端部消波和加密锚杆支护洞室抗爆能力模型试验研究

 利用抗爆模型试验装置，研究在集中装药爆炸应力波的作用下，端部消波和加密锚杆支护洞室的抗爆能力；分析和比较3个洞室的拱顶垂直压应力、顶底板相对位移、洞壁应变、顶底板加速度及洞室围岩宏观破坏分布形态的差别。试验结果表明：在爆炸应力波的作用下，当洞室没有发生严重破坏时，端部消波和加密锚杆支护洞室顶底板相对位移和拱脚处最大应变都有减小；拱顶加速度整体上都有不同程度的降低；3个洞室都在拱脚处两侧产生断裂缝，但端部消波和加密锚杆支护洞室在拱顶方向断裂缝明显减少，其拱顶破坏程度得到减轻。说明端部消波和加密锚杆支护洞室能够提高锚固洞室抗爆能力。

MODEL TEST RESEARCH ON ANTI-EXPLOSION CAPACITY OF UNDERGROUND OPENINGS WITH END WAVE-DECAY BY HOLES AND REINFORCED BY DENSE ROCK BOLTS

Based on anti-explosion model test device,the anti-explosion capacity of underground openings,which are reinforced by rock bolts with end wave-decay by holes and reinforced by dense rock bolts,is studied under explosive stress waves produced by focus charging. By comparing anti-explosion capacities of three underground openings,the differences of vertical stresses,relative roof-to-floor displacements of three underground openings,surface strains of three underground openings,accelerations of roof and floor of three underground openings and damage shapes of three underground openings are analyzed. The results show that under explosive stress waves,the relative roof-to-floor displacements and maximum surface strains of underground openings are reduced without severe damage;and the acceleration of roof is also decreased to certain degree. It is also shown that the fractures of underground openings are distributed at both sides of arch foots,but the fractures on the arches of two underground openings are fewer;and their surrounding rocks are lightly damaged. These conditions indicate that the underground openings with end wave-decay by holes and reinforced by dense rock bolts can increase their anti-explosion capacities.