And it puts out the way to solve the present problem in unwatering by punching and blasting, and pumping water by intercepting ditch and dipping plash and infiltration well to solve the problems in pumping in the mining pit during rainy season in the strip mine.

In this paper,the technique of drilling and blasting dealing with the disconnected side under shallow water is studied.

In view of the shortage of Sodev s empirical formula which doesn t involve the free surface area,the calculating formula of vibration velocity in drilling blasting is put forward which can reflect the characteristics of the free surface area affecting the seismic intensity of blasting.

On the basis of practically measured data from seismic wave in a tunnel driving blasting, it is found, from analyzing the variation characteristics of vibration velocites of tunnel slope and surface under different explosive conditions, that the vibration velocity of a measured point is related to the free surface of drilling blasting besides the dose and blasting distance.