隧道Ⅳ级围岩上台阶爆破设计方案优化

Optimization of the bench blasting design scheme for gradeⅣsurrounding rock in tunnel

隧道Ⅳ级围岩光面爆破开挖通常采用YT-28型气腿式凿岩机进行打孔,工人在打周边孔时往往受到架设凿岩机条件的限制,导致周边眼实际倾斜角度远远大于设计倾斜角度,使爆破作业难于按照设计施工,现场技术员难于监管,分析原因与隧道爆破设计考虑现场的实际施工条件较少,设计比较理想化有很大关系。为了使设计和实际更加契合,使设计方案更易于实现,提出了相对应的爆破开挖优化方案。结果表明:优化后的爆破方案更有利于工人按照设计施工,有利于技术人员管理,同时爆破效果更好,为同类爆破作业提供了一定的参考价值。

The YT-28 air-leg rock drill is usually used in the smooth blasting excavation of gradeⅣsurrounding rock in the tunnel.When the workers are drilling the surrounding holes,they are often limited by the conditions of erecting the rock drill.It causes the actual inclination angle of the peripheral eye much larger than the designed inclination.From this perspective,it is difficult for blasting operations to construct according to the design,and it is difficult for on-site technicians to supervise.By analysis,the reason is found that the actual construction conditions at the site are less considered when designing the tunnel blasting scheme and the scheme is more idealized.In order to make the design more practical and the design easier to implement,optimization scheme is proposed.The results show that the optimized blasting plan is more conductive to conduct,and it is favorable for management.Moreover,the blasting effect is better,and it can provide a certain reference for similar blasting operations.