摘要
采用静载模拟巷道初始地应力场,TNT爆炸模拟冲击地压,利用大型地质力学模型试验机对巷道在动、静荷载联合作用下的响应规律进行研究。试验中施加了相当于相似材料单轴抗压强度的最大静压力,荷载侧压比为1/3。在模型内部相同位置依次施加10,15和20 g TNT动荷载,在最后一次爆炸荷载作用下,洞室出现抛掷型冲击地压破坏现象。试验结果表明:巷道冲击地压灾害是动、静荷载联合作用的结果;在冲击瞬间作用下,冲击荷载与已存在静荷载叠加,使得巷道围岩压力迅速增加,叠加后作用力大于围岩承载能力时,引发围岩冲击破坏;围岩产生的冲击变形与巷道开挖后产生的初始变形叠加,形变超出围岩的变形能力时,洞壁首先发生破坏。围岩变形和冲击破坏范围与冲击力的大小及地应力水平相关性显著。
The large geomechanical model test to investigate the failure mechanism of rockburst tunnel under the static and explosive loads was carried out with the static load simulating the initial stress field and TNT explosion simulating the rockburst. The applied vertical pressure was equal to the uniaxial compressive strength of the similar material with the coefficient of lateral pressure of 1/3. Three levels of explosive loads were applied respectively. Rockburst phenomenon occurred when the last explosive load applied. The tunnel rockburst hazard was found to be the results of the combined action of dynamic and static loads. Impact load and the existing static load were superposed suddenly, which caused the superposed force to increase significantly and to be greater than the bearing capacity of the wall rock, leading to the rock impact failure to occur. The deformation due to impact and the initial deformation due to the tunnel excavation were superposed when the impact loads applied suddenly, leading to the failure of tunnel walls when the superposition deformation was greater than allowed. The deformation and the failure areas of the surrounding rock were affected by the impact load and the initial stresses.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2014年第10期2095-2100,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51109082)
河南省基础与前沿技术研究项目(142300413216)
河南省高等学校青年骨干教师资助计划(2013GGJS–083)
