Macro and micro failure mechanism of surrounding rock of small span tunnel under different stress paths

作     者：LIU He-yi CONG Yu ZHANG Li-ming ZHENG Ying-ren WANG Zai-quan ABI Erdi LIU Li-peng 刘和艺;丛宇;张黎明;郑颖人;王在泉;阿比尔的;刘立鹏

作者机构：College of Civil of EngineeringQingdao University of TechnologyQingdao 266033China Cooperative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic ZoneQingdao University of TechnologyQingdao 266033China Chongqing Jiaotong UniversityChongqing 400074China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin ChinaInstitute of Water Resources and Hydropower ResearchBeijing 100048China 

基　　金：Project(52179104)supported by the National Natural Science Foundation of China Projects(ZR2020ME099,ZR2020MD111,ZR2019BEE051)supported by the Shandong Provincial Natural Science Foundation,China 

出 版 物：《Journal of Central South University》 (中南大学学报（英文版）)

年 卷 期：2022年第29卷第5期

页      码：1616-1629页

摘      要：According to the different stress paths,similar model test and PFC simulation test of tunnel surrounding rock are designed to compare the failure mechanisms at macroscopic and mesoscopic *** following conclusions are drawn.1)Excavation unloading will disturb the surrounding rock to form a certain excavation damaged zone.2)Under the loading path,the stress of surrounding rock failure is 1.500 MPa;under the unloading path with initial stress of 60% σ_(Zmax) and 100% σ_(Zmax),the failure stress is 1.583 and 1.833 MPa respectively in the model test.3)In terms of the failure mode of rocks under different stress paths,tensile fractures first appear in two sides of the vertical walls;thereafter,the spandrel and arch foot are loosened due to the stress *** fractures gradually coalesce with those occurring in the vertical walls.4)In the process of excavation unloading,the proportion of shear cracks is 35.3%,and the rock is subject to strong shear *** final failure surface is approximately V-shaped.5)The tangential peak stress on the vertical walls at the free face is the lowest;the vertical walls at the free face show the poorest bearing capacity and are easily subjected to tensile failure.

主 题 词：stress paths similarity test PFC simulation excavation unloading macroscopic and mesoscopic scales 

学科分类：081406[081406] 08[工学] 0814[工学-地质类] 082301[082301] 0823[工学-农业工程类] 

核心收录：

D　O　I：10.1007/s11771-022-5041-6

馆 藏 号：203111965...