中山大学学报自然科学版 ›› 2019, Vol. 58 ›› Issue (6): 35-44.doi: 10.13471/j.cnki.acta.snus.2019.06.005

• 论文 • 上一篇    下一篇

红层裂纹软岩在水-应力耦合作用下的变形破坏试验

 周翠英1,3,苏定立2,3,邱晓莉4,杨旭1,3,刘镇1,3   

  1. 1.中山大学土木工程学院,广东 广州 510275;
    2.中山大学工学院,广东 广州 510275;
    3.中山大学岩土工程与信息技术研究中心,广东 广州 510275;
    4.广东天联电力设计有限公司, 广东 广州 510600
  • 收稿日期:2018-09-07 出版日期:2019-11-25 发布日期:2019-11-25
  • 通讯作者: 刘镇(1982年生),男;研究方向:软岩力学与工程;E-mail:liuzh8@mail.sysu.edu.cn

Experimental study of cracked soft rock with  hydro-mechanical coupling effect

ZHOU Cuiying1,3, SU Dingli2,3, QIU Xiaoli4, YANG Xu1,3,LIU Zhen1,3   

  1. 1.School of Civil Engineering, Sun Yat-sen University, Guangzhou 510275, China; 
    2.School of Engineering, Sun Yat-sen University, Guangzhou 510275, China; 
    3.Research Center for Geotechnical Engineering and Information Technology, Sun Yat-sen University, Guangzhou 510275, China;
    4.Guangdong Tianlian Electric Power Design Co. Ltd., Guangzhou 510600, China
  • Received:2018-09-07 Online:2019-11-25 Published:2019-11-25

摘要:

红层软岩遇水软化导致的工程灾变问题是许多重大工程的安全隐患之一。基于自主研发的TAW-100水-应力耦合软岩细观力学三轴试验系统,设计了软岩遇水崩解破坏试验、水-应力耦合作用下软岩蠕变特性试验和水-应力-裂纹相互作用下软岩变形破坏全过程试验等3类试验,系统的探索了不同赋存水环境条件下红层软岩遇水软化的力学行为, 阐明了水-应力-裂隙及其三者共同作用下软岩力学特性的变化规律。结果表明:软岩遇水崩解破坏的过程是经历新裂纹萌生、缓慢发育、加速扩展至贯通破坏等阶段;蠕变全过程中软岩所经历的各阶段特征较为一致;水-应力-裂隙三者之间的相互作用会加速软岩变形破坏的速度和进程,且影响软岩局部破坏的力学特性、各发展阶段持续的时间以及最终破坏模式。结合能量理论分析了水-应力-裂隙相互作用下软岩软化全过程中的渗流-化学-损伤能量转化及能量耗散。

关键词: 红层软岩, 水-应力耦合, 裂纹扩展, 蠕变, 变形破坏

Abstract:

Disaster induced by softening of saturated red-bed soft rocks is one of the major problems encountered frequently in the engineering construction in South China area. Three tests were conducted using the self-developed TAW-100 meso-mechanical triaxial test system of soft rock, including a disintegration test of soft rock in water, a creep test of soft rock under hydro-mechanical coupling condition and a triaxial test by observing the whole deformation and failure process of cracked soft rock under hydro-mechanical coupling condition. The mechanical failure behaviors of saturated soft rock in different engineering environments were investigated to analyze the influences of water, loading, cracks and their coupling effect on mechanical properties of soft rock. Results showed that the process of disintegration and failure of soft rock includes the stages of new crack initiation, slow development, accelerating expansion to penetration and failure. The characteristics of creeping stages of soft rock were consistent during the whole creep process. The coupling effect of water, stress and cracks will accelerate the deformation and damage of soft rock and influence the local mechanical characteristics, the duration of each stage and the final failure mode. The energy transformation and energy dissipation of seepage, chemical and damage in the whole process of soft rock softening under waterstressfracture interaction are analyzed based on the energy theory.

Key words: red-bed soft rock, coupled hydro-mechanical, crack propagation, creeping, deformation and failure

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