are used to reflect the characteristics of particle outline and surface roughness respectively. The particle stacking test，biaxial test and direct shear test have been simulated with PFC2D，and how the shape of the particles affect the macro-mechanical properties of granular materials has been discussed. The results show that particle shape plays an important role in the macro-mechanical properties of these tests. In the particle stacking test，the natural angle of repose and natural porosity increases with the irregular outline of particles and the friction coefficient between particles. In the biaxial test，peak strength and shape coefficient can be fitted with linear functions well，and the internal friction angle increases with the decrease of shape coefficient. In the direct shear test，the shear strength of materials increases with the decrease of shape coefficient；the irregularity of particle shape also results in the decrease of strong force chain and the inhomogeneity of velocity field.
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Received: 18 May 2011
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2011, Vol. 30 
