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| NUMERICAL SIMULATION OF HYDRO-MECHANICAL COUPLING AND SOLUTE TRANSPORT IN COMPLEX FRACTURED ROCK MASSES |
| YAO Chi1，2，JIANG Qinghui1，2，WEI Wei1，ZHOU Chuangbing1，2 |
(1. School of Civil and Architectural Engineering，Wuhan University，Wuhan，Hubei 430072，China；2. State Key Laboratory
of Water Resources and Hydropower Engineering Science，Wuhan University，Wuhan，Hubei 430072，China) |
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Abstract To realistically reflect changes in fracture aperture under complex stress conditions，a non-linear fracture constitutive model is introduced into rigid body spring model，taking into account the non-linear normal stress and deformation relationship，tangential shear slip and dilation effects. Based on this method and combining a discrete fracture network model，an implicit hydro-mechanical coupling model is established. Since fractures are explicitly considered，evolution of fracture networks during coupling process can be accurately simulated. A particle tracking method is used to simulate solute transport in fracture network after converge of coupling process is obtained. Corresponding program is developed in accordance with the proposed model. An example from DECOVALEX project is analyzed to study the impact of different stress conditions on flow and solute transport. Key mechanism controlling the coupling processes is studied；and it?s found that under low stress ratio and high stress ratio conditions，coupling process are mainly controlled by normal stress displacement relation and dilation effects respectively. By comparative analysis，the validity of the proposed model is verified. The necessity of considering hydro-mechanical coupling effect under high water head condition is discussed.
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Received: 14 November 2012
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2013, Vol. 32 
