A MESO-MECHANICAL COUPLING CONSTITUTIVE MODEL OF DAMAGE AND PERMEABILITY IN ROCK-LIKE MATERIALS UNDER TRIAXIAL COMPRESSION
CAO Linwei1，PENG Xianghe1，YANG Chunhe2，REN Zhongjun3
(1. Department of Engineering Mechanics，Chongqing University，Chongqing 400044，China；2. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；3. School of Civil Engineering，Hunan University of Science and Technology，Xiangtan，Hunan 411201，China)
Abstract：Microcracks and microvoids are the main microdefects in rock-like materials. When water infiltrates into microcracks，an additional opening stress will be caused on the surface of microcrack. Based on superposition principle，the response characteristics of these rock-like materials which need to consider the water pressure in microcracks under triaxial compression are separated. Considering the deformation，extension and kink of elliptical microcracks in infinite deep buried rock under the condition far field 3D compressive stress，the additional flexibility tensor caused by single closure elliptical microcracks and kink microcracks on any space orientation in a RVE(representative volume element) is obtained. With the assumption that the permeability of the RVE is mainly up to the variation of kink microcrack extension on normal direction under triaxial compression，and making use of the Darcy¢s law and cubic law of laminar flow，the expression of additional permeability tensor of single kink microcrack is derived. Considering the effect of microcrack system on the deformation and permeability of RVE by Taylor¢s scheme，a 3D meso-mechanical coupling constitutive model of damage and permeability in rock-like materials under triaxial compression is obtained by probability density function. The numerical calculation shows that the calculations of this model agrees well with that of test.
曹林卫，彭向和，杨春和，任中俊. 三轴压缩下岩石类材料的细观损伤–渗流耦合本构模型[J]. 岩石力学与工程学报, 2009, 28(11): 2309-2319.
CAO Linwei1，PENG Xianghe1，YANG Chunhe2，REN Zhongjun3. A MESO-MECHANICAL COUPLING CONSTITUTIVE MODEL OF DAMAGE AND PERMEABILITY IN ROCK-LIKE MATERIALS UNDER TRIAXIAL COMPRESSION. , 2009, 28(11): 2309-2319.
