循环荷载与水-岩次序作用下砂岩损伤力学特性研究

项目名称： 循环荷载与水-岩次序作用下砂岩损伤力学特性研究

项目编号： No.51309141

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 水利工程

项目作者： 邓华锋

作者单位： 三峡大学

项目金额： 25万元

中文摘要： 单独的循环荷载或水-岩作用均可造成岩石不可逆的渐进损伤，水电工程建设中形成的大量库岸边坡岩体可能要遭受二者的先后作用，因此，有必要对循环荷载与水-岩次序作用下岩石的力学特性进行研究。在理论分析的基础上，选取三峡库区库岸边坡消落带典型砂岩为试验研究对象，重点在试验方法和条件方面更加真实的模拟库水位反复升降变化和浸泡-风干的循环过程。一方面，对岩样先进行循环加卸载损伤，再进行水-岩作用试验；另一方面，对不同水-岩作用周期的岩样进行循环加卸载试验。综合岩样的物理、力学特性和微观结构的变化规律，较好的解释损伤岩样在水-岩作用下的劣化机理；分析得到水-岩作用下砂岩的动力响应特性变化规律；考虑岩样的初始损伤，将水-岩作用的劣化效应耦合到力学损伤中，建立典型砂岩的统计损伤本构模型。预期研究成果对大量存在的库岸边坡在考虑地震作用的长期稳定性评价，以及制定库区防灾减灾的中长远规划具有重要现实意义和应用价值。

中文关键词： 水-岩作用；循环加卸载；损伤；劣化机理；本构模型

英文摘要： Simple cyclic loading or water-rock interaction can cause irreversible progressive damage to rock, while large mumble of bank slopes which are formed in the construction of large hydropower projects, tend to suffer from the orainal action. Therefore, it is necessary for the study of rock mechanical properties, which under ordinal action of the cyclic loading and water-rock interaction. On the basis of theoretical analysis, sandstone in typical water-level-fluctuating zone of the three gorges reservoir area was selected as the experimental research object. The test simulates the repeated changes of reservoir water level and immersion-air dry circulation process more realistic in test method and test condition, on the one hand, use cyclic loading and unloading to make certain damage to rock sample first, then conduct the water-rock interaction test; on the other hand, conduct cyclic loading test on rock samples in different water-rock interaction period. The degradation mechanism under water-rock action of damaged rock samples can get a good explanation comprehensive with the change laws of physical, mechanical properties and microstructure; what's more, the dynamic response change rule of rock under the water-rock interaction can be analyzed; at the meanwhile, consider the initial damage of rock sample, the stati

英文关键词： water-rock interaction；cyclic loading；damage；deterioration mechanism；constitutive model