Abstract:

In order to optimize the charge structure design of smooth blasting，LS-DYNA numerical

simulation software was used to simulate the rock clamping force around the smooth blasting hole，and the

effects of different confining pressures，different excavation sections and different blast hole lengths on the

rock clamping force around the blast hole were analyzed.The results show that the size of the tunnel excava⁃

tion section has little effect on the clamping force，while the confining pressure has a great influence on the

clamping force，which increases linearly with the confining pressure.Under different hole depths，the distri⁃

bution trend of clamping force along the hole depth is the same.The stress concentration in the orifice section

is small，and the clamping force in this section is the smallest.The clamping force shows a gentle growth

trend in the middle of the hole，and shows a steep upward trend near the bottom of the hole. This section is

the maximum clamping force section.The above research results provide a reference for the design of air

spaced charge structure and contribute to the refinement of design.

Key words:

tunnel blasting, clamping force, numerical simulation, fine blasting