安全与环境工程2025，Vol.32Issue(5)：21-32,12.DOI:10.13578/j.cnki.issn.1671-1556.20250192
结构面拐点对花岗岩隧洞围岩失稳破坏机制影响的试验研究
Experimental study on the influence of structural plane inflection points on the instability failure of granite tunnels
摘要
Abstract
Affected by geological movements,the inclination of rock mass structural planes is prone to abrupt changes under in-situ stress,forming inflection points.To investigate the influence of structural plane inflection points on the instability and failure mechanism of tunnel surrounding rock,biaxial compression tests were conducted on granite tunnel specimens containing inflection points with the tip facing the tunnel,inflection points with the tip facing away from the tunnel,and specimens without structural plane inflection points.A comparison was made based on the digital image correlation(DIC)principal strain cloud maps,acoustic emission(AE)characteristic parameters,and stress-strain curves of the specimens.The results are as follows:① The relative position of the structural plane inflection point and the tunnel significantly affects the peak strength,axial strain rate,failure mode,and temporal distribution of AE count rates of the specimens.Compared to the specimens without structural plane inflection points,the specimens with the inflection point tip facing the tunnel exhibit ductile failure characteristics,with no significant change in peak strength but a notable increase in axial strain rate,and internal fracture signals generated earlier.In contrast,the specimens with the inflection point tip facing away from the tunnel exhibit brittle failure characteristics,with reduced peak strength and axial strain rate,and internal fracture signals concentrated between 90％of the peak strength and the failure stage.② The structural plane inflection point significantly influences the stress distribution of the specimens.The area where the inflection point tip faces the tunnel is a stress concentration zone,while the opposite side is a stress dispersion zone.When the tunnel is located in the stress dispersion zone,the damage degree of the sidewall closer to the structural plane is reduced,while that of the opposite side is significantly increased.When the tunnel is located in the stress concentration zone,the sidewall closer to the structural plane is prone to form interconnected failure with the inflection point,while the damage degree of the opposite side is lower than that of the specimens without structural plane inflection points.The findings of this study can provide a reference for analyzing the stability of tunnel engineering rock mass controlled by structural plane inflection points and predicting failure modes.关键词
结构面/双轴压缩试验/数字图像相关(DIC)/声发射(AE)/岩石力学/破坏机制Key words
structural plane/biaxial compression test/digital image correlation(DIC)/acoustic emission(AC)/rock mechanics/destruction mechanism分类
资源环境引用本文复制引用
陈燕和,明仁贵,陈东方,龙益彬,陈世杰,朱鑫杰,徐鼎平..结构面拐点对花岗岩隧洞围岩失稳破坏机制影响的试验研究[J].安全与环境工程,2025,32(5):21-32,12.基金项目
国家自然科学基金项目(52279117) （52279117）
