摘要
Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of fractured rock mass.The strength and deformation features of grouting-reinforced rock mass were analyzed under different loading manners;the energy evolution mechanism of grouting-reinforced rock mass specimens with different particle sizes and features was investigated;the energy dissipation ratio and post-peak stress decreasing rate were employed to evaluate the bearing stability of grouting-reinforced rock mass.The results show that the strength and ductility of granite-reinforced rock mass(GRM)under biaxial loading are higher than that of sandstone-reinforced rock mass(SRM)under uniaxial loading.Besides,the energy evolution characteristics of grouting-reinforced rock mass under uniaxial and biaxial loading mainly could be divided into early,middle,and late stages.In the early stage,total,elastic,and dissipation energies were quite small with flatter curves;in the middle stage,elastic energy increased rapidly,whereas dissipation energy increased slowly;in the late stage,dissipation energy increased sharply.The energy dissipation ratio was used to represent the pre-peak plastic deformation.Under uniaxial loading,this ratio increased as the particle size increased and the pre-peak plastic deformation of grouting-reinforced rock mass became larger;under biaxial loading,it dropped as the particle size increased,and the pre-peak plastic deformation of grouting-reinforced rock mass became smaller.The post-peak stress decline rate A_(v) was used to assess the post-peak bearing performance of grouting-reinforced rock mass.Under uniaxial loading,parameter A_(v) exhibited reduction as the particle size kept increasing,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was greater,and the bearing capacity was greater;under biaxial loading,A_(v) increased with the p
为探究破碎岩体注浆加固对其承载特性的影响,对不同粒径、岩性的注浆结石体进行单双轴压缩试验,研究其力学特性及能量演化机制,并采用能量耗散比k及峰后应力跌落速率A_(v)评价注浆结石体承载的稳定性。结果表明,相比单轴加载,双轴加载下花岗岩结石体(GRM)的强度及延展性高于砂岩结石体(SRM);在单双轴加载下,注浆结石体的能量演化特征主要分为初期、中期及后期三个阶段,初期注浆结石体总能量W、弹性能WE及耗散能W_(D)较小,曲线较为平缓;中期W_(E)迅速增加,W_(D)缓慢增加;后期耗散能W_(D)急剧增加;注浆结石体容纳变形能力与k、A_(v)有关,单轴加载下,k随粒径增大而增大,峰前塑性变形范围增大,而A_(v)随粒径增大而减小,峰后容纳变形的能力增大,承载能力提高;双轴加载下,k随粒径增大而减小,峰前塑性变形范围缩小,A_(v)随粒径增大而增大,峰后容纳变形的能力降低,承载能力降低。本研究结果对不同岩性注浆提高巷道围岩稳定性具有一定的指导意义。
作者
WU Xu-kun
ZHAO Guang-ming
MENG Xiang-rui
LIU Chong-yan
LIU Zhi-xi
HUANG Shun-jie
ZHANG Qi-hang
吴旭坤;赵光明;孟祥瑞;刘崇岩;刘之喜;黄顺杰;张启航(Key Laboratory of Safe and Effective Coal Mining,Ministry of Education,Anhui University of Science and Technology,Huainan 232001,China;National Key Laboratory of Safe Mining of Deep Coal and Environmental Protection,Anhui University of Science and Technology,Huainan 232001,China;Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining,Anhui University of Science and Technology,Huainan 232001,China)
基金
Project(2023YFC2907600)supported by the National Key Research and Development Program of China
Project(202203a07020011)supported by the Major Science and Technology Projects of Anhui Province,China
Project(T2021137)supported by the National Talent Project,China
Project(T000508)supported by the Leading Talent Project of the Special Support Plan of Anhui Province,China
Project(GXXT-2021-075)supported by the University Synergy Innovation Program of Anhui Province,China
Project(2022AH010053)supported by the Excellent Scientific Research and Innovation Team of Universities in Anhui Province,China
Project(2022CX1004)supported by the Anhui University of Science and Technology Postgraduate Innovation Fund Project,China。
