Study on Failure Difference of Hard Rock Based on a Comparison Between the Conventional Triaxial Test and True Triaxial Test

Frontiers in Earth Science

卷:10

Guoqiang Zhu¹  Meiben Gao²  Yaohui Gao³  Kezhu Chen⁵  Guoqiang Zheng⁵  Junqian Ren⁶  Jicheng Sun⁷  Yonghui Tang⁷  Yan Zhang⁸ 

[1] Badong National Observation and Research Station of Geohazards, China University of Geosciences, Wuhan, China;

[2] Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Natural Resources, Fuzhou, China;

[3] PowerChina Huadong Engineering Corporation Limited, Hangzhou, China;

[4] School of Emergency Science, Xihua University, Chengdu, China;

[5] Sichuan Communication Surveying and Design Institute Co., Ltd, Chengdu, China;

[6] Sichuan Highway Planning, Survey, Design and Research Institute Ltd, Chengdu, China;

[7] Sichuan Transportation Construction Group Co., Ltd, Chengdu, China;

[8] State Key Laboratory of Geohazard Prevention and Environment Protection, Chengdu University of Technology, Chengdu, China;

关键词: failure;    deep hard rock;    conventional triaxial;    true triaxial;    mechanical properties;   

DOI  :  10.3389/feart.2022.923611

来源: DOAJ

【 摘 要 】

The study on the failure difference of deep hard rock based on the comparison between conventional and true triaxial tests can help us better understand the fracture processes and failure characteristics of the deep rock mass. Therefore, this article carries out a comparative analysis of the failure of hard rock under conventional and true triaxial stress states. Within the scope of this study, it is found that the brittle–ductile transformation properties can be intuitively reflected in the rock stress–strain curve and failure mode. The brittle–ductile transition point of rock can also be determined by the difference between peak and residual strengths. The rock failure strength increases with the increase of σ2, the peak strain decreases with the increase of σ2, the stress drop of the post-peak curve becomes more obvious with the increase of σ2, and the rock tends toward Class II brittle failure after the peak with the increase of σ2. When σ3 is relatively high, the rock fracture angle increases with the increase of σ2 with obvious regularity. Compared with conventional triaxial stress conditions, the differential stress-induced anisotropy failure is the biggest difference in rock fracture characteristics between true and conventional triaxial stress states. This study can supply useful references to the study of failure properties of hard rock under complex stress states.

【 授权许可】

Unknown