中文摘要：

采用先进的岩石全自动流变伺服仪,对坝基坚硬岩石变质火山角砾岩进行渗透水压力作用下的三轴流变力学试验。基于试验结果,研究变质火山角砾岩在不同围压下的蠕变特性,并分析岩石蠕变全过程中渗流速率随时间的变化规律。研究结果表明,当所施加应力水平小于岩石破裂应力水平时,变质火山角砾岩轴向蠕变变形不明显,且主要表现为稳态蠕变;当施加应力水平大于或小于但接近岩石破裂应力水平时,出现明显蠕变变形,蠕变速率开始增加,且发生加速蠕变破裂,表现出较为明显的加速蠕变特性。变质火山角砾岩环向蠕变变形量明显大于轴向蠕变变形量,表现出明显体积扩容现象。变质火山角砾岩稳态蠕变阶段的渗流速率随时间变化不大,但加速蠕变阶段的渗流速率明显增大,围压2MPa下变质火山角砾岩的渗流加速度大于围压6MPa下的渗流加速度。试验结果旨在为岩石流变本构模型及参数辨识提供可靠的试验依据。

英文摘要：

Rheological experiments of hard metamorphic-volcanic breccia specimens in dam foundation under triaxial compression with seepage pressure are carried out on the advanced rock servo-controlled triaxial rheology testing equipment. Based on experimental results of hard rocks,the creep properties of metamorphic-volcanic breccia specimens under different confining pressures are studied;and the variation of seepage rate with time in the stage of completed process of hard rock creep is analyzed. The results show that,when the applied stress level is considerably less than fracture stress,the creep deformations of metamorphic-volcanic breccia specimens are not obvious,and the main creep form is named steady state creep. On the other hand,when the applied stress level is greater than or less than but close to fracture stress,the creep deformations and accelerative creep characteristics become more obvious. Meanwhile,cracks of metamorphic-volcanic breccia specimens appear and spread. The metamorphic-volcanic breccia specimens show significant volume expansion phenomenon under triaxial compression;and circumferential creep deformations are obviously higher than those of axial creep deformations. The seepage rate of metamorphic-volcanic breccia in stage of steady state creep is not changed with time significantly. But in the stage of creep acceleration,the seepage rate increases evidently;and the seepage acceleration at confining pressure of 2 MPa is greater than those at confining pressure of 6 MPa. The results can provide dependable reference for the establishment of rock rheological model and parameter identification.