CN109029168B

CN109029168B - Blasting treatment method for underground suspended roof

Info

Publication number: CN109029168B
Application number: CN201810949704.1A
Authority: CN
Inventors: 高展; 李宏伟; 王学文; 王金刚; 江锡红; 范立超; 盖晓龙; 王伟
Original assignee: Hebei Iron and Steel Group Mining Co Ltd
Current assignee: Hebei Iron and Steel Group Mining Co Ltd
Priority date: 2018-08-20
Filing date: 2018-08-20
Publication date: 2020-11-03
Anticipated expiration: 2038-08-20
Also published as: CN109029168A

Abstract

The invention discloses a blasting processing method of an underground suspension roof, which comprises the steps of determining the position of the suspension roof at the maximum distance from the center of an access roadway after the suspension roof appears, wherein the position of a deep hole in a first row behind the suspension roof corresponding to the position is the position of an initiation point; and taking the initiation point as a midpoint, selecting 3-4 medium-length holes on two sides respectively, adopting a same-section double-initiation bomb charging mode, adopting a hole bottom initiation bomb charging mode for other residual medium-length holes in the same row, and performing collapse treatment on the suspended ceiling through differential blasting between holes in the same row. By adopting the method, the deep hole in the back row is normally blasted and stoped, and the method has the advantages that the deep hole in the front row cannot be damaged, the production cost of equipment is reduced, the hole repairing process of rock drilling equipment and the influence of a suspended roof on production arrangement are reduced, the normal stoping of a stope is ensured, and the safety of production and operating personnel is ensured.

Description

Blasting treatment method for underground suspended roof

Technical Field

The invention belongs to the technical field of mining, and particularly relates to a blasting treatment method for an underground suspended ceiling.

Background

In the mining process by adopting a sill pillar-free sublevel caving method, blasting stoping is carried out according to the sublevel height from top to bottom and according to the stipulation that the blasting of an upper sublevel is advanced and a lower sublevel corresponds to more than 5 rows of roadways, and a medium-length hole blasting ore-breaking mode is adopted for stoping; during the extraction operation, due to the reasons that the quality of the medium-length hole does not reach the standard, the charging operation is improper and the like, the suspended roof of the access road can be caused. The suspended ceiling is a position where the sublevel caving height does not reach the designed height, and top ore rock is not put down after blasting.

After the suspended roof appears, if the stoping is continued without processing, only a small part of ore can be mined, which causes resource waste and the possibility of collapse of the empty area at any time. At present, a known safe treatment mode for treating a suspended roof by medium-length hole blasting is to additionally incline a fan-shaped medium-length hole to a suspended roof area in a stoping roadway, and to perform tissue blasting by using a normal charging blasting technology with an empty field as a free surface. In actual operation, in order to ensure the safety of hole patching operators, the hole opening positions of the inclined fan-shaped medium-length holes can only be arranged 3-4 rows behind the brow line, and the suspended ceiling treatment mode mainly has the following three problems: firstly, hole patching can damage deep holes in the front 3-4 rows to cause perforation; and secondly, hole repairing generally needs more than 7 days at least to be finished (including site cleaning, rock drilling equipment calling, wind and water pipeline re-laying, site empty site measurement, medium-length hole design and construction and other works), and implementation of the mining plan at the level is seriously influenced. And thirdly, explosive which is not exploded is likely to remain in the residual hole in the suspended ceiling area, and the inclined fan-shaped medium-length hole has the possibility of penetrating the residual hole and has certain dangerous factors.

Disclosure of Invention

The invention aims to provide a blasting method of an underground suspended ceiling without hole patching.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: after the suspension roof appears, determining the position of the suspension roof at the maximum distance from the center of the access roadway, wherein the position of the deep hole in the first row after the suspension roof corresponding to the position is the position of the initiation point; and taking the initiation point as a midpoint, selecting 3-4 medium-length holes on two sides respectively, adopting a same-section double-initiation bomb charging mode, adopting a hole bottom initiation bomb charging mode for other residual medium-length holes in the same row, and performing collapse treatment on the suspended ceiling through differential blasting between holes in the same row.

The charging mode of the same-segment double-detonating projectile is as follows: filling a primer after the priming bomb and the detonating tube are filled in the bottom of the medium-length hole, and filling the primer to a position, 1-3 m higher than the suspended ceiling height, in the medium-length hole, and filling a second priming bomb and the detonating tube; the opening is then filled with explosive to a predetermined height and the opening is then filled with a bag.

The delay interval time of two adjacent sections of the detonating tube is 50ms, and 4-5 sections are selected for charging operation.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: according to the invention, hole patching is not needed, the production cost of equipment is reduced, the continuity of production arrangement is ensured, the operation is safe and simple, and no additional cost is needed to be added except a small amount of initiating explosive devices by blasting the deep holes in the back row. Adopting a same-row hole differential blasting mode, after 3-4 medium-length holes on two sides of a blasting point are drawn to be high and then the rear row caving height is reached, taking the blasting point position of the residual medium-length holes as a free surface, pushing the blasted ore rock to the blasting point and then falling into an empty field, increasing the rear row caving height by 1-3 meters compared with the front row suspension height, and entering a route after 2-3 times of repeated blasting to reach the normal ore mining condition; compared with the conventional method for compensating the inclined fan-shaped medium-length hole, the method for normally blasting and stoping the medium-length hole in the back row has the advantages that the medium-length hole in the front row cannot be damaged, the production cost of equipment is reduced, the hole compensating process of rock drilling equipment and the influence of a suspended ceiling on production arrangement are reduced, the normal stoping of a stope is ensured, and the safety of production and operating personnel is ensured.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a cross-sectional view of a horizontal downhole route in accordance with example 1 of the present invention;

fig. 2 is a 4 th explosion venting plan view in embodiment 1 of the present invention.

In the figure: the method comprises the following steps of 1, 2, 3, 4, 6, 11, 12 and 13, wherein the method is characterized in that the method is used for a route stoping roadway, 2 is a caving blasting pile, 3 is an empty area, 4 is a suspended roof, 5 is a 4 th row of route, 6 is a 5 th row of route, 7 is a 6 th row of route, 8 is a 7 th row of route, 9 is a horizontal cutting roadway, 10 is a covering layer, 11 is a hole opening reserved length, 12 is a blast hole (

holes

1, 2, 3.

Detailed Description

The blasting treatment method of the underground suspended ceiling comprises the following steps: after the suspended roof appears, measuring the height of the suspended roof in the sky plot, and determining the position of the maximum distance from the suspended roof to the center of the roadway for stoping of the approach, wherein the maximum distance is the maximum distance from the suspended roof to the center of the roadway for stoping of the approach after the previous row of caving; the backward extension line of the position along the roadway direction is intersected with the sector of the first row of medium-length holes behind the suspended roof, and the intersected position is determined as the position of the initiation point. And taking the initiation point as a midpoint, selecting 3-4 medium-length holes on two sides respectively, and adopting a same-section double-initiation bomb charging mode, wherein the other residual medium-length holes in the same row adopt a conventional normal hole bottom initiation bomb charging mode. The charging mode of the same-section double-detonating bullet is as follows: filling bottom powder into 3-4 medium-length holes on two sides of a detonating point after a primary detonating bullet and a primary detonating tube are filled in the bottom of the hole, filling the powder into the position, 1-3 meters higher than the suspended ceiling height, of the medium-length hole, filling a secondary detonating bullet and a secondary detonating tube, filling explosive to the conventional reserved height of an orifice, and filling a medicine bag in the orifice; the cantilever roof height is the distance from the forward extension line of the current medium-length hole along the roadway direction to the cantilever roof plate at the position corresponding to the eyebrow line sector to the center of the roadway; the detonating tube is preferably an OnryKai detonating tube and comprises 8 sections including 1 section, 3 sections, 5 sections, 7 sections, 9 sections, 11 sections, 13 sections and 15 sections, and 4-5 sections are selected from 8 sections for charging operation according to the requirement of field blasting; the delay interval time of adjacent 2 of the 8 segment bits is 50ms, for example, the delay interval time between 1 segment and 3 segments, and between 7 segments and 9 segments is 50 ms; the two detonating tubes in the middle deep hole adopting the double detonating bullet charging mode adopt the same section position. Performing online blasting by adopting a differential blasting mode among holes in the same row, and performing caving treatment on the suspended ceiling; the differential blasting is that 1 hole on each side of the position of the initiation point is a central hole and adopts a minimum section, the sections of the rest medium-length holes are symmetrically distributed by two central holes, two medium-length holes on one side are a section, the sections are sequentially increased in a gradient manner, and the section difference is generally selected to be 100 ms. The normal mining condition can be achieved after 2-3 times of repeated blasting, namely, the 1 st row and the 2 nd row (or the 1 st row, the 2 nd row and the 3 rd row) after the suspended roof are blasted by adopting the method, and the subsequent 3 rd row (4 th row) can achieve the normal mining condition.

Example (b): the blasting method of the underground suspended ceiling is concretely described as follows.

And adopting a sill pillar-free sublevel caving method for Hebei Chengde Heishan iron ore. The sectional height is 12 meters, the access distance is 15 meters, the Simba1254 electric hydraulic drilling jumbo is used as main drilling equipment, the hole arrangement of the medium-length hole adopts an upward fan-shaped arrangement mode, the diameter is 65mm, the row spacing is 1.5-2 m, the angle of the side hole is 45-60 degrees, and the hole bottom spacing is 2-3 m. The blasting charge uses a BQF-100 explosive loader, the explosive is modified ammonium nitrate fuel oil explosive, and 1-2 rows of deep holes are blasted each time according to the properties of ore rocks.

Fig. 1 is a cross-sectional view of a horizontal No. 12 underwell 600m drift, and as shown in fig. 1, the rear end of a horizontal No. 12 drift stoping roadway 1 of 600m is a caving blasting pile 2, and the upper space of the caving blasting pile 2 is an empty area 3; as shown in fig. 1, the overhanging roof 4 appears on the route row 3, which affects subsequent operations of the

subsequent route row

4, 5, 6, 7 and the like; the top of the No. 12 route is 616m horizontal cutting lane 9 and cover layer 10.

As shown in fig. 1, a suspended roof 4 is generated after the 3 rd row of horizontal 12 # approach of 600m underground is exploded, the height of the suspended roof is measured by using a measuring instrument, and an explosion point is arranged between the 4 th row of the 5 th maximum distance holes and the 6 th maximum distance holes corresponding to the maximum distance position of the suspended roof from the center of the roadway. Fig. 2 is a design diagram of a 4 th row blast of a horizontal No. 12 route of 600m, and as can be seen from the figure, the twelve blast holes 12 are, from left to right, a No. 1 hole, a No. 2 hole, a No. 3 hole. The method comprises the steps of adopting a same-section double-detonating bullet charging mode for No. 3, 4, 5, 6, 7 and 8 holes, adopting a hole bottom detonating bullet 13 for a first detonating bullet in a middle deep hole, determining the position of a second detonating bullet 13 according to the height of a suspended ceiling, adopting a hole bottom detonating bullet charging mode for the rest middle deep holes, carrying out explosive charging operation according to the section position required by design, using 1 section of Orykey detonator for No. 5 and 6 holes, using 5 sections of Orykey detonator for No. 3, 4, 7 and 8 holes, using 9 sections of Orykey detonator for No. 1, 2, 9 and 10 holes, using 13 sections of Orykey detonator for No. 11 and 12 holes, filling a medicine bag filler after the hole opening is charged to the hole opening length 11, connecting all Orykey detonator led out from the middle deep hole with a common detonating tube by using a common detonating tube, connecting wires, and finally detonating and processing the suspended ceiling.

And after the 4 th row of blasting, caving, blasting and ore discharging are carried out to the position of the brow line, the height of the suspended ceiling is measured again, the height of the suspended ceiling corresponding to the position of the brow line of the No. 4 to No. 7 deep holes in the 5 th row of blasting holes is averagely increased by 3.3 meters compared with the height of the suspended ceiling in the front caving, and the heights of other holes are increased by 1-2 meters and are different compared with the height of the front caving. And (4) adopting the same suspended ceiling treatment method for the row 5, wherein no empty area is seen in the blasting pile ore removal process, and the ore is already caved to the covering layer through calculation and comparison of ore removal amount and blasting amount. And the 6 th row adopts a hole bottom detonating bullet charging mode to blast, and places the initiation point at the No. 5 and No. 6 hole positions to ensure the blasting effect of the residual holes. Through 3 rows of blasting, the suspended roof problem is smoothly treated, and the subsequent production arrangement is ensured.

Claims

1. A blasting treatment method of a downhole suspended ceiling is characterized in that: after the suspension roof appears, determining the position of the suspension roof at the maximum distance from the center of the access roadway, wherein the position of the deep hole in the first row after the suspension roof corresponding to the position is the position of the initiation point; selecting 3-4 medium-length holes on two sides by taking a detonating point as a middle point, and performing collapse treatment on the suspended ceiling by performing differential blasting between holes in the same row in a manner of loading explosive by using a same-section double-detonating projectile in the same-row medium-length hole and loading explosive by using a hole bottom detonating projectile in the same-row other medium-length holes; and the maximum distance is the maximum distance from the suspended ceiling to the center of the roadway for stoping after the top row of the mining roadway falls over.

2. The method for blasting the suspended ceiling in the well according to claim 1, wherein the loading mode of the one-section double-priming-bomb is as follows: filling a primer after the priming bomb and the detonating tube are filled in the bottom of the medium-length hole, and filling the primer to a position, 1-3 m higher than the suspended ceiling height, in the medium-length hole, and filling a second priming bomb and the detonating tube; the opening is then filled with explosive to a predetermined height and the opening is then filled with a bag.

3. The blasting method of the underground suspended ceiling according to claim 2, wherein: and the delay interval time of two adjacent sections of the detonating tube is 50ms, and 4-5 sections are selected for charging operation.