粗糙度对硅质板岩–泥岩界面强度与变形特性影响试验研究  

Experimental study on effect of roughness on strength and deformation characteristics of interface between siliceous slate and mudstone

作　　者：祝艳波[1] 张宇轩 李文杰 杨凡凡 韩宇涛 李福通 兰恒星 ZHU Yanbo;ZHANG Yuxuan;LI Wenjie;YANG Fanfan;HAN Yutao;LI Futong;LAN Hengxing(College of Geological Engineering and Geomatics,Chang′an University,Xi′an,Shaanxi 710054,China;Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054 [2]中国科学院地理科学与资源研究所,北京100101

出　　处：《岩石力学与工程学报》2022年第7期1358-1372,共15页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金面上项目(41877247);国家自然科学基金重大项目(42041006)。

摘　　要：为探讨粗糙度对硅质板岩–泥岩界面强度与变形特性影响,利用界面剪切仪开展软–硬岩界面剪切力学特性试验研究,分析界面试样剪切破坏模式、变形特征、强度演化规律,并探讨粗糙度对软–硬岩界面强度影响机制。结果表明:(1)硅质板岩–泥岩界面剪切破坏模式分为界面间剪断、泥岩内剪断以及界面与泥岩混合剪断三类。界面粗糙度越大,试样剪切破坏模式越趋于泥岩内剪断;(2)粗糙度对硅质板岩–泥岩界面剪切变形影响显著,随界面粗糙度增大,其剪切刚度降低、峰值强度点位移增大,表明界面试样剪切破坏前更易变形、剪切破坏时产生的塑性变形量越大;(3)粗糙界面存在显著提升了硅质板岩–泥岩界面抗剪强度,且界面粗糙度越大,其峰值强度与残余强度提高幅度越高;粗糙度大幅提升了界面试样的黏聚强度,但对其摩擦强度提升幅度有限;(4)剪切过程中泥岩不断被硅质板岩粗糙界面铲刮挤密形成“硬化剪切带”,且界面糙度越大,“硬化剪切带”越厚,试样剪断面越趋于泥岩内部。而泥岩抗剪强度大于界面强度,因此界面强度随粗糙度增大而不断提高,且提高幅度受控于剪断泥岩的黏聚强度。To investigate the effect of the roughness on the strength and deformation characteristics of the interface between siliceous slate and mudstone,the direct shear test of interface specimens was conducted using an interface shear apparatus. The shear failure mode,the shear deformation and the strength characteristics of interfaces were analyzed,and then the influence mechanism of roughness on the shear strength increase of the interfaces was discussed. The results indicate that:(1) The shear failure modes of the interfaces of siliceous slate and mudstone are divided into cutting off along the interfaces,cutting off in mudstone and mixed shear-off between the interface and the mudstone.(2) Roughness has a significant effect on the shear deformation characteristic of the siliceous slate-mudstone interface. With increasing the roughness,the deformation modulus of the samples decreases and the shear displacement corresponding to peak strength increases,indicating that the deformation of interface samples during shearing are larger.(3) The roughness significantly improves the shear strength of siliceous slate-mudstone interface. The greater the interface roughness,the greater the increment of the peak strength and the residual strength of the interface are. The cohesion of the interface samples increases greatly with the roughness,whereas the friction angle hardly increases.(4) The mudstone is continuously scraped and compacted by the rough interface of siliceous slate during shearing,forming a “hardening shear band”. The greater the roughness of siliceous slate,the thicker the hardening shear band,and the shear plane of samples tends to occur in mudstone. As the shear strength of mudstone is greater than that of interfaces,the shear strength of interface samples increases continuously with increasing roughness,and its increment is mainly controlled by the cohesive strength of mudstone.

关 键 词：岩石力学 粗糙度 岩体界面 强度特性 变形特性 硬化剪切带 

分 类 号：TU45[建筑科学—岩土工程]