溢洪道安山玢岩基面保护层一次爆破开挖技术

Blasting Excavation Technology Without Protective Layer on Andesitic Porphyrite Foundation Surface

建基面是建筑物和地基的纽带,其稳定性和完整性直接影响建筑物的安全,如何在保证建基面完整性不遭破坏的前提下,完成建基面保护层一次爆破开挖施工是该技术研究的重点。在分析前坪水库安山玢岩“硬、脆、碎”岩性的基础上,开展了溢洪道安山玢岩基面保护层一次爆破开挖试验研究。结果表明:在岩石特性和炸药单耗量确定的情况下,通过控制爆破孔间排距和超钻深度,利用炸药锥形和环形聚能方法,采取柔性垫层措施,能够实现建基面保护层一次爆破开挖的目的,解决了常规模式下建基面开挖2~3次和耗时、耗工的难题,节省了人力、物力、财力,提高了施工效率,保证了施工质量。

The foundation surface is the link between the building and the foundation and its stability and integrity directly affect the safety of the building.How to ensure that the integrity of the foundation surface is not damaged,the completion of the foundation surface protection layer blasting excavation construction is the focus of the technical research.Based on the analysis of“hard,brittle and broken”lithology of andesitic porphyrite in Qianping Reservoir,a blasting excavation experiment was carried out on the base layer of andesitic porphyrite in spillway.By controlling the distance between blasting holes and the depth of overdrilling,using the method of coneshaped and ringshaped energy gathering and adopting flexible cushion,it can realize the purpose of 1 blasting excavation of the protective layer of the base surface,solve the problem of 23 times completion,timeconsuming and laborconsuming,save manpower,material and financial resources,improve the construction efficiency,guarantee the construction quality,and provide technical reference for the construction of the base surface blasting under the same rock conditions.