SU1523682A1 - Method of preventing rock bumps - Google Patents

Abstract

The invention relates to mining and can be used in the development of shock-hazardous formations. The purpose of the invention is to increase the effectiveness of the prevention of rock bursts and the safety of mining operations. An artillery gun is installed in the mine workings and a concrete-concrete sludge (BS) is shot at without a charge of explosives over an array of rocks (IHL). In the cavity formed, the character and position of the reference pressure zone, the distance from the bottom edge to the cross section, where the voltage does not exceed their values in an intact IHL, are determined, and a BS is shot with an explosive charge at this distance. As a result, a camouflet crushing zone is formed in the IHP and the pressure support zone moves into the depth of the IHF. Then, in BSB, the BS is delivered with the explosive charge to a depth determined depending on the distance from the production loop to the blasting site of the previous explosive charge, the coefficient taking into account the overlap of the cracks from the previous and subsequent charges, and the radius of the bursting cracks BS with charge of explosives. The shelling of BS BS is made before the displacement of the maximum of the reference pressure outside the protection zone and the decrease of the stresses in this zone to the level of the stresses of the intact IHL. 1 il.

Description

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| h

The invention relates to mining and can be used in the development of shock-hazardous formations.

The purpose of the invention is to increase the effectiveness of the prevention of rock bursts and the safety of mining operations.

The drawing shows a scheme for implementing the method.

The diagram shows: hearth, production 1, artillery gun 2, concrete-cutter d 3 without charge of explosive, an array of 4 mountain; rocks, a cavity formed by a concrete-drilling projectile 5j, a graph b of the distribution of the reference pressure P, the first projectile 7 with an explosive charge, zone 8 of camouflage crushers, the subsequent projecter 9 with an explosive charge, zone 10 cracking ( 4uflet crushing) from the explosion of a subsequent projectile, boundary 11 of the protective zone, curve 12, characterizing the reference pressure zone after carrying out the anti-shock measures, the level (ee of the stresses of the untouched massif, the protective zone.

The method is carried out as follows.

In the mine workout 1, an artillery gun 2 is mounted on the non-hazardous area and a concrete-piercing shot 3 is fired from it without charging an explosive substance to the rock massif 4. Moreover, this shot was made by an enhanced powder charge.

The character and position of the reference pressure zone P is determined by one of the known methods (for example, electrometric logging) using the resulting well 5. After that, according to the plotted graph of the reference pressure, the distance to the boundary of the section of the array with the level of stresses not exceeding the level of the intact array and the area of the reference pressure is determined: - the required location of the original camouflet crushing zone. Further according to the formula, 1

g To, sin And

-Speed rate at the time of meeting with the barrier, m / s; 35

- caliber guns, mm;

- barrier coefficient characterizing the properties of the medium:

q is the mass of the snare yes, kg; P - the angle of the meeting with the barrier; 1n is the depth of penetration of the projectile into the array.

The required initial flight speed is determined to penetrate into the massif at a depth of 1 and fires projectile 7 with an explosive charge. As a result, in rock massif 4 is formed at a distance of 1 from the mine working contour t an area of 8 cubic crushing with a radius The reference pressure zone is redistributed deep into the array by an amount equal to

A subsequent projectile 9 with a charge of blasting substance is delivered to the massif with the aid of an artillery gun 2 to a depth determined from

1 I + 2K R

tr

fde - the distance from the contour of generation to the place of previous charge, m; K is the coefficient taking into account the overlap of the zones of cracks from the explosion of the previous charge and the subsequent one;

KTP radius of the zone of crack formation of a projectile explosion with an explosive charge, m.

tr

0

five

0

five

After the explosion of the projectile 9 with a charge, a crevice zone 10 is formed with a radius of HYP which overlaps with the zone 8 of cracking from the explosion of the previous projectile 7, and the reference pressure zone moves further into the depth of the rock massif 4 to a depth of R2.

The shelling of an array of projectiles with a charge of explosive is produced by the described method until the maximum of the reference pressure wavelikely moves beyond the boundary 11 of the protective zone, and the value of the reference pressure within the protective zone does not exceed the level of stresses untouched array 6 After the shock prevention measures, the voltage reference voltage chart is characterized by curve 12 and corresponds to the III category of shock hazard.

formula and

five

3 o

 15

b e te n i

The method of preventing rock bursts, including the installation of an artillery gun in the mine, holding a shot at the face of a concrete-engaging projectile with explosive charge and installing an explosive charge explosive device in slow motion, characterized in that, in order to increase the effectiveness of prevention of rock bursts and safety mining operations, before a shot with a betbennoy projectile, a concrete projectile projectile is fired without explosive charge and the position of the reference pressure zone is determined along the resulting cavity. the nature and distribution of stresses, and the blasting of the first concrete-borne shell with an explosive charge is 1523682

are at a distance from the production contour, where the magnitude of the stresses does not exceed their values in the intact array, with each consecutive I concrete-cutting projectile with a charge of exploding 1B-active substance exploded, at a distance from the production contour, determined from the ratio

ten

 + t

1} + 2 CCtr,

five

where 1. K 0

The distance from the contour of the mine to the place of blast of the precursor charge; the S factor, which takes into account the overlap of the cracking zones from the adjacent explosive charges;

radius of cracking from a charge explosion.

Claims (1)

Claim A method of preventing mountain strikes, including installation in the production of an artillery gun, firing a shot at the face with a concrete-piercing projectile with an explosive charge with the installation of an explosive charge fuse for slow motion, characterized in that, in order to increase the effectiveness of prevention of mountain strikes and increase the safety of mining operations , before firing a concrete-slam shell, a shot is fired; d 'with a concrete-slam shell without charge (explosive material and along the cavity formed, determine the position of the reference pressure zone The structure and nature of the distribution of stresses, and the explosion of the first concrete-piercing projectile with an explosive charge is carried out at a distance from the output circuit, where the magnitude of the stresses does not exceed their values in an untouched massif, and each subsequent concrete-piercing projectile with an explosive charge is detonated. at a distance from the mine circuit, determined from the relation ⁼ 1 ϊ + 2KR _T p, where is the distance from the mine circuit to the place where the previous charge exploded; K is a coefficient that takes into account the overlapping of the zones of cracking from adjacent explosive charges; R _Tp is the radius of crack formation from a charge explosion.