高地应力条件下隧洞围岩流变损伤机制数值模拟研究

发布时间：2018-03-01 17:39

本文关键词： 隧洞围岩流变损伤颗粒流数值模拟　出处：《现代隧道技术》2016年05期 　论文类型：期刊论文

【摘要】：高地应力条件下深部地下洞室的围岩均具有流变性,可能发生流变损伤甚至断裂,但该过程目前无法直接观测。为此,文章以锦屏二级水电站引水隧洞大理岩为研究对象,在三轴强度实验和流变损伤实验数据基础上,通过在颗粒流数值模拟方法中引入应力腐蚀模型,建立了能反映岩样短期和长期强度特征的数值模型。数值实验表明,不同应力状态下大理岩的微裂纹开裂类型、开裂方向、分布特征和扩展过程等呈现不同的规律,且随着围压的提高流变损伤效应将逐渐减弱。在岩石试样的损伤流变特征分析基础上,构建了锦屏二级电站引水隧洞的有限元数值模型,阐明了隧洞开挖过程中围岩的损伤演化机制。
[Abstract]:Under the condition of high ground stress, the surrounding rock of deep underground cavern has rheological behavior, which may occur rheological damage or even fracture, but the process can not be observed directly at present. Therefore, the marble of diversion tunnel of Jinping II Hydropower Station is taken as the research object in this paper. Based on the experimental data of triaxial strength and rheological damage, a numerical model which can reflect the short-term and long-term strength characteristics of rock samples is established by introducing the stress corrosion model into the numerical simulation method of particle flow. The microcrack cracking types, crack direction, distribution characteristics and propagation process of marble show different laws under different stress states. With the increase of confining pressure, the rheological damage effect will weaken gradually. Based on the analysis of the damage rheological characteristics of rock samples, the finite element numerical model of diversion tunnel of Jinping second stage Hydropower Station is established. The damage evolution mechanism of surrounding rock during tunnel excavation is expounded.
【作者单位】：中国地质大学(武汉)工程学院;武汉大学土木建筑工程学院;
【基金】：国家自然科学基金资助项目(41102196,51379194) 湖北省自然科学基金资助项目(2012FFB06502)
【分类号】：TV223

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