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| Effect of block form on the shear marco- and meso-mechanical behaviors of S-RM based on 3D novel modelling approach |
| ZHANG Han1，2，XIANG Guoliang1，2，WANG Lehua1，2，DENG Huafeng1，2，ZHAO Erping1，2 |
| (1. Hubei Key Laboratory of Disaster Prevention and Mitigation，China Three Gorges University，Yichang，Hubei 443002，China；
2. College of Civil Engineering and Architecture，China Three Gorges University，Yichang，Hubei 443002，China)
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Abstract In order to study the effect of block form on the shear mechanical behaviors of the soil-rock mixture(S-RM)，a novel 3D block geometry modelling approach is proposed on the basis of CT technology and spherical harmonic series，for generating blocks with different forms(spheroidal，prolate，oblate and blade) but same convexity and angularity. Based on the improved non-overlapping cluster generation method，the 3D DEM block models，characterized by a higher computational efficiency，are established. The numerical direct shear tests were performed on S-RM models with different block shapes and breakable characteristics. The maro- and meso- mechanical properties of S-RM were deeply analyzed and the effect mechanism of block form was revealed. The results show that the occlusion，sliding friction degree and rotation magnitude of the spheroidal and prolate blocks are larger than those of the oblate and blade ones. The breakage of block increases the degree of block occlusion and rotation，but reduces its sliding friction degree. Under the combined effect of sliding friction and rotation of blocks，the breakage degrees of spheroidal blocks are the largest while the blade ones are the smallest，and the shear strength and dilation of S-RM with spheroidal and prolate blocks are larger than those with oblate and blade ones. Due to the breakage degrees of the spheroidal and oblate blocks are larger，the S-RM nonlinear characteristics of strength are more obvious than those of the S-RM with prolate and blade blocks. Due to the occlusion degrees of the spheroidal and prolate blocks are larger，the peak frictional angles of S-RM are larger than those of the S-RM with oblate and blade blocks.
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2022, Vol. 41 
