绿片岩软弱结构面的剪切蠕变特性研究

 针对锦屏II级水电站引水隧洞超埋深、高地应力的特点，选取边坡和地下洞室围岩中含有绿片岩软弱结构面的灰白色大理岩为研究对象，对含有软弱结构面的大理岩试样进行分级加载剪切流变试验，并对试验结果进行分析，探讨软弱结构面的蠕变特性。通过对不同法向应力条件下岩体结构面的蠕变力学特性及其规律的研究，以及对结构面剪切蠕变试验过程中的蠕变速率特性进行分析，结果显示结构面的剪切蠕变试验曲线表现出明显的3个阶段。在此基础上选用改进的Burger模型对结构面蠕变试验结果进行拟和分析，并讨论改进的Burger模型对于描述结构面剪切蠕变特性的适用性。

STUDY OF SHEAR CREEP CHARACTERISTICS OF GREENSCHIST DISCONTINUITIES

Based on the characteristics of high depth and high stress in diversion tunnel of Jinping II hydropower station，the gray marble containing greenschist discontinuities from the slope and underground rock cavern is selected as research object；and the shear creep test is carried out for the samples with greenschist discontinuities. The test results are analyzed and the rheological behaviors of greenschist discontinuities are discussed. The creep characteristics and mechanical laws of rock mass discontinuity under different normal stresses are studied；and the creep rate characteristics of discontinuities are investigated. Results show that the creep curves have obvious three stages. On this basis，the improved Burger model is selected for the analysis of creep test results；and a discussion on modified Burger model for describing the shear creep characteristics of discontinuities is presented.