Abstract: The selection of a reasonable blasting method is one of the key issues in the construction of large underground water-sealed caverns. Through field blasting test, blasting vibration monitoring, sound wave detection before and after blasting, as well as macroscopic investigation after blasting, we compared and analyzed the advantages and disadvantages of two blasting methods: deep hole bench blasting plus pre-splitting blasting, and horizontal shallow hole blasting plus smooth blasting. Results indicate that the blasting vibration and surrounding rock damage of the former method are greater than those of the latter, but still in controllable range and both methods meet the requirements of underground water-sealed cavern excavation molding. It’s concluded that the former method can be used for the excavation of large underground water-sealed caverns, but the drilling accuracy, single delay charge weight, charge diameter and charge structure should be strictly controlled. The latter method suits the excavation which requires strict control of blasting vibration or with poor rock mass .

Key words: underground cavern group, water-sealed, blasting method, pre-splitting blasting, smooth blasting