岩石节理流变力学特性及其本构模型

Shear Rheological Properties and Model for Rock Joints

通过对锦屏二级水电站大理岩节理进行剪切流变试验,分析了当剪切应力恒定、不同法向应力作用下的节理蠕变变形特性;根据传统的老化理论及遗传蠕变理论,提出了能够考虑法向应力影响的岩石节理剪切流变本构模型.最后,采用大理岩节理剪切流变试验数据确定了剪切流变模型的参数.将流变模型曲线和试验结果进行比较,结果表明该模型能够较好地描述不同法向应力和剪切应力作用下节理蠕变的变形规律.

Shear rheology tests were carried out to study the elastic-viscoplastic behaviour of marble rock joints from the Jinping Hydraulic Power Station. The variation law of shear displacement of rock joints with time is analyzed and the effect of normal stress on rheological properties of joints is studied. A rheological model with consideration of normal stress is built according to the aging theory and the genetic creep theory. Based on the result of tests on rock joints, the proposed model is identified and the parameters in the model are determined. Comparison between the model and test results shows that the proposed rheological model is reasonable.