Deep foundation pit earth pressure controlled blasting method

Abstract

The invention discloses a deep foundation pit earth pressure controlled blasting method which comprises the following steps: before hole drilling, cleaning up floating slag, living stones and hydrops on a working face; perpendicularly drilling holes in a designated position, wherein the bottoms of shot holes are basically on the same horizontal plane; clearing the holes after hole drilling; producing stemming, selecting standard emulsion explosive for powder charging, using non-electric millisecond delay detonators and detonating cords, and carrying out firm wiring; covering blasting bodies with steel plates and sandy soil, and finally, releasing water to fill gaps in the shot holes and the up-down gaps of the steel plates; arranging sandy soil piles to surround the side, close to a high-tension cable, an existing line, a residential area and a workshop, of a bridge pier, especially the sections close to the high-tension cable and the existing line; arranging a blasting guard at each crossing; after a monitor sends out a blasting command, picketing and starting to carry out blasting after ensuring that the surrounding is safe by a blasting staff; and removing the guard after ensuring that a danger is removed. With adoption of the method, the construction speed is accelerated, the blasting shaking speed, blasting dust and noise are reduced, safety of the residential area and the workshop is ensured, the work hindrance problem by villagers is solved, and the economic loss of an enterprise is reduced.

Description

technical field [0001] The invention relates to a deep foundation pit earth pressure controlled blasting method for effectively eliminating flying stones, in particular to a controlled blasting technique for covering sand and soil above a blasting body. Background technique [0002] The total length of the extra-large bridge is 1959.65m, with 2 abutments and 58 piers. The pier foundations include bored piles, open-cut foundations, and well-dug foundations. The geological conditions of the deep foundations from top to bottom are: plain fill soil, silty clay, fine and coarse sand, and underlying fully weathered to weakly weathered granite. 53#~58# pier excavation well foundation depth is 6~8m, during site construction, dig down 2~3m on average and enter the weakly weathered granite. The super-large bridge is located in Laomanzi Village, Pulebao Town, Huanren County, close to existing lines, 220KV high-voltage lines, factories and residential areas. [0003] In order to ensur...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problems of flying rocks produced by conventional blasting excavation, and the non-blasting progress is too slow, etc., and propose a deep foundation pit blasting scheme that effectively eliminates flying rocks. The method is practical, efficient and economical

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