砂岩蠕变特性的水物理化学作用效应试验研究

 针对干燥、饱水以及不同离子浓度和酸碱度水溶液循环流动作用至水–岩反应平衡后的砂岩试件，完成一系列单轴压缩蠕变试验。根据试验结果，通过对不同应力水平下干燥砂岩和饱水砂岩的应变–时间关系、瞬时应变、蠕变应变及蠕变速率的比较分析，揭示饱水砂岩蠕变特性的水物理作用效应与机制。在此基础上，分别针对砂岩在酸碱度相同而离子浓度不同以及酸碱度不同而离子浓度相同这两类流动水溶液作用后，其应变–时间关系、瞬时应变、蠕变应变及蠕变速率的差异性开展系统研究，获得砂岩蠕变特性的水溶液离子浓度影响效应和酸碱度影响效应，进而探讨其水物理化学作用机制。研究结果表明，饱水砂岩蠕变性质比干燥砂岩明显；上述不同流动水溶液作用后的砂岩蠕变特性又比干燥、饱水砂岩显著；饱水砂岩蠕变特性主要存在水物理作用效应；而不同流动水溶液作用后砂岩的蠕变特性则兼具水物理作用效应和水化学作用效应；砂岩蠕变的水溶液离子浓度作用效应呈现出离子浓度越高则蠕变特性越显著的特点。研究成果对于岩石流变力学及水–岩相互作用领域的理论与应用研究，具有良好的启示与借鉴意义。

EXPERIMENTAL RESEARCH ON CREEP BEHAVIOR AND MECHANISM OF SANDSTONES WITH HYDRO-PHYSICO-CHEMICAL EFFECTS

A series of uniaxial compression creep tests on dry，saturated sandstones，and the sandstones with hydro-physico-chemical influencing effects due to the circulating flow of different hydro-chemical solutions are conducted. Based on the test results，the strain versus time relations，instantaneous strains，creep strains and creep rates of dry and saturated sandstones under different stress levels are compared；and the hydro-physical influencing effects and mechanisms of saturated sandstone are derived. Furthermore，the differences of creep strain versus time relations，creep strains，instantaneous strains and creep rates of the sandstones with hydro-physico-chemical influencing effects due to the circulating flow of different hydro-chemical solutions are systematically and originally researched respectively. The influencing effects of ion concentrations and pH values of the different hydro-chemical solutions are revealed；and the corresponding mechanisms of hydro-physico-chemical actions are investigated. The research demonstrates that the creep behavior of saturated sandstone is more obvious than that of dry sandstone，while the creep behavior of the sandstones with hydro-physico-chemical influencing effects due to the circulating flow of different hydro-chemical solutions are larger than those of dry and saturated sandstones. The creep behavior of saturated sandstone is affected dominantly by the hydro-physical action. The creep behavior of the sandstones due to the circulating flow of different hydro-chemical solutions has both the hydro-physical and hydro-chemical influencing effects. The larger the creep behaviors of sandstones are，the stronger the ion concentrations of the hydro-chemical solutions are. This paper has a useful reference to the theoretical and applied research in the field of rock rheological mechanics and water-rock interaction.