隧道周边不同位置径向裂纹对隧道围岩稳定性影响规律的研究  

Influence of radial cracks on stability of surrounding rocks at different locations around tunnel

作　　者：周磊[1] 朱哲明[1] 刘邦[1] 

机构地区：[1]四川大学建筑与环境学院能源工程安全与灾害力学教育部重点实验室,四川成都610065

出　　处：《岩土工程学报》2016年第7期1230-1237,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51074109);四川省科技计划项目(2014JY0002);油气藏地质及开发工程国家重点实验室资助项目(PLN1505)

摘　　要：在爆炸载荷作用下,隧道周边会产生大量的径向裂隙,研究在双轴压缩荷载作用下不同位置处径向单裂纹直墙拱形隧道的破坏规律,分两种情况进行研究,一种是裂纹在隧道拱肩或拱顶部位,以拱顶半圆圆心为基点的径向裂纹;另一种是裂纹在隧道底板或边墙部位,其裂纹面与隧道底板、边墙成135°夹角。采用模型试验和数值模拟方法进行研究,模型试验采用水泥砂浆制作隧道模型,数值模拟计算隧道模型裂纹尖端应力强度因子和应力云图,模拟结果与试验结果对比较吻合。结果表明:1裂隙会降低隧道整体的稳定性以及抗压强度;2当裂纹在隧道拱肩或拱顶部位时,裂纹倾角θ=45°时,隧道的稳定性最差,最容易破坏;3当裂纹在隧道底板与边墙交界处时,隧道最容易破坏,整体稳定性最差。In order toinvestigate the failure laws of straight wall tunnel with a single radial crackunder biaxial compression load, two casesare studied.Oneis the crack located in the arch shoulder to the vault with the vault semicircle center as the basis of radial crack.The otheris the crack located in the tunnel bottom or arch wall,and the angle betweenthe crack surface and the tunnel wallis fixed at 135 degrees. In the experiment,usingmodel tests and numerical simulations, the test samples of cement mortarare investigated. The stress intensity factor and the stress chart of the crack tipare numericallycalculated, and the simulated resultsare in good agreement with the experimentalones.The results show that： （1） The crack reduces the stability of the tunnel and the compressive strength. （2）Whenthe radial crack islocatedon the arch shoulderorthe vault with angleof 45 ＆#176;, the stability of the tunnelis the worst, andit is most easily damaged.（3）When the crackislocated at the junction between the arch bottom and the arch wall, the tunnelis the most vulnerable, and the overall stabilityis the worst.

关 键 词：隧道 应力强度因子 数值模拟 径向裂纹 

分 类 号：TU45[建筑科学—岩土工程]