卸荷损伤节理岩体疲劳特性与水岩耦合流变特性研究

项目名称： 卸荷损伤节理岩体疲劳特性与水岩耦合流变特性研究

项目编号： No.51479102

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 水利工程

项目作者： 王瑞红

作者单位： 三峡大学

项目金额： 84万元

中文摘要： 节理岩体在加载与卸荷条件下，力学特性显著不同，卸荷将导致岩体质量急剧劣化，现阶段对于节理岩体卸荷条件下的损伤特性研究较少，且未考虑长期荷载和多种循环作用对卸荷损伤节理岩体力学特性的影响。本项目拟开展系统的物理力学试验，研究经历不同程度卸荷损伤后，节理岩体在多种因素影响下的力学特性：采用CT扫描、声波测试、电镜扫描等先进技术，对岩样卸荷后内部损伤程度进行定量地分析；开展不同程度卸荷损伤岩样的疲劳特性（主要考虑干湿循环、冻融循环、加卸荷循环三种因素）与水岩耦合流变力学特性试验，研究损伤岩体循环与长期载荷条件下的疲劳特征与时效特性，探讨卸荷量、循环次数、水压力、浸泡时间、溶液酸碱度等因素对岩体变形与强度参数的影响规律；揭示卸荷损伤岩体复杂因素影响下的损伤破裂演化机理，分别建立能描述岩体长期流变特征与循环疲劳特性的非线性损伤本构模型。研究成果可为开挖工程设计和建设提供技术参考。

中文关键词： 卸荷；损伤；节理岩体；试验研究；力学特性

英文摘要： The mechanical characteristics of jointed rock under the condition of unloading are significantly different from that of under the condition of loading，and the unloading would cause sharp degradation of rock mass quality. There is less research results about the damage characteristics of jointed rock under the unloading condition so far，and they are not involve the affection of long-term loading and multi cycle factors that acting on the mechanical characteristics of jointed rock. Many scientific physical and mechanical tests will be carried out in this project，and the mechanical characteristics of jointed rock will be studied which with different degrees damage under the influence of various factors. Using CT scanning，ultrasonic testing and SEM testing，the unloading damage degree is quantitative analyzed. The fatigue and aging characteristics of damage jointed rock under cycle and long-term loading conditions are studied. The influence rules of rock deformation and strength parameters are investigated under the action of unloading quantity，cycle times， water stress，soaking time，pH and other factors. The damage failure evolving mechanism of jointed rock in complex conditions is revealed， and the nonlinear damage constitutive model which can describe rheological and fatigue characteristics of rock are proposed. The research results can provide technical reference for the design and construction of excavation engineering.

英文关键词： unloading;damage;jointed rock;experimental study;mechanical characteristic