孔隙水压力对锯齿状结构面剪切蠕变特性的影响

为探究孔隙水压对岩体结构面剪切蠕变特性的影响，自主研制了结构面一体化制作模具和多功能剪切流变仪，开展了孔隙水压力下锯齿状结构面的剪切蠕变试验，分析了孔隙水压对结构面蠕变变形、蠕变速率和长期强度的影响。试验结果表明：不同孔隙水压力下的结构面先后经历了瞬时变形阶段、减速蠕变阶段和稳定蠕变阶段，并且孔隙水压力的增大促进了结构面非线性特征的发展；随着孔隙水压力的增大，结构面瞬时位移、蠕变位移和稳态蠕变速率逐渐增大，而蠕变时长、破坏应力和长期强度均呈现明显降低的趋势。根据试验结果，考虑孔隙水压力对模型参数的影响，将蠕变模型中的瞬时剪切模量、黏性剪切模量以及黏性系数替换为孔隙水压力的函数，构建了能够反映孔隙水压力影响的结构面蠕变模型，并对模型参数进行辨识，将试验曲线和理论模型曲线进行对比，验证了模型的正确性和适用性。研究成果对富水区岩体长期稳定性分析提供一定的理论指导。

Effect of pore water pressure on shear creep characteristics of serrate structural plane

To explore the effect of pore water pressure on shear creep characteristics of rock mass structural planes, an integrated die for fabricating structural planes and a JAW-600 multifunctional shear rheometer were independently developed. The shear creep tests were carried out on serrated structural planes under pore water pressure. The effects of pore water pressure on creep deformation characteristics, creep rate and long-term strength of structural planes were analyzed. The experimental results show that the structural planes under different pore water pressures have experienced instantaneous deformation, deceleration creep and steady creep stages successively, and the increase of pore water pressure promotes the development of the non-linear characteristics of the structural planes; the instantaneous displacement, creep displacement and steady creep rate of the structural planes gradually increase with the increase of pore water pressure, while the creep time, failure stress and long-term strength decrease with the increase of creep strength. According to the test results, considering the influence of pore water pressure on the model parameters, the instantaneous shear modulus, viscous shear modulus and viscous coefficient in the creep model are replaced by the function of pore water pressure, and a structural plane creep model reflecting the influence of pore water pressure is constructed. The model parameters are identified by the optimization analysis software, and the correctness and applicability of the model are verified by comparing the creep test curve with the theoretical model fitting curve. The research results provide some theoretical guidance for the long-term stability analysis of rock mass under the action of groundwater.