CN103498691A - Mine multiple-steel-strand combination supporting device and method - Google Patents
Mine multiple-steel-strand combination supporting device and method Download PDFInfo
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- CN103498691A CN103498691A CN201310396221.0A CN201310396221A CN103498691A CN 103498691 A CN103498691 A CN 103498691A CN 201310396221 A CN201310396221 A CN 201310396221A CN 103498691 A CN103498691 A CN 103498691A
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Abstract
The invention relates to a mine multiple-steel-strand combination supporting device and method. A guiding cap is arranged at the front end of a steel strand, a grouting pipe is arranged in the center of the steel strand, grout stopping round steel is arranged between the front end of the grouting pipe and the top end of the guiding cap, a plurality of grout discharging holes are distributed in the pipe wall of the grouting pipe, the periphery of the steel strand is provided with ring hoops from top to bottom, a steel strand sleeve is arranged on the periphery of the portion, on the free section of the supporting device, of the steel strand in a sleeved and matched mode, a lug-type sealing rubber sleeve and a circular truncated cone hole sealing rubber sleeve are arranged on the periphery of the portion, located on the sealing section of the supporting device, of the steel strand in a matched and sleeved mode, the tail end of the steel strand is fastened to a supporting board through a multi-hole lock, and a clamping piece is arranged between the steel strand and the multi-hole lock. According to the supporting device and method, the tensile strength and the shearing strength of a supporting component are improved to a great extent, the bearing capacity of deep stable surrounding rock is well utilized, and the supporting device is simple in structure and convenient to install and brings great convenience to strengthening operation of a rock layer of a broken rock zone of a mine.
Description
Technical field
the present invention relates to a kind of suspension device, especially by many steel strand combination supportings, control a kind of mining many steel strand combination supporting device and method of deformation of the surrounding rock in tunnel.
Background technology
current domestic mine mainly adopts by common mining single steel strand anchor cable or hollow grouting cable anchor the tunnel deep wall rock is reinforced.Common mining single anchor cable how by the end resin anchoring to country rock with higher pretightning force, transfer the supporting capacity of deep wall rock.The hollow grouting cable anchor generally first carries out the end resin anchoring, and stretch-draw is carried out grouting and reinforcing again and realizes full length fastening later, has high pre-stress and full length fastening characteristic concurrently.
but the deepening with mining level, deep tunnel is at residual stress, adopt under the conditions such as disturbance by force, large deformation characteristic when surrouding rock deformation shows obvious soft rock length, relaxation zone obviously increases (the local 5m of surpassing), and now common mining single anchor cable and hollow grouting cable anchor will show deficiency:
1. the length of common mining single anchor cable and hollow grouting cable anchor is generally at 6-7m, and under large relaxation zone condition, the anchor cable of finite length can not anchor into deep and stablize in rock stratum to give full play to its supporting capacity;
2. tension, the shear strength of considering single steel strand are lower, and under the compound influence of the stress of primary rock, tectonic stress, mining induced stress, common single Mine anchorage cable and hollow grouting cable anchor easily carried limit and caused and break, cut off;
3. though the hollow grouting cable anchor can carry out grouting and reinforcing to the country rock in certain limit, slip casting forms full length fastening later, and the whole limit elongation of anchor cable reduces, and can not adapt to the continuous deformation characteristic of deep weak surrounding rock;
4. the resistance to shock loads ability of common mining single anchor cable and hollow grouting cable anchor, incompatible with the Burst Tendency of deep mining.
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Summary of the invention
the problem that can not be reinforced large relaxation zone rock stratum in order to solve existing mining single steel strand anchor cable or hollow grouting cable anchor, the invention provides a kind of mining many steel strand combination supporting device and method, this suspension device and method can improve the tension of support unit largely, shear strength, also can better transfer the supporting capacity of deep stabilizing surrounding rock, the continuous deformation characteristic that can adapt to Burst Tendency and the deep wall rock of deep mining when country rock is carried out to grouting and reinforcing, and this suspension device is simple in structure, easy for installation, stronger shock loading ability is arranged, by many steel strand are carried out to synchronous tension, make many steel strand uniform stresseds, be conducive to the stability of supporting and protection structure, bring great convenience to the reinforcement of the large relaxation zone of mine rock stratum.
the technical solution adopted for the present invention to solve the technical problems is: this suspension device is divided into anchoring section from top to bottom, free segment, seal section and revealed section, this suspension device comprises guiding cap, steel strand, stifled slurry round steel, Grouting Pipe, slurry outlet, garter spring, the steel strand sleeve pipe, auricle formula seal rubber sleeve, round platform sealing of hole gum cover, supporting plate, fixing hole, intermediate plate and porous lockset, the front end of described steel strand is provided with the guiding cap of taper, the center of steel strand is provided with Grouting Pipe, the front end of Grouting Pipe is to being provided with stifled slurry round steel between the top of guiding cap, be distributed with slurry outlet on the tube wall of Grouting Pipe, the periphery of steel strand is provided with 2-4 garter spring from top to bottom, garter spring tightly binds round many steel strand around Grouting Pipe, peripheral the coincideing of steel strand that is positioned at the suspension device free segment is set with the steel strand sleeve pipe, peripheral the coincideing of steel strand that is positioned at the suspension device seal section is set with auricle formula seal rubber sleeve and round platform sealing of hole gum cover, the tail end of steel strand is fastened on supporting plate by the porous lockset, have circular fixing hole on supporting plate, during constructability by the fixing supporting plate of setscrew, be provided with intermediate plate between steel strand and porous lockset.
described anchoring section length L 1, freedom length L2, seal section length L 3 and revealed section length L 4 meet relational expression: 7m<L1+L2+L3+L4<13m, L1 ≈ (L1+L2+L3+L4)/3,150mm<L3<200mm, 150mm<L4<250mm.
described many steel strand are parallel to be arranged in around Grouting Pipe uniformly, and steel strand adopt the mining steel twisted wire, and diameter is 15.24mm-17.8mm.
described stifled slurry round steel is smooth bar, and its diameter and Grouting Pipe internal diameter are complementary, and Grouting Pipe is plastic pipe.
described slurry outlet is distributed in noncontact place of steel strand and Grouting Pipe, the distribution of slurry outlet by free segment to anchoring section density gradually.
described auricle formula seal rubber sleeve and round platform sealing of hole gum cover all have elasticity preferably, and all punching has slip casting pore I and steel strand hole I, and slip casting pore I size is less than the external diameter of Grouting Pipe, so that permanent position; Steel strand hole I size is less than the diameter of steel strand, so that permanent position, steel strand hole I is uniformly distributed in around slip casting pore I.
described supporting plate upper punch has slip casting pore II and steel strand hole II, and the size of slip casting pore II is greater than the external diameter of Grouting Pipe, in order to install; The size of steel strand hole II is greater than the diameter of steel strand, in order to install, steel strand hole II be uniformly distributed in slip casting pore II around.
this is mining, and its job practices of many steel strand combination supporting device is:
1. the design of many steel strand combination supporting device and processing; According to the actual state for the treatment of the reinforced roadway country rock, determine the radical of required drilling depth L, required steel strand, and then jointly determining the diameter R of construction drill according to steel strand radical and each drill bit of drilling machine size model, bore diameter R should get little under the prerequisite met the demands as far as possible; Design and process corresponding many steel strand combination supporting device according to drilling depth L and diameter R, each size meets: 7m<L1+L2+L3+L4<13m, L1 ≈ (L1+L2+L3+L4)/3,150mm<L3<200mm, 150mm<L4<250mm, L-(L1+L2+L3) ≈ 100mm;
2. the installation of drilling construction and many steel strand combination supporting device; Size and orientation construction drill according to design, after drilling construction completes, guiding cap is stretched in boring, at the bottom of relying on manpower progressively many steel strand combination supporting device to be pushed into to hole, and auricle formula seal rubber sleeve and round platform sealing of hole gum cover are clamp-oned in hole, make the large end face of round platform sealing of hole gum cover concordant with the country rock surface, rapidly supporting plate is close to country rock through the exposed junction of steel strand, at the country rock place construction drill corresponding with fixing hole so that fixedly supporting plate of setscrew to be installed, during this period, should utilize temporary lining equipment to withstand supporting plate, in case the device landing;
3. slip casting; Grouting pipeline and Grouting Pipe are connected and started slip casting, and grouting pressure stops slip casting after surpassing 6MPa;
4. stretch-draw and locking; After slip casting completes one week, by anchor cable tensioning machine tool, many steel strand are carried out to synchronous tension, by clip type porous lockset, lock many steel strand simultaneously.
the invention has the beneficial effects as follows, this suspension device and method can improve tension, the shear strength of support unit largely, also can better transfer the supporting capacity of deep stabilizing surrounding rock, the continuous deformation characteristic that can adapt to Burst Tendency and the deep wall rock of deep mining when country rock is carried out to grouting and reinforcing, and this suspension device is simple in structure, easy for installation, stronger shock loading ability is arranged; By many steel strand are carried out to synchronous tension, make many steel strand uniform stresseds, be conducive to the stability of supporting and protection structure, bring great convenience to the reinforcement of the large relaxation zone of mine rock stratum.
The accompanying drawing explanation
below in conjunction with accompanying drawing and example, the invention will be further described.
fig. 1 is structural principle schematic diagram of the present invention.
in Fig. 1,1. guiding cap, 2. steel strand, 3. stifled slurry round steel, 4. Grouting Pipe, 5. slurry outlet, 6. garter spring, 7. steel strand sleeve pipe, 8. hole wall, 9. auricle formula seal rubber sleeve, 10. round platform sealing of hole gum cover, 11. supporting plates, 12. fixing holes, 13. intermediate plates, 14. porous locksets.
The specific embodiment
in Fig. 1, this suspension device is divided into anchoring section from top to bottom, free segment, seal section and revealed section, this suspension device comprises guiding cap 1, steel strand 2, stifled slurry round steel 3, Grouting Pipe 4, slurry outlet 5, garter spring 6, steel strand sleeve pipe 7, auricle formula seal rubber sleeve 9, round platform sealing of hole gum cover 10, supporting plate 11, fixing hole 12, intermediate plate 13 and porous lockset 14, the front end of described steel strand 2 is provided with the guiding cap 1 of taper, the center of steel strand 2 is provided with Grouting Pipe 4, the front end of Grouting Pipe 4 is to being provided with stifled slurry round steel 3 between the top of guiding cap 1, be distributed with slurry outlet 5 on the tube wall of Grouting Pipe 4, the periphery of steel strand 2 is provided with 2-4 garter spring 6 from top to bottom, garter spring 6 tightly binds round many steel strand 2 around Grouting Pipe 4, peripheral the coincideing of steel strand 2 that is positioned at the suspension device free segment is set with steel strand sleeve pipe 7, peripheral the coincideing of steel strand 2 that is positioned at the suspension device seal section is set with auricle formula seal rubber sleeve 9 and round platform sealing of hole gum cover 10, the tail end of steel strand 2 is fastened on supporting plate 11 by porous lockset 14, have circular fixing hole 12 on supporting plate 11, during constructability by the fixing supporting plate 11 of setscrew, be provided with intermediate plate 13 between steel strand 2 and porous lockset 14.
described anchoring section length L 1, freedom length L2, seal section length L 3 and revealed section length L 4 meet relational expression: 7m<L1+L2+L3+L4<13m, L1 ≈ (L1+L2+L3+L4)/3,150mm<L3<200mm, 150mm<L4<250mm.
described many steel strand 2 are parallel to be arranged in around Grouting Pipe 4 uniformly, and steel strand 2 adopt the mining steel twisted wire, and diameter is 15.24mm-17.8mm.
described stifled slurry round steel 3 is smooth bar, and its diameter and Grouting Pipe 4 internal diameters are complementary, and Grouting Pipe 4 is plastic pipe.
described slurry outlet 5 is distributed in noncontact place of steel strand 2 and Grouting Pipe 4, the distribution of slurry outlet 5 by free segment to anchoring section density gradually.
described auricle formula seal rubber sleeve 9 and round platform sealing of hole gum cover 10 all have elasticity preferably, and all punching has slip casting pore I and steel strand hole I, and slip casting pore I size is less than the external diameter of Grouting Pipe 4, so that permanent position; Steel strand hole I size is less than the diameter of steel strand 2, so that permanent position, steel strand hole I is uniformly distributed in around slip casting pore I.
described supporting plate 11 upper punches have slip casting pore II and steel strand hole II, and the size of slip casting pore II is greater than the external diameter of Grouting Pipe 4, in order to install; The size of steel strand hole II is greater than the diameter of steel strand 2, in order to install, steel strand hole II be uniformly distributed in slip casting pore II around.
this is mining, and its job practices of many steel strand combination supporting device is:
1. the design of many steel strand combination supporting device and processing; According to the actual state for the treatment of the reinforced roadway country rock, determine the radical of required drilling depth L, required steel strand 2, and then jointly determining the diameter R of construction drill according to steel strand 2 radicals and each drill bit of drilling machine size model, bore diameter R should get little under the prerequisite met the demands as far as possible; Design and process corresponding many steel strand combination supporting device according to drilling depth L and diameter R, each size meets: 7m<L1+L2+L3+L4<13m, L1 ≈ (L1+L2+L3+L4)/3,150mm<L3<200mm, 150mm<L4<250mm, L-(L1+L2+L3) ≈ 100mm;
2. the installation of drilling construction and many steel strand combination supporting device, size and orientation construction drill according to design, after drilling construction completes, guiding cap 1 is stretched in boring, at the bottom of relying on manpower progressively many steel strand combination supporting device to be pushed into to hole, and auricle formula seal rubber sleeve 9 and round platform sealing of hole gum cover 10 are clamp-oned in hole, make the large end face of round platform sealing of hole gum cover 10 concordant with the country rock surface, rapidly supporting plate 11 is close to country rock through the exposed junction of steel strand 2, at the country rock place construction drill corresponding with fixing hole 12 so that fixedly supporting plate 11 of setscrew to be installed, during this period, should utilize temporary lining equipment to withstand supporting plate 11, in case device landing,
3. slip casting; Grouting pipeline and Grouting Pipe 4 are connected and started slip casting, and grouting pressure stops slip casting after surpassing 6MPa;
4. stretch-draw and locking; After slip casting completes one week, by anchor cable tensioning machine tool, many steel strand 2 are carried out to synchronous tension, by clip type porous lockset 14, lock many steel strand 2 simultaneously.
Claims (5)
1. mining many steel strand combination supporting device and method, this suspension device is divided into anchoring section from top to bottom, free segment, seal section and revealed section, this suspension device comprises guiding cap (1), steel strand (2), stifled slurry round steel (3), Grouting Pipe (4), slurry outlet (5), garter spring (6), steel strand sleeve pipe (7), auricle formula seal rubber sleeve (9), round platform sealing of hole gum cover (10), supporting plate (11), fixing hole (12), intermediate plate (13) and porous lockset (14), it is characterized in that, the front end of described steel strand (2) is provided with the guiding cap (1) of taper, the center of steel strand (2) is provided with Grouting Pipe (4), the front end of Grouting Pipe (4) is to being provided with stifled slurry round steel (3) between the top of guiding cap (1), be distributed with slurry outlet (5) on the tube wall of Grouting Pipe (4), the periphery of steel strand (2) is provided with 2-4 garter spring (6) from top to bottom, garter spring (6) tightly binds round many steel strand (2) around Grouting Pipe (4), peripheral the coincideing of steel strand (2) that is positioned at the suspension device free segment is set with steel strand sleeve pipe (7), peripheral the coincideing of steel strand (2) that is positioned at the suspension device seal section is set with auricle formula seal rubber sleeve (9) and round platform sealing of hole gum cover (10), the tail end of steel strand (2) is fastened on supporting plate (11) by porous lockset (14), have circular fixing hole (12) on supporting plate (11), during constructability by the fixing supporting plate (11) of setscrew, be provided with intermediate plate (13) between steel strand (2) and porous lockset (14).
2. a kind of mining many steel strand combination supporting device and method according to claim 1, it is characterized in that, described anchoring section length L 1, freedom length L2, seal section length L 3 and revealed section length L 4 meet relational expression: 7m<L1+L2+L3+L4<13m, L1 ≈ (L1+L2+L3+L4)/3,150mm<L3<200mm, 150mm<L4<250mm.
3. a kind of mining many steel strand combination supporting device and method according to claim 1, it is characterized in that, described many steel strand (2) are parallel is arranged in Grouting Pipe (4) on every side uniformly, and steel strand (2) adopt the mining steel twisted wire, and diameter is 15.24mm-17.8mm.
4. a kind of mining many steel strand combination supporting device and method according to claim 1, is characterized in that, described stifled slurry round steel (3) is smooth bar, and its diameter and Grouting Pipe (4) internal diameter is complementary, and Grouting Pipe (4) is plastic pipe.
5. a kind of mining many steel strand combination supporting device and method according to claim 1, it is characterized in that, described slurry outlet (5) is distributed in noncontact place of steel strand (2) and Grouting Pipe (4), the distribution of slurry outlet (5) by free segment to anchoring section density gradually.
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| CN201310396221.0A CN103498691B (en) | 2013-09-04 | 2013-09-04 | A kind of mining many steel strand combination supporting device and method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104500045A (en) * | 2014-12-15 | 2015-04-08 | 中铁第四勘察设计院集团有限公司 | Ground temperature test method for drilling grouting in deeply buried chamber |
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| US5984588A (en) * | 1997-03-07 | 1999-11-16 | Marcegaglia S.P.A. | Method for the stabilization of rock masses and related stabilization element |
| CN2504316Y (en) * | 2001-09-18 | 2002-08-07 | 柳州市建筑机械总厂 | Pile plate anchorage cable |
| CN101148877A (en) * | 2007-10-16 | 2008-03-26 | 中国京冶工程技术有限公司 | Multistage bag-type compression anchor bar |
| CN101798812A (en) * | 2010-04-19 | 2010-08-11 | 北京科技大学 | Double anchoring section prestressed anchoring system with three-layer protection and anchoring method thereof |
| CN202144593U (en) * | 2011-07-04 | 2012-02-15 | 北京鑫实路桥建设有限公司 | Bundling prestressing steel strand anchor cable for strengthening road rock slope |
| CN202926355U (en) * | 2012-10-31 | 2013-05-08 | 于守东 | Hollow grouting anchor cable for mine |
-
2013
- 2013-09-04 CN CN201310396221.0A patent/CN103498691B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5984588A (en) * | 1997-03-07 | 1999-11-16 | Marcegaglia S.P.A. | Method for the stabilization of rock masses and related stabilization element |
| CN2504316Y (en) * | 2001-09-18 | 2002-08-07 | 柳州市建筑机械总厂 | Pile plate anchorage cable |
| CN101148877A (en) * | 2007-10-16 | 2008-03-26 | 中国京冶工程技术有限公司 | Multistage bag-type compression anchor bar |
| CN101798812A (en) * | 2010-04-19 | 2010-08-11 | 北京科技大学 | Double anchoring section prestressed anchoring system with three-layer protection and anchoring method thereof |
| CN202144593U (en) * | 2011-07-04 | 2012-02-15 | 北京鑫实路桥建设有限公司 | Bundling prestressing steel strand anchor cable for strengthening road rock slope |
| CN202926355U (en) * | 2012-10-31 | 2013-05-08 | 于守东 | Hollow grouting anchor cable for mine |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104500045A (en) * | 2014-12-15 | 2015-04-08 | 中铁第四勘察设计院集团有限公司 | Ground temperature test method for drilling grouting in deeply buried chamber |
| CN104500045B (en) * | 2014-12-15 | 2018-03-27 | 中铁第四勘察设计院集团有限公司 | A kind of geothermal test method of deep cavern internal drilling slip casting |
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Inventor after: Li Guichen Inventor after: Zhang Nong Inventor after: Sun Yuantian Inventor after: Gao Kai Inventor after: Han Changliang Inventor after: Sun Hui Inventor after: Wei Yinghao Inventor after: Jiang Zuohan Inventor before: Li Guichen Inventor before: Sun Hui Inventor before: Wei Yinghao Inventor before: Zhang Nong Inventor before: Jiang Zuohan Inventor before: Han Changliang |
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