粉砂质泥岩不同加载控制方式下三轴压缩试验研究  

Research on Triaxial Compression Tests of Silty Mudstone in Different Loading Control Modes

作　　者：李蕊[1] 胡新丽[1] 丛璐[1] 徐腾飞 

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]深圳市市政设计研究院有限公司,广东深圳518000

出　　处：《铁道建筑》2016年第4期149-152,共4页Railway Engineering

基　　金：国家自然科学基金(41272305)

摘　　要：对秭归县马家沟滑坡中粉砂质泥岩开展三轴压缩试验,分析在应力和应变两种加载控制方式下岩石的变形破坏特征,以获取相对安全合适的试验加载方式。结果表明:在加载初期,各围压下两种加载控制方式的轴向应变和环向应变曲线具有较好的线性特征,峰值强度后变形特征差异显著;轴向应力加载控制方式下得到的岩石内摩擦角相对更大,摩擦力抵抗岩石变形破裂的能力相对较高,而环向位移加载控制方式下黏聚力抵抗岩石变形破裂的能力相对较高;试件破坏模式主要为低围压下的剪切-张拉破坏和较高围压下的剪切破坏,在轴向应力加载控制方式下试件的破坏程度相对剧烈,而环向位移加载控制方式下试件完整性相对较好,表明试件在环向变形量等速增加的制约下,岩石内部材料缓慢地达到承载极限,降低了灾变的可能性。The triaxial compression tests of silty mudstone from landslide were conducted in Majiagou,Zigui County. The deformation features under two loading control modes consisting of strain and stress were analyzed to obtain a relative safe and appropriate loading mode. The results show： At the beginning of the loading,both of axial and circumferential stain curve present good linear characteristics under two loading control modes,the differences of deformation characteristics are significant after peak strength. Under the axial stress loading control mode,internal friction angle is relative larger,and the friction is relative higher during the rock deformation and failure resistance. Under the circumferential displacement loading mode,cohesion is relative larger during the the rock deformation and failure resistance. The fracture modes are mainly shear-tension fracture with the low confining pressure and shear fracture with the high confining pressure; under the axial stress loading control mode,the damage degree of the specimens is oppositely severe,and the integrity of the specimens under the circumferential displacement loading control mode is better. It shows that internal material in the rock mass achieves loading capacity slowly to decrease the possibility of catastrophe with a constant increasing circumferential displacement.

关 键 词：粉砂质泥岩 三轴压缩试验 加载控制方式 变形破坏特征 强度参数 

分 类 号：TU411.5[建筑科学—岩土工程]