Research on coupling model of single fracture seepage and normal stress #br#
of rock mass considering the soft and hard aperture
YANG Jianhang1，2，YE Zuyang1，2，HUANG Shibing1，2，CHENG Aiping1，2
(1. School of Resource and Environmental Engineering，Wuhan University of Science and Technology，Wuhan，Hubei 430081，China；2. Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgical Mineral Resources，
Wuhan，Hubei 430081，China)
Abstract：The coupling mechanism of rock mass fracture seepage and normal stress is an important basis for hydro-mechanical coupling analysis of fractured rock mass. The normal stress and permeability curves of rock mass fracture often show nonlinear characteristics，and there is a significant difference with the increase of normal stress：the fracture permeability decreases sharply under low stress conditions，while the fracture permeability decreases slowly under high stress conditions. At present，traditional mathematical models can not describe the difference of fracture permeability under low stress and high stress. Therefore，based on two-part Hooke?s Model(TPHM)，the fracture closure is divided into two parts：the hard closure and the soft closure. The influence of the soft closure and the hard closure on the deformation and seepage characteristics of rock mass fracture under low stress and high stress conditions is considered respectively，and the coupling mathematical equation of rock mass fracture seepage and normal stress is established. Three groups of hydro-mechanical coupling test data under loading condition of granite fractures were used to verify the theoretical model. The results show that the theoretical model is basically consistent with the experimental data，and better than the negative exponential model，power function model and logarithmic model，indicating the effectiveness of soft and hard aperture in quantitatively describing the nonlinear hydro-mechanical coupling characteristics of rock mass fractures. The main control effect of soft aperture on rock fracture permeability under low stress state is revealed.
杨健航1，2，叶祖洋1，2，黄诗冰1，2，程爱平1，2. 考虑软体和硬体开度的岩体单裂隙渗流与法向应力耦合模型研究[J]. 岩石力学与工程学报, 2023, 42(S1): 3473-3480.
YANG Jianhang1，2，YE Zuyang1，2，HUANG Shibing1，2，CHENG Aiping1，2. Research on coupling model of single fracture seepage and normal stress #br#
of rock mass considering the soft and hard aperture. , 2023, 42(S1): 3473-3480.
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2023, Vol. 42 
