基于卸荷作用的深部围岩拉伸蠕变损伤演化机理及本构模型研究

项目名称： 基于卸荷作用的深部围岩拉伸蠕变损伤演化机理及本构模型研究

项目编号： No.41302223

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 赵宝云

作者单位： 重庆科技学院

项目金额： 27万元

中文摘要： 油气井的钻探与地下洞室的开挖对深部高地应力区的围岩是一个长期的卸荷过程，而卸荷过程中又往往伴随着拉应力的出现。由于岩石的抗拉强度仅为抗压强度的1/6-1/32，因而，传统沿用压缩参数的方法已不能满足解决深部围岩流变力学问题的需要。鉴于此，本项目将对深部油气工程中的页岩、砂岩以及深部地下洞室工程常见的大理岩等多种岩石展开室内直接拉伸蠕变试验、试样破裂面电镜扫描试验以及深部孔洞蠕变损伤相似模拟试验与数值模拟仿真试验。在试验研究的基础上，结合理论分析探索深部围岩拉伸蠕变损伤演化机理，揭示深部围岩拉伸蠕变细观破坏规律，探讨蠕变损伤函数关系，最终，建立一种深部岩体广泛适用的可描述衰减蠕变、稳态蠕变以及加速蠕变等三个阶段的拉伸蠕变损伤本构模型。研究成果对深部油气开采孔洞、深部地下洞室等围岩的变形与损伤扩展预测具有重要的理论意义与应用前景。

中文关键词： 直接拉伸；蠕变损伤；本构模型；深部岩体；数值仿真

英文摘要： Oil and gas well drilling and underground cavern excavating for the surrounding rock of deep high stress area is a long-term unloading process, while during this process the tensile stress is often appears. Due to the tensile strength of rock is only 1/6-1/32 of the compressive strength, therefore, using the traditional method of compression parameters has been unable to meet the needs of solving the deep surrounding rock rheological mechanics problems. In view of this, t In this project, the direct tensile creep test and the specimen fracture surface SEM test of the shale and sandstone that are in the deep oil and gas engineering and deep underground caverns marble will be take into account, while the deep hole creep damage simulation experiment and numerical simulation experiment were also carry out. On the basis of experimental research and combined with theory analysis, the tensile creep damage evolution mechanism of deep surrounding rock will be explored, the microscopic creep damage law of deep surrounding rock will be revealed, the function relationship between creep and damage will be discussed, finally, a tensile creep damage constitutive model of deep surrounding rock will be established that can widely used to describe in three stages of decay creep, steady creep and accelerated creep. Research on the

英文关键词： direct tension；creep damage；constitutive model；deep surrounding rock；numerical simulation