叶巴滩水电站左岸坝肩槽开挖爆破技术

Excavation Blasting Technology for Left Bank Abutment Slot of Yebatan Hydropower Station

拱坝坝肩槽的开挖质量对工程运行的安全有重要影响,基于叶巴滩水电站左岸坝肩槽开挖,采用预裂孔+垂直梯段孔爆破技术搭配合理的钻爆参数,严格控制装药量及最大单响药量,并采用分段微差延时爆破技术,取得了良好的开挖效果并积累丰富的工程经验。现场开挖施工结果表明,坝肩槽开挖成型优良,且有效减少对保留岩体的损伤,使坝肩槽爆破开挖质量满足设计要求。

The operation safety of arch dams is greatly affected by the excavation quality of the abutment slots.The excavation blasting technology adopted in the left bank abutment slot of Yebatan Hydropower Station is introduced.Pre-splitting holes and vertical bench blasting technology are adopted with reasonable drilling and blasting parameters.The blasting charge amount and the maximum single-shot charge amount are strictly controlled.And the segmented millisecond delay blasting technology is adopted.With these technologies,satisfactory excavation performance is achieved and useful experience is accumulated.The on-site excavation results show that the abutment slot is well formed and the damage of the retained rock mass is effectively reduced,ensuring that the blasting excavation quality of the abutment slot meets the design requirements.