基于超声波实测的巷道围岩裂缝扩展和强度演变规律研究  

Crack propagation and strength evolution law of roadway surrounding rocks based on in-situ ultrasonic tests

作　　者：杨旭旭 吴岳[1] 靖洪文 YANG Xuxu;WU Yue;JING Hongwen(Shandong Key Laboratory of Disaster Prevention and Reduction in Civil Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)

机构地区：[1]山东科技大学山东省土木工程防灾减灾重点实验室,山东青岛266590 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116

出　　处：《采矿与安全工程学报》2021年第3期528-537,共10页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金青年科学基金项目(51704183);国家自然科学基金项目(51774192)。

摘　　要：基于对山东郓城煤矿巷道围岩体超声波波速的现场持续测试,研究巷道围岩体在开挖过程中裂缝扩展形式及其对围岩强度演变的影响。研究成果表明,巷道围岩体在开挖卸荷和应力分布不断调整的过程中,根据破裂区形成的时空效应,可将巷道围岩体由浅至深分为快速破裂区、渐进破裂区和稳定区。渐进破裂区的动态变化反映了巷道围岩体裂缝扩展的过程,即围岩体的破坏主要以裂缝扩展的单源破裂形式和双源破裂形式进行,且双源破裂是2个或多个破裂源共同作用的结果。围岩的双源破裂增大了围岩体强度衰减的程度,其强度演变曲线与传统研究成果存在一定差异,通过采用FLAC3D软件对强度衰减与不衰减模型进行对比,发现衰减模型后期应力环境更差,围岩承载力弱,对于认识巷道围岩强度分布规律和巷道围岩稳定性控制具有指导意义。Based on the results of consecutive ultrasonic tests on roadway surrounding rocks in Yuncheng Coalmine in Shandong Province, the study on crack propagation form and its influence on strength evolution of surrounding rocks during excavation was implemented. The research findings have shown that during excavation unloading and stress adjustment of rock mass, roadway surrounding rocks could be classified into three zones from shallow to deep: fast fractured zone, gradual fractured zone,and stable zone, according to the spatio-temporal effects formed in the cracks. The dynamic changes of gradual fractured zone reflect the process of crack propagation of surrounding rocks in roadways: the fracture of surrounding rocks is mainly in the forms of single-sourced fracture and double-sourced fracture of crack propagation, and the double-sourced fracture is the result of combined action of two or more fractured sources. The double-sourced fracture aggravate the attenuation of strength of surrounding rocks, whose strength evolution curves are different from those found in former studies.The comparison of the strength attenuation and non-attenuation models with FLAC3D software indicates that the stress environment is worse and the bearing capacity of surrounding rocks is weak in the late stage of the attenuation model. The study provides guidance on further understanding of strength distribution of surrounding rocks and stability control of roadways.

关 键 词：岩石力学 巷道围岩 超声波测试 裂缝扩展 强度演变 FLAC3D模拟 

分 类 号：TD353[矿业工程—矿井建设]