长龙山抽蓄电站光面爆破技术的应用

在长龙山抽蓄电站进场交通洞爆破工程中,通过使用新鲜毛竹片替代护臂套管的光面护壁爆破技术,精确布孔,增设导向套管,选择合理的爆破参数,并在掏槽中心设辅助空孔、孔角设贯缝孔等措施,提高了钻孔质量,有效减少了围岩的扰动和破坏,解决了起拱点位置炮孔利用率低的难题。最终取得了良好的光面爆破效果:Ⅱ类围岩半孔率94.8%,平均超挖量5.3cm,炮孔利用率94%;Ⅲ类围岩半孔率92.4%,平均超挖量8.6cm,炮孔利用率93%;Ⅳ类围岩半孔率80.2%,平均超挖量9.8cm,炮孔利用率90%。

Application of smooth blasting technology in Changlongshan pumping power station

In the Changlongshan pumping power station access tunnel blasting project,by using smooth wall blasting technology of fresh bamboo slice instead of casing of protective hole wall,arranging blasthole precisely,setting guide casing,selecting reasonable blasting parameters,setting auxiliary hole in the cutting center and seam in the hole angle,the quality of drilling was improved,the disturbance and destruction of the surrounding rock was effectively reduced and the problem of the low utilization rate of the blasthole was solved in the arch position.Finally a good smooth blasting effect was achieved.The class II surrounding rock: half hole rate was 94.8%,the average over-excavation was 4.7 cm and the utilization rate of the blasthole was 94%.The class Ⅲsurrounding rock: half hole rate was 94.2%,the average over-excavation was 8.6 cm and the utilization rate of the blasthole was 94%.The class Ⅳ surrounding rock: half hole rate was 80.2%,the average over-excavation was 9.8 cm and the utilization rate of the blasthole was 90%.