(1. College of Pipeline and Civil Engineering，China University of Petroleum(East China)，Qingdao，Shandong 266580，China；2. Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines，Northeastern University，Shenyang，Liaoning 110819，China；3. PowerChina Northwest Engineering Corporation Limited，Xi?an，Shaanxi 710065，China；4. Qingdao Fusion Bridgehead Development Co.，Ltd.，Qingdao，Shandong 266500，China)
Abstract：The dissociation of gas hydrate leads to the reduction of the bearing capacity of the interface between gas hydrate-bearing soil and mining well，resulting in discontinuous deformation such as dislocation and sliding，which directly affects the stability of the mining well. In order to study the weakening law of gas hydrate-bearing soil-mining well interface under dissociation conditions，based on the developed low-temperature and high-pressure gas hydrate generation and triaxial test equipment，shear tests of gas hydrate-bearing sand-mining well interface under dissociation conditions are carried out，and the statistical damage model of gas hydrate-bearing sand-mining well interface considering dissociation effect is constructed. As a result，the interface is in strain softening state before gas hydrate dissociation，and the shear strength and dilatancy increase with the increase of saturation. The interface is in strain hardening state after dissociation，and the shear strength increases with the increase of saturation，but the dilatancy is slightly affected by it. In addition，comparing with before dissociation，the shear strength，cohesion and dilatancy of the interface decreased after dissociation，showing significant weakening characteristics. Therefore，considering the strength of the interface finite micro cells obeys Mohr-Coulomb strength criterion and double-parameter Weibull random distribution，the interface statistical damage model which can better simulate the failure of gas hydrate-bearing sand-mining well interface caused by dissociation is established，the relationships of the parameters m and F0 in the model with gas hydrate saturation，effective confining pressure and dissociation are analyzed. The relevant results can promote the research on the basic theory and key technology of gas hydrate exploration and development.
张 玉1，2，陶子卓1，2，栾雅琳1，狄圣杰3，林 亮4. 分解条件下含可燃冰砂土–开采井界面弱化规律试验研究[J]. 岩石力学与工程学报, 2024, 43(S2): 3988-3999.
ZHANG Yu1，2，TAO Zizhuo1，2，LUAN Yalin1，DI Shengjie3，LIN Liang4. Experimental study on the weakening law of gas hydrate-bearing sand-mining well interface under dissociation condition. , 2024, 43(S2): 3988-3999.
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2024, Vol. 43 
