(1. State Key laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. Zhejiang Design Institute of Water Conservancy and Hydroelectric Power，Hangzhou，Zhejiang 310002，China)
Abstract：Coarse aggregate multi-scale study is mainly to establish the connection between fabric，contact forces，branch vector and constitutive relation，through probability statistics method for the direction and magnitude of the coarse aggregate orientational tensor. It gets a certain number of unit vector directional of contact probability distribution density function(fabric) and moment tensor by the method of statistical probability. The fabric tensor spread out three different forms polynomial expressions using least-square method to determine correlation coefficients. Three types of fabric tensor and the known data expression of statistics the relationship are set up. Orthogonal decomposition is used to make expansion independent with each other. Coarse aggregate stress expressions which included microstructure parameters fabric，contact force and branch vector are built. Compared with steel balls triaxial test and numerical calculation contrast macro-mesoscopic stress，two results are consistent. The simulation results indicate that second-rank contact normal density distribution function give reasonable approximations. A theoretical basis has been established for numerical simulation and the stress expressions for coarse aggregate microscopic parameters under the condition of three dimensional stress-contact force-fabrics.
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2014, Vol. 33 
