强震区胶凝堆积体多尺度动力特性与灾变机理

For the cemented congeries of soil and rocks in hydropower engineering, the multi-scale digital characteristics of which are analyzed through 3D scanning technology，then site specimen or the bone rock mass is used as basic medium to prepare the specimen.Then based on the different degree of cementation and different micro, meso characteristics, the specimen are used to execute indoor 3D dynamic test, the falling weight test, site stress wave propagation testing of large scale. According to the experimental results and theoretical analyse between dynamic characteristic and stress wave propagation and meso-structure characteristic, multi-scale damage dynamic models with time dependent and cumulative effects are built up with the help of the homogenization. Then numerical simulation methods of different scale and span scale will be studied under the effect of earthquake loading. By means of case feedback study, the evolution and disaster mechanism of cemented congeries under reciprocating load are revealed. The research can contribute to the development of coupled system of multi-scale dynamics, damage mechanics, numerical simulation theory, it also helps to improve the understanding of physical and mechanical properties of cemented congeries of soil and rock medium in hydropower engineering and guarantee the safety of important engineering.

针对水电工程中常见的胶凝堆积体，在现场细观特征统计基础上利用激光三维扫描技术进行颗粒特征分析，采集原样或基于其数字化多尺度特征配制不同微、细观特征，不同胶结程度和孔隙率的试样。然后利用室内动态三轴试验、落锤冲击试验、场地大尺度应力波传播测试分析介质的动态力学特性与细观特征间的内在规律。然后采用均匀化方法概化材料，建立考虑率相关累积效应的多尺度损伤动力学本构模型，研究适用地震往复作用的多尺度、跨尺度胶凝堆积体数值模拟平台；借助实例开展反馈探讨，揭示地震作用下胶凝堆积体损伤演化的灾变机理；研究成果有助于拓展多尺度动力学、损伤力学、数值模拟理论等耦合体系向纵深发展，也有利于完善对水电胶凝堆积体物理力学性质的认识，保障重大工程安全。