Deep hole step blasting method suitable for dam foundation in rich water environment and detachable device used for the method

Abstract

The invention discloses a deep hole step blasting method suitable for a water-rich environment dam foundation. The method is achieved through a detachable device. The detachable device comprises a PVC pipe, a flexible cushion layer, an energy dissipation base, a supporting rod and blasting charges, wherein the flexible cushion layer is laid at the bottom end of the PVC pipe, the bottom face of the energy dissipation base is arranged on the flexible cushion layer, the blasting charge is a cylinder with a through hole, internal threads matched with external threads of the supporting rod are formed in the inner surface of the through hole, the aperture of the through hole is matched with the outer diameter of the supporting rod, the supporting rod is detachably fixed to the top end of the PVC pipe, and one or more blasting charges are arranged on the supporting rod in series in a sleeving mode through the through hole. By means of the method, blasting can still be normally conducted under the water-rich environment, damage to rock at the bottom of a blasting hole can be effectively reduced, and the flatness of an excavation face is improved; in addition, all parts of the detachable device can be detached, and batched production and transportation are facilitated for plants.

Description

technical field [0001] The invention relates to the technical field of dam foundation blasting, in particular to a deep hole step blasting method suitable for dam foundations in rich water environments. Background technique [0002] At present, the commonly used methods for dam foundation excavation in water-rich environment include exposed blasting method, drilling blasting method and cavern blasting method. Among them, the drilling blasting method is the most commonly used, but it often causes serious water seepage in the hole. This situation on the water surface leads to difficulty in charging and poor blasting effect. At the same time, in most current drilling and blasting constructions, insufficient attention is paid to the protection of the bottom of the hole. In recent years, the sequential initiation method between holes with small steps with flexible cushions at the bottom of the hole is often used. However, due to the limited buffering effect of the flexible cushi...

AI Technical Summary

Problems solved by technology

However, due to the limited cushioning effect of the flexible cushion material on the blasting shock wave, the damage to the bottom of the hole is still relatively large, and the undulation of the excavated foundation surface is relatively large, resulting in a large amount of manual excavation

Although the traditional energy-gathering explosives and energy-dissipating seats with concave holes at the bottom of the hole for the purpose of improving the flatness of the excavation surface can increase the crushing effect in the horizontal direction, the energy-gathering effect of the device is limited, and the damage to the bottom of the hole is still great , not suitable for factory mass production

Images