Methods, systems and equipment for determining the safe distance of air shock waves during tunnel blasting excavation

Abstract

This invention discloses a method, system, and equipment for determining the safe distance of air shock waves during tunnel blasting excavation, relating to the field of tunnel blasting excavation. The method includes: determining the overpressure safety control standard ΔP0 for air shock waves; calculating the overpressure ΔP1 of the air shock wave propagating along the tunnel and the overpressure ΔP2 of the air shock wave at the tunnel entrance based on blasting design parameters and tunnel characteristic parameters; calculating the overpressure ΔP3 of the air shock wave at any distance along the tunnel axis in an open-air environment at the tunnel entrance based on ΔP2; drawing a nomogram of the safe distance of the air shock wave action within the tunnel based on ΔP0 and ΔP1, and determining the first safe distance based on the nomogram; drawing an isopleth map of the air shock wave overpressure based on ΔP3, and determining the second safe distance based on ΔP0 and the isopleth map. This invention eliminates the need for extensive blasting tests, providing a new approach for the safety protection of blasting air shock waves near the tunnel face and entrance.

Images