冻融条件下岩石损伤扩展特性研究(英文)

在冻融环境条件下,岩石内损伤裂纹的冻胀、开裂是一系列物理、力学复杂过程,所以研究冻融环境条件下岩石的损伤扩展机理具有重要意义。本文从损伤力学角度出发,借助于岩石损伤CT扫描实验研究冻融条件下岩石损伤扩展特性。主要做了以下两方面的工作一是研究冻融循环对岩石损伤的影响,从岩石的含水率、密度、损伤CT数的变化等实验现象,着重探讨冻融条件下岩石内部水分迁移、水冰相变对岩石损伤及其扩展的影响;二是研究了冻结温度对岩石损伤的影响,对实验现象主要从损伤CT数统计频率的变化来研究,分析时主要考虑了水冰相变体积膨胀和岩石材料本身物理特性两方面的因素。研究结果表明,冻融循环与冻结温度对岩石损伤有一定影响,而且就相同的温度条件来讲,岩石孔隙大小、孔隙贯通程度、孔隙率及岩石本身强度对损伤有着重要影响。

A Study on the damage propagation characteristics of rock under the frost and thaw condition

Under the frost and thaw condition, the damage propagation problem of rock is a complex physical and mechanical process. In this paper, two main tasks are presented by use of damage mechanics and CT technology. Firstly, the authors have studied the damage process of rock under different frost and thaw cycles, and discussed the influence of frost and thaw cycles on the damage propagation and the damage propagation constitutive relation of rock, water content and density. CT values are given to express the experimental phenomena of water migration and transition from water to ice. Secondly, the authors have studied frozen temperature imposing on rock damage and the experimental phenomena are reflected by statistical percentage. Two factors, the volume upheaval of transformation from water to ice and the volume shrink of rock materials when temperature decreases are considered. The experimental results show that the impact of frost and thaw cycles and frozen temperature plays an important role in the damage propagation problem of rock under frost and thaw condition.