摘要
利用二维真实破裂过程分析软件RFPA2D建立了在静载荷作用下含溶洞巷道围岩破坏过程的数值模型,分析了巷道拱顶、侧部及底部围岩中存在溶洞三种情况下巷道围岩的破裂过程,并与不含溶洞巷道的情况进行了对比。结果表明,巷道围岩中溶洞的存在,使得巷道围岩应力场和位移场的分布发生变化,在溶洞与巷道之间区域应力集中程度较大,破坏总是发生在巷道邻近溶洞一侧且与溶洞距离最近处。在相同加载条件下,三种情况中底部存在溶洞时围岩最先发生破裂,并迅速与溶洞贯通,使巷道底板破坏,底部溶洞对巷道的稳定性最为不利。在巷道周边存在的不同分布位置的溶洞,使得巷道围岩各部位的应力集中程度不同,靠近溶洞侧的围岩应力集中程度较大,围岩位移变化较大。
Using RFPA2D （ Two-dimensional Real Failure Process Analysis）, a numerical model of tunnel close to karst caves under static loads is established, and the failure process of surrounding rock mass is analyzed, inclu- ding the cases that the cave above, beside, or under the tunnel, comparing with the case surrounding rock mass with- out karst caves. The results of numerical calculation show changes for the distribution of the stress field and displace- ment field of surrounding rock mass with karst caves, and stress concentration is higher in the area between karst ca- ves and tunnel. Failure always occurs on the point the closest to the caves. Under the same condition of loading, while the cave exists under the tunnel, rock failures are faster than those at other situations, and develop quickly to the cave, which makes the bottom plate failed. So the karst cave existing under the tunnel is the worst of the three conditions for stability of surrounding rock mass. The stress concentration degree differs because of the different locations of karst caves around the tunnel, the stress concentration of the side closest to the caves shows larger concentra- tion, and larger change of displacement of surrounding rock mass.
出处
《地下空间与工程学报》
CSCD
北大核心
2014年第1期51-56,66,共7页
Chinese Journal of Underground Space and Engineering
基金
国家科技支撑计划(2012BAB08B06)
贵州省自然科学研究重点项目(黔教科2010003)
贵州省优秀科技教育人才省长资金项目(黔省专合字(2011)36号)
贵州省高层次人才科研条件特助经费项目(TZJF-2010年-044号)
关键词
深埋巷道
溶洞
数值试验
破坏过程
deep tunnel
karst caves
numerical test
failure process
