A directional rock-breaking method with equivalent elliptical holes

Abstract

The invention relates to a directional rock breaking method by arranging an equivalent elliptical hole. The directional rock breaking method comprises the following steps that three circles with equalradius are selected, the straight line direction where the center of the circle is located is a designed breaking direction, the two centers of the circles are taken as two end points of the diameterof another circle, and an equivalent ellipse is obtained by drilling the circle; the equivalent elliptical hole is filled with static cracking agent slurry and is sealed; the static cracking agent slurry is subjected to hydration reaction and is condensed to form a cracking agent column body for applying radial expansion pressure to the hole wall, so that a rock mass surrounding the hole is subjected to the compressed stress action in the radial direction and is subject to the tensile stress action in the tangential direction, the obtained stress concentration coefficient of the position of the two vertexes of the long axis of the ellipse is maximum, and the stress concentration coefficient of the position of the two vertexes of the short axis is minimum; and expansion pressure provided is more and more large as the cracking agents continuously react, and directional rock breaking is realized. According to the directional rock breaking method by arranging the equivalent elliptical hole, the problem of directional rock breaking in the static cracking and rock breaking technology is solved, the purposes of fixed-point initiation of cracks and directional cracking are achieved, rockbreaking efficiency and the stone material yield are improved, and the purpose of controlling the cracking direction is realized.

Description

technical field [0001] The invention relates to a static expansion cracking agent rock breaking method, in particular to an equivalent elliptical drilling arrangement and a rock breaking method for static expansion cracking directional rock breaking and filling expansion cracking agent. Background technique [0002] The rock-breaking mechanism of the static expansion agent is that the hydration reaction of the expansion agent causes volume expansion and thermal expansion, which generates expansion pressure and acts on the hole wall, so that the broken rock mass around the hole is subjected to compressive stress in the radial direction and tensile stress in the tangential direction. . The tensile strength of brittle materials such as rocks is much smaller than its compressive strength. When the tangential tensile stress exceeds its tensile strength, cracks will initiate around the hole wall; as the expansion pressure continues to increase, the cracks will continue to expand u...

AI Technical Summary

Problems solved by technology

One of the disadvantages of this method is that if the rock mass is not completely broken, the guide device cannot be taken out from the borehole, and the guide device needs to be taken out through auxiliary drilling, which increases the drilling workload; Rigid guides are difficult

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