摘要
以砂岩为研究对象,通过分级循环加卸载试验研究脆性岩石在分级循环加卸载作用下的损伤特性和演化规律。基于试验结果,定义了损伤值,推导出适用于加载阶段和卸载阶段的损伤本构模型。研究结果表明:提出的循环加卸载下的岩石损伤本构方程与试验应力应变曲线拟合度比较高,证明了其合理性和适用性。该损伤本构模型和定义的损伤值可以正确地反映出岩石的损伤演化过程,能够描述岩石破坏的各个阶段。参数敏感性对本构模型有不同程度的影响。
Taking sandstone as the research object, the damage characteristics and evolution laws of brittle rocks under graded cyclic loading and unloading are studied through graded cyclic loading and unloading tests. Based on the test results, the damage values are defined and the damage constitutive models for loading and unloading stages are derived. The results show that the proposed constitutive equation of rock damage under cyclic loading and unloading has a high fitting degree with the experimental stress-strain curve, which proves its rationality and applicability. The damage constitutive model and the defined damage value can correctly reflect the damage evolution process of rock and describe each stage of rock failure. The sensitivity of parameters has different effects on the constitutive model.
引文
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