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蔡   林 ，王桂尧 ，郑   涛 ，刘剑航

 

（长沙理工大学 土木工程学院 ，长沙 410114)

摘   要 ：为系统揭示侧向刚度对岩体强度劣化及裂纹扩展机制的影响规律 ，引入初始损伤系数 γ开展含预制裂纹系统试样的双轴压缩试验。试验结果表明：侧向约束刚度对裂纹诱导的强度折损具有显著抑制作用 ，且抑制效应随侧向约束刚度和初始损伤系数  (0. 07 ~ 0. 64)  的增大呈非线性增长趋势 ；侧向约束刚度可以提升岩体起裂应力阈值 ，促进次生裂纹萌生 ，但翼型裂纹抑制效应受裂纹倾角调控 ；侧向约束刚度可约束岩体变形，驱动岩体破坏性质由脆性破坏向塑性破坏转变 ；侧向约束刚度促使试样破坏模式由弯折压溃破坏向直接压溃破坏转变。探明了侧向刚度对岩体力学行为及裂纹扩展行为的作用规律 ，提出了侧向约束刚度—裂纹倾角—初始损伤程度耦合模型 ，为隧道 、矿山等支护结构变刚度设计提供了理论支撑 ，推动支护结构向动态支护发展。

关键词：侧向刚度 ；损伤岩体 ；岩体强度 ；双轴压缩 ；裂纹扩展

中图分类号：TU45            文献标志码：A           文章编号： 1005- 8249   (2026)  01- 0156- 13

DOI:10. 19860/j.cnki.issn1005 - 8249.2026.01 .027

CAI Lin ,  WANG Guiyao ,  ZHENG Tao ,  LIU Jianhang

(School of Civil Engineering ,  Changsha University of Science and Technology ,  Changsha 410114 ,  China)

Abstract :  As significant support forms in engineering ,  flexible and rigid supports are widely employed ,  and their mechanical effects are closely associated with the  stiffness  characteristics  of the  support  structure .    To  systematically  disclose  the  influence  rules of lateral stiffness  on  the  strength  deterioration  and  crack propagation mechanism of  the  rock  mass ,   the  initial  damage coefficient  ( γ)  was introduced to represent the initial damage degree of the prefabricated crack system specimens .   Based on the self -  developed  test  device  with   adjustable  lateral  constraint  stiffness ,   biaxial   compression  tests  on  the  specimens  with prefabricated crack systems were conducted .   The test results  indicate that :  The total lateral stiffness has a remarkable inhibitory effect on the strength loss induced by cracks ,  and the inhibitory effect shows a nonlinear growth trend with the increase of lateral constraint stiffness  and  the  initial  damage  coefficient  (0. 07  - 0. 64) ;   The  lateral  constraint  stiffness  can enhance the  crack  initiation stress threshold of the rock mass and facilitate the initiation of secondary cracks ,  but the inhibitory effect on the wing -  shaped cracks is regulated by the  crack  inclination  angle;  The  lateral  constraint  stiffness  can  constrain  the  deformation  of the  rock mass and drive the failure nature of the rock mass to transform from brittle failure to plastic failure;  The lateral constraint stiffness prompts the failure mode of the specimens to change from bending and crushing failure to direct crushing failure .   The

research reveals the  evolution  law  of  the  rock  mass strength and  the transformation mechanism of  the  failure mode under the coupling effect  of  lateral   constraint  stiffness   and  initial  damage ,   and   establishes   the   mapping  relationship  among  support stiffness ,   initial damage coefficient ,   and failure  mode ,   providing a theoretical basis for the design of support structures and the assessment of surrounding rock stability.

Key words :  lateral stiffness;  damaged rock mass;  rock mass strength;  biaxial compression;  crack propagation

作者简介：蔡   林  (2000—) ,  男 ，硕士 ，研究方向：岩土工程。

通信作者： 王桂尧  (1963—) ,  男 ，博士 ，教授 ，研究方向：岩土工程与边坡工程。

收稿日期：2025 - 03 - 29