阅读说明：本技术 一种上盘破碎矿体长锚索整体预支护方法 (Integral pre-supporting method for upper-plate crushed ore body long anchor cable ) 是由 范纯超 刘再涛 侯成录 王辉 王栋毅 刘博� 赵印宣 徐静静 李佳伦 于 2021-06-22 设计创作，主要内容包括：本发明公开了一种上盘破碎矿体长锚索整体预支护方法,沿各分段矿体下部的凿岩横巷掘进上盘围岩破碎带平行开凿两条脉外巷道,并沿矿体走向开凿锚索固定巷；然后在锚索固定巷中布置钢梁；之后在各分段矿体下部的凿岩横巷中,沿倾斜矿体边缘在矿体里面向上钻凿锚索钻孔,穿过锚索钻孔布置长锚索,并将长锚索固定在锚索固定巷的钢梁上；最后向其锚索钻孔内注浆。通过地锚实现长锚索与上盘岩体共同受力,更加有效地对倾斜且围岩破碎的厚大矿体上盘进行加固,进一步提高上盘三角矿体的回采安全系数。(The invention discloses a method for integrally pre-supporting a long anchor cable of an upper-wall crushed ore body, which comprises the steps of excavating an upper-wall surrounding rock crushing zone in parallel along a rock drilling cross roadway at the lower part of each segmental ore body, and excavating an anchor cable fixing roadway along the direction of the ore body; then arranging steel beams in the anchor cable fixing lane; then, in a rock drilling cross lane at the lower part of each segmental ore body, drilling anchor cable drill holes upwards in the ore body along the edge of the inclined ore body, penetrating the anchor cable drill holes to arrange long anchor cables, and fixing the long anchor cables on steel beams of anchor cable fixing lanes; and finally, grouting into the anchor cable drilling hole. The long anchor cable and the hanging wall rock mass are stressed together through the ground anchor, the hanging wall of the inclined thick and large ore body with broken surrounding rock is reinforced more effectively, and the recovery safety coefficient of the hanging wall triangular ore body is further improved.)

1. An integral pre-supporting method for a long anchor cable of an upper-plate crushed ore body is characterized by comprising the following steps:

s1, excavating an upper wall rock crushing zone along a rock drilling cross roadway at the lower part of each segmental ore body, excavating two vein outer roadways in parallel, and excavating an anchor cable fixing roadway along the direction of the ore body;

s2, arranging steel beams in the anchor cable fixing lane, wherein two ends of each steel beam extend into the upper wall rocks, drilling a plurality of groups of anchor cable drilling holes in the upper wall rocks on two sides of each steel beam, then using two fixed anchor cables to penetrate into the anchor cable drilling holes and grouting the fixed steel beams, namely fixing the steel beams by using ground anchors;

s3, drilling anchor cable drill holes upwards in the ore body along the edges of the inclined ore body in the rock drilling cross drift at the lower part of each sectional ore body;

s4, penetrating the anchor cable drill holes to arrange long anchor cables, and fixing the long anchor cables on steel beams of the anchor cable fixing lane; and S5, after the installation of each long anchor cable is finished, grouting into the anchor cable drilling hole.

2. The method for integral pre-support of the upper-disk crushed ore body long anchor cable according to claim 1, wherein in step S1, the height of the extravenal roadway is gradually reduced to the same height as the anchor cable fixing roadway for placing the steel beam in the extravenal direction.

3. The method for integral pre-support of the upper disk crushed ore body long anchor rope as claimed in claim 1, wherein in step S1, the length of the extravenal tunnel is 6.0 m.

4. The method for integrally pre-supporting the upper-wall crushed ore body long anchor cable according to claim 1, wherein in step S2, the steel beam is driven into the upper-wall surrounding rock 0.5m deep in the anchor cable fixing roadway, and is fixed by a plurality of groups of two long anchor cables driven into anchor cable drill holes, and C30 concrete is used for grouting into the anchor cable drill holes.

5. The method for integral pre-support of upper disk crushed ore body long anchor cable as claimed in claim 1, wherein in step S3, the pitch between adjacent anchor cable drill holes is the same in the anchor cable drill holes drilled in the ore body along the inclined ore body edge.

6. The method for integral pre-support of upper-disk crushed ore body long anchor cable according to claim 1, wherein in step S3, the distance between the anchor cable drill hole drilled in the ore body along the inclined ore body edge and the ore body edge is 1.0 m.

7. The method for integral pre-support of upper disk crushed ore body long anchor cable as claimed in claim 1, wherein in the step S3, in the anchor cable drill holes drilled along the edge of the inclined ore body, the distance between the anchor cable drill holes at two ends and the edge of the rock drilling roadway is smaller than the distance between the adjacent anchor cable drill holes.

8. The method for integrally pre-supporting the upper-disk crushed ore long anchor cables as claimed in claim 1, wherein in step S4, the long anchor cables are fixed to the steel beam end to end, and every three long anchor cables are connected together by the anchor cable holder.

9. The method for integral pre-support of an upper-disk crushed ore body long anchor cable as claimed in claim 1, wherein in step S5, C30 concrete is used for grouting into the anchor cable bore hole.

Technical Field

The invention relates to a method for reinforcing surrounding rocks of mine ore bodies, in particular to a method for integrally pre-supporting a long anchor cable of an upper-wall broken rock body.

Background

In the process of extracting the inclined thick ore body by adopting the medium-length hole sublevel mining method, if the upper wall surrounding rock of the inclined ore body is unstable, the safety of a stope is poor, so that the upper wall triangular ore body is difficult to extract, and the safe, efficient, low-cost and large-scale extraction of the inclined thick ore body is limited. Aiming at the problem, in the engineering practice, the hanging wall surrounding rock is usually reinforced by methods such as an inclined ore body vertical stabilization method, hanging wall surrounding rock concrete column reinforcement and the like, but the two schemes can cause the loss of part of ore bodies of the hanging wall triangular ore body and the dilution of the hanging wall triangular area surrounding rock in the caving process, and meanwhile, the support reliability is poor.

Anchor cables are a support means which is developed recently and widely used, and are commonly used in places with large engineering scale, important importance, complex geological conditions and difficult support. The anchor cable has obvious supporting effect and simple use condition, some mines are listed as a common means for processing complicated address conditions, and particularly rock mass subareas mined in deep parts have to be supported by the aid of the anchor cable.

Therefore, by means of the anchor cable technology, a feasible method for integrally pre-supporting the upper plate broken rock mass is searched, and the upper plate broken rock mass are stressed together through the ground anchor, so that the stability of the upper plate broken surrounding rock is improved, and the safe mining of the upper plate triangular ore body is realized.

The Chinese patent application with publication number CN112664194A discloses an 'integral reinforcing method for a hanging wall broken surrounding rock long anchor cable', and the construction range of the reinforcing method is outside the pulse, so that the ore loss is reduced. However, the method provides a space for mounting and constructing the steel beam anchor cable by extending the ore discharge chambers at the lower parts of the segments towards the upper wall of the ore body to form extravenal chambers. On the other hand, the steel beam anchor cables are arranged in parallel, so that a larger extravenal chamber space is required, the excavation amount is increased, the using amount of the steel beams and the anchor cables is increased, and the extravenal chamber needs additional supporting engineering, so that the construction cost is further higher.

Disclosure of Invention

The invention aims to solve the technical problem of providing an integral pre-supporting method for a long anchor cable of an upper-wall crushed ore body, realizing the common stress of the long anchor cable and the upper-wall rock body through an earth anchor, more effectively reinforcing the upper wall of a thick ore body which is inclined and has broken surrounding rocks, and further improving the recovery safety coefficient of the upper-wall triangular ore body.

The technical scheme of the invention is as follows:

an integral pre-supporting method for a long anchor cable of an upper-plate crushed ore body is characterized by comprising the following steps:

s1, excavating an upper wall rock crushing zone along a rock drilling cross roadway at the lower part of each segmental ore body, excavating two vein outer roadways in parallel, and excavating an anchor cable fixing roadway along the direction of the ore body;

s2, arranging steel beams in the anchor cable fixing lane, wherein two ends of each steel beam extend into the upper wall rocks, drilling a plurality of groups of anchor cable drilling holes in the upper wall rocks on two sides of each steel beam, then using two fixed anchor cables to penetrate into the anchor cable drilling holes and grouting the fixed steel beams, namely fixing the steel beams by using ground anchors;

s3, drilling anchor cable drill holes upwards in the ore body along the edges of the inclined ore body in the rock drilling cross drift at the lower part of each sectional ore body;

s4, penetrating the anchor cable drill holes to arrange long anchor cables, and fixing the long anchor cables on steel beams of the anchor cable fixing lane; and S5, after the installation of each long anchor cable is finished, grouting into the anchor cable drilling hole.

Preferably, in step S1, the height of the extravenal roadway is gradually reduced to the same height as the anchor cable fixing roadway on which the steel beam is placed in the extravenal direction.

Preferably, in step S1, the length of the extrapulse lane is 6.0 m.

Preferably, in step S2, the steel beam penetrates into the upper wall rock 0.5m deep in the anchor cable fixing roadway, is fixed by a plurality of groups of two long anchor cables penetrating into anchor cable drill holes, and is grouted into the anchor cable drill holes by using C30 concrete.

Preferably, in step S3, of the anchor line drill holes drilled in the ore body along the inclined ore body edge, the pitch between adjacent anchor line drill holes is the same.

Preferably, in step S3, the anchor line bore drilled in the ore body along the inclined ore body edge is at a distance of 1.0m from the ore body edge.

Preferably, in the anchor line drill holes drilled along the edge of the inclined ore body, the distance between the anchor line drill holes at two ends and the edge of the rock drilling roadway is smaller than the hole distance between the adjacent anchor line drill holes in step S3.

Preferably, in step S4, the long anchor lines fixed to the steel beam end to end are connected together by anchor line holders in groups of three long anchor lines.

Preferably, in step S5, C30 concrete is used to grout into the anchor cable bore.

The invention has the following beneficial effects:

according to the basic technical scheme, an upper-wall surrounding rock excavating vein outer roadway and an anchor rope fixing roadway are excavated along a lower rock drilling cross roadway of a segmented ore body, steel beams are arranged in the anchor rope fixing roadway, anchor rope drill holes which are parallel to each other and distributed at intervals are drilled in the ore body along the edge of an inclined ore body, long anchor ropes are arranged through the anchor rope drill holes, the long anchor ropes are fixed on the steel beams in an end-to-end mode, the upper-wall broken surrounding rock is reinforced through the long anchor ropes, the stability of a stope is improved, and the safety of upper-wall triangular ore body mining is effectively guaranteed. The method avoids the ore loss and ore dilution caused by reinforcing the upper wall broken surrounding rock by adopting methods such as an inclined ore body vertical stabilization method, upper wall surrounding rock concrete column reinforcement and the like, and greatly improves the economic benefit.

And the height of the extravenal tunnel is gradually reduced to the same height with the anchor cable fixing tunnel towards the extravenal direction, so that the excavation amount is reduced, the labor intensity is reduced, and the mining cost is saved. The long anchor cable is fixedly connected with the steel beam head and the tail, so that when the long anchor cable is subjected to the tensile stress of the surrounding rock on the upper disc, the steel beam provides a better stress point for the long anchor cable, and the long anchor cable is larger in stress limit and more uniform in stress.

Compared with the 'method for integrally reinforcing the long anchor cable of the upper-disc broken surrounding rock' (publication number CN 112664194A), the method has the following characteristics: the drilling positions of the first long anchor cable and the long anchor cable are in the ore body, so that disturbance to the upper wall surrounding rock is avoided. And secondly, arranging anchor cable fixing lanes of the steel beams in the surrounding rock, thereby reducing the excavation workload and reducing the using amount of the steel beams. Thirdly, the invention provides a new stress model for fixing the long anchor cable, and the long anchor cable pre-support is more suitable for ore bodies with larger inclination angles.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic diagram illustrating the principle of an upper-disk crushing ore body long anchor cable pre-supporting method according to an embodiment of the present invention;

FIG. 2 is a sectional view taken along line II-II of FIG. 1;

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 1;

fig. 5 is a schematic view of a connection mode of a long anchor cable and a steel beam according to an embodiment of the present invention.

In the figure, 1: rock drilling cross drift, 2: hanging wall rock, 3: extravenous laneway, 4: anchor cable fixing lane, 5: steel beam, 6: anchor rope drilling, 7: long anchor cable, 8: iron wire, 9: an anchor cable fixer.

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, and it is to be understood that the detailed description is provided for purposes of illustration and explanation and is not intended to limit the scope of the invention.

As shown in fig. 1 to 5, the method for pre-supporting the upper-disk crushed ore long anchor cable according to the basic embodiment of the present invention comprises the following steps:

and S1, excavating two parallel extragangue roadways 3 with moderate intervals in the upper plate surrounding rock 2 crushing zone along the rock drilling cross drift 1 at the lower part of each segmental ore body, and pulling apart along the direction of the ore body to form an anchor cable fixing roadway 4.

S2, arranging steel beams 5 in the anchor cable fixing lane 4, enabling two ends of each steel beam 5 to extend into the upper disc surrounding rocks 2, drilling a plurality of groups of anchor cable drilling holes 6 in the upper disc surrounding rocks on two sides of each steel beam, then fixing the steel beams 5 by using a plurality of groups of double fixed anchor cables to penetrate into the anchor cable drilling holes 6, and grouting the anchor cable drilling holes 6.

S3, in the rock drilling cross drift 1 at the lower part of each segmental ore body, anchor line boreholes 6 are drilled upwards inside the ore body along the edges of the inclined ore body.

And S4, arranging the long anchor cable 7 through the anchor cable drilling hole 6, and fixing the long anchor cable 7 on the steel beam 5 of the anchor cable fixing lane 4 by using the iron wire 8 and the anchor cable fixer 9.

And S5, after the installation of each long anchor cable 7 is finished, grouting into the anchor cable drill hole 6.

After the medium-length hole sublevel mining method is adopted for the inclined thick ore body, the hanging wall broken surrounding rock is pre-supported by the long anchor cable under the condition that the hanging wall broken surrounding rock influences the safe stoping of the hanging wall triangular ore body. And (3) continuously excavating the rock drilling cross drift 1 at the lower part of the segmented ore body, excavating to an upper wall rock 2 crushing zone to form an extravein tunnel 3, and pulling along the direction of the ore body to form an anchor cable fixing tunnel 4. Furthermore, a steel beam 5 is arranged in the anchor cable fixing lane 4, two ends of the steel beam 5 extend into the upper disc crushing surrounding rock for 0.5m, anchor cable drilling holes are drilled in two sides of the steel beam, a plurality of groups of double fixed anchor cables extend into the anchor cable drilling holes to fix the steel beam, so that the steel beam 5 is ensured to be firmly contacted with the upper disc surrounding rock, a better stress point is provided for the long anchor cables, and the stress limit is larger and the stress is more uniform.

And excavating upper wall surrounding rocks 2 along the rock drilling roadway 1 under each subsection ore body, and gradually reducing the height of the vein outer roadway 3 along the vein outer direction to be the same as the height of the anchor cable fixing roadway 4 excavated along the trend of the ore body when two vein outer roadways 3 which are parallel to each other and have moderate intervals are excavated, so that the excavation amount is reduced.

When the steel beam 5 is installed on the anchor cable fixing lane 4, in order to enable the steel beam 5 to be firmer, two ends of the steel beam 5 penetrate into the upper wall surrounding rock by 0.5m, a plurality of groups of anchor cable drilling holes 6 are drilled on two sides of the steel beam, a plurality of groups of double fixed anchor cables penetrate into the anchor cable drilling holes to fix the steel beam 5, and then the anchor cable drilling holes 6 are grouted by C30 concrete, so that the steel beam is firmer.

When a plurality of anchor cable drill holes 6 which are parallel to each other and are equally spaced are drilled in the ore body along the edge of the ore body, the distance between each anchor cable drill hole 6 and the edge of the rock drilling roadway 1 is smaller than the hole distance between adjacent anchor cable drill holes.

After long anchor cables 7 are arranged to penetrate anchor cable drill holes 6 in the ore body, the long anchor cables 7 pass through the vein outer roadway 3, the long anchor cables 7 are fixed on steel beams 5 of an anchor cable fixing roadway 4 end to end, and every three anchor cables are fixed together by an anchor cable fixer 10. After the long anchor cable 7 is arranged, C30 concrete is used for grouting the anchor cable drill hole 6, so that the long anchor cable 7 and an ore body are solidified into a whole and are more stable.

It is worth mentioning that one end of the root of the long anchor cable needs to be fixed in the ore body, and one end of the exposed head applies pressure to the ore body by means of prestress. The cable body material of the long anchor cable is composed of a high-strength steel strand bundle, a high-strength steel wire bundle or a thread reinforcing steel bar bundle and the like, the strength standard value of a single steel wire or a single steel strand can reach 1470MPa or higher, and when the prestress is smaller, II-grade and III-grade reinforcing steel bars are adopted, and the strength standard value is also larger than 300MPa, so that the anchoring force of the long anchor cable can reach the magnitude of meganewton. The long anchor cable has a particularly obvious supporting effect, the using conditions are simple, the anchor cable becomes a common means for treating complex geological conditions, the deep-mined rock mass has to be supported by means of the anchor cable after being damaged in a subarea, and the anchor cable has a wide application prospect.

The rock drilling roadway 1 under each subsection ore body drills an extravenal roadway 3 along the extravenal direction, the length is preferably 6m, when an anchor cable drilling hole 6 is drilled in the ore body along the edge of the ore body, the distance between the anchor cable drilling hole 6 and the edge of the ore body is preferably 1.0m, the reinforcing effect on the upper disk surrounding rock is guaranteed, and the long anchor cable and the upper disk triangular ore body are tightly combined.

Referring to fig. 1 to 4, a rock drilling roadway 1 under each sectional ore body drills an extravenal roadway 3 along the extravenal direction and excavates an anchor cable fixing roadway 4 along the trend of the ore body, and in order to reduce the excavation amount, the height of the extravenal roadway 3 is gradually reduced to be the same as the height of the anchor cable fixing roadway 4 along the extravenal direction.

Arranging steel beams 5 in the anchor cable fixing lane 4, wherein in order to ensure stability of the steel beams 5, the two sides of each steel beam are extended into the hanging wall rock by 0.5m, and the two sides of each steel beam are fixed by a plurality of groups of anchor cables extended into anchor cable holes, so that the steel beams 5 can provide better stress points for the long anchor cables 7, and the stress limit is larger.

A plurality of anchor cable drill holes 6 which are parallel to each other and are equally spaced are drilled in the ore body along the edge of the inclined ore body, the hole distances between the adjacent anchor cable drill holes 6 are the same, and the hole bottom distances of the anchor cable drill holes 6 are the same.

Long anchor cables 7 are arranged along the anchor cable drill holes 6, the head and the tail of each long anchor cable 7 are fixed on the steel beam 5, and every three long anchor cables are fixed together by an anchor cable fixer 10 near the steel beam 5. C30 concrete is injected into all anchor cable drill holes after all the long anchor cables 7 are installed, so that the long anchor cables 7, the upper-disc surrounding rock and the upper-disc triangular ore body are condensed into a whole.

The upper wall broken surrounding rock 2 and the upper wall triangular ore body form a whole by utilizing the steel beam 5 and the long anchor cable 7, so that the stability of the upper wall broken surrounding rock is greatly improved, the safety of a stope is greatly improved, and conditions are provided for realizing the safe stoping of the upper wall triangular ore body. The long anchor cables 7 are uniformly distributed in the upper plate triangular ore body, so that the upper plate broken rock body is integrally reinforced, the mining method with high stoping efficiency such as a vertical medium-length hole blasting ore-breaking method is favorably applied to stoping the upper plate triangular ore body, and the stoping efficiency of the upper plate triangular ore body is improved.

The long anchor cable pre-supporting method is adopted to reinforce the upper plate broken rock mass, so that the loss of part of ore bodies in the upper plate triangular area and dilution caused by collapse of the upper plate triangular area surrounding rock caused by the inclined ore body vertical stabilization method, the upper plate surrounding rock concrete column reinforcing method and other methods are avoided, and the complete recovery of the upper plate triangular ore body broken by the surrounding rock can be realized.