LAUSR

Abstract The traditional excavation method of dam foundation protective layer has low production efficiency due to complicated working procedure and small working face area. As a result, the progress of the project will be delayed and the engineering benefits will be reduced. This paper puts forward a new blasting technique with a shock-reflection device arranged at the bottom of vertical borehole for rapid excavation of dam foundation. Combination of theoretical and damage analysis at the bottom of borehole, the new blasting technique is verified, and the field experiment results show that the blasting technique can be used for dam foundation excavation. This blasting technique can reduce the dynamic damage in foundation rockmass, which reduces the potential harm of the blasting to the dam foundation. And the construction process is simple, which can be used for excavation of dam foundation in a large scale. If this blasting technique can be widely applied, it will speed up the construction speed of hydropower stations and bring huge economic benefits.