Method for determining safety construction section of urban tunnel blasting explosive dosage based on controlled vibration velocity

Abstract

The invention discloses a method for determining tunnel construction positions corresponding to different designed explosive dosages when urban shallow-buried tunnel explosive design is conducted based on known controlled vibration velocity and protected buildings are located outside a tunnel contour line. According to the method, a reasonable method is used for establishing a coordinate system of a tunnel curve and a building contour line and an equation of locus according to the shape characteristics of a tunnel and a building; the extending lines of the building contour line divide the tunnel curve into a plurality of sections; and the piecewise function expression of a tunnel section safety distance corresponding to the designed dosage is deduced. After the minimum explosive dosage and footage corresponding to the shortest distance from the building to a blasting source are determined, the dividing line positions / pile numbers of all blasting dosages at the tunnel can be acquired precisely according to the obtained function expression, and the safety range of the tunnel designed footage can be determined. A precise method is provided for determining the safety blasting range of tunnel footage under a complex building environment.

Description

technical field [0001] The invention relates to a method for determining a safe construction area in blasting, and is particularly suitable for determining the safe area in blasting under the condition that a protected building exists outside the tunnel outline that requires low vibration velocity. Background technique [0002] In recent years, urban tunnel blasting has become a research hotspot, but there are few studies on the construction location corresponding to the safe charge under a certain vibration velocity. Due to the change of the distance between the explosion source and the protected object, the designed segmental charge / footage is constantly changing. In actual construction, the minimum charge is usually excavated for a certain distance at the point closest to the protected object. Keep it unchanged; increase the dose when the distance increases to the position where the normal dose can be used for construction. However, the common problem faced by urban shal...

AI Technical Summary

Problems solved by technology

However, the common problem faced by urban shallow-buried tunnels is that the buried depth of the tunnel is similar to the size of the building, and the building cannot be treated as a point. Therefore, it is very difficult to obtain the corresponding construction section under a certain vibration velocity and chemical dosage. After the minimum amount of chemical and footage required for the protected building, the boundary stake number between the minimum footage and the normal footage must be accurately determined, otherwise the vibration speed will easily exceed the standard

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