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| Meso-mechanics of soil-rock mixture with real shape of rock blocks based on 3D numerical direct shear test |
| XU Wenjie1，2，WANG Shi2 |
| (1. Key Laboratory of Failure Mechanism and Safety Control Techniques of Earth-rock Dam of the Ministry of Water Resurces，NHRI，Nanjing，Jiangsu 210024，China；2. State Key Laboratory of Hydroscience and Hydraulic Engineering，Tsinghua University，Beijing 100084，China) |
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Abstract The shape of the rock block influence greatly the meso-structure and macro-meso mechanical behaviour of soil-rock mixture(S-RM). In this paper，a method for the study of meso-mechanics of S-RM based on the real shape of rock blocks was presented. Firstly，the database of 3D geometric model of rock blocks was built based on 3D scanning technology. Then，with the database and the block size distribution，a special 3D model of S-RM with rock blocks was generated. A numerical model of S-RM sample was also generated. Furthermore，using the proposed multi-sphere modelling method of complex blocks，arbitrary particles can be modelled with the multi-spheres contacted uniformly and closely. As a result，a 3D DEM meso-structural model of S-RM sample was generated. In accordance with the field test，a series of 3D numerical direct shear tests were carried out. The meso-mechanical parameters of the soil particles used in the DEM numerical test were obtained from the field tests. The results of numerical tests indicated that the rock blocks made the shear zone of the S-RM sample wider and more zigzag than that of the soil sample，which induced the higher friction angle of the former. However， with the increase of the rock block content，the content of the fine soil particles with binding function decreased. As a result，the cohesion of S-RM was smaller than that of the soil sample.
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2016, Vol. 35 
