CN203584447U - Anti-impact interval grouting anchor cable - Google Patents
Anti-impact interval grouting anchor cable Download PDFInfo
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- CN203584447U CN203584447U CN201320763045.5U CN201320763045U CN203584447U CN 203584447 U CN203584447 U CN 203584447U CN 201320763045 U CN201320763045 U CN 201320763045U CN 203584447 U CN203584447 U CN 203584447U
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- grouting
- hinge line
- steel hinge
- anchor
- slip casting
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Abstract
The utility model discloses an anti-impact interval grouting anchor cable. The anti-impact interval grouting anchor cable comprises a one-way grouting valve, a hollow grouting stranded steel wire, an arc-shaped anchoring ring, a sliding yielding retraction ring, a conical stop-grouting plug and a segmented sealing plug, wherein the sliding yielding retraction ring is arranged between the arc-shaped anchoring ring and the conical stop-grouting plug, grout outlet valves are arranged on a flexible grouting pipe in the hollow grouting stranded steel wire at an interval of a certain length, the segmented sealing plug is arranged at the front end of an expansion area of the stranded steel wire, and interval grouting is realized. According to the anti-impact interval grouting anchor cable, a grouting section L2n-1 and a non-grouting section L2n are arranged according to the conditions of surrounding rock, the stress state of a supporting system is improved scientifically, the instantaneous high-stress state of the stranded steel wire of an anchoring section caused by intense deformation of the surrounding rock is relieved, the stranded steel wire is prevented from breaking, and the utilization rate of the anchor cable is improved.
Description
Technical field
The utility model relates to a kind of for support engineering grouting cable anchors such as ground, water conservancy, mines.
Background technology
Anchor cable is because its anchorage depth is large, supporting capacity is high and can apply larger pretightning force, thereby can obtain more satisfactory supporting effect.In actual applications, conventionally adopt Bolt-rope Support mode, at the roadway support initial stage, take the flexible support of anchor pole as main, the later stage be take the suspension function of anchor cable as main, and both learn from other's strong points to offset one's weaknesses, and have given full play to anchor pole, anchor cable integer support performance.But the high seam workings subject to dy namic pressure in less stable, such as gob side entry driving, large Cross-section Cut, be subject to roadway influenced by overhead mining that dynamic pressure affects etc., because anchorage length is only 1/3 of anchor cable length, its supporting capacity is on the low side, limited to the reinforcement effect of broken top coal, therefore, on the basis of anchor cable, developed hollow grouting cable anchor, slip casting anchoring anchor cable and resin anchoring anchor cable are united two into one, learn from other's strong points to offset one's weaknesses, realized full length fastening.In recent years, follow the increase of coal mining intensity, seam mining develops in depth, the complicated mechanical environment of deep rock mass excavation in typical high-ground stress, High-geotemperature, high karst hydraulic pressure, mechanical equivalent of light excavation energetic disturbance, coal and rock has stronger rheology, creep properties, dilatancy is outstanding, and distortion has impact.After supporting completes, anchor pole, anchor cable form the anchoring body that intensity is higher around, but the support system between anchor pole, anchor cable is difficult to accomplish to coordinate completely, particularly high-ground stress environment and coal and rock are out of shape saltation zone, due to anchor cable steel strand rigidity compared with large, elongation per unit length is little, in the supporting later stage, anchor cable body bears higher tensile stress vertically, when acutely being increased along horizontal distortion by supported laneway rock stratum, anchor cable body when tension state radially allow pressure energy power a little less than, anchor cable body is very easily cut off, and makes it lose support capacity, and roof accident occurs.Therefore, the problem existing in deep-well roadway with large deformation support system for anchor cable, grouting cable anchor, be badly in need of a kind of novel anchor cable structure and supporting method, improve anchor cable and allow pressure energy power in support system, realize " allow by force complementation " of cable bolting system, for the supporting problem that solves deep-well roadway with large deformation, provide effective theory and technical support.
Utility model content
In order to solve the problem existing when grouting cable anchor is applied to the supporting of deep-well roadway with large deformation, the utility model provides a kind of protecting against shock interval grouting cable anchor, by the innovation of grouting cable anchor structure, in anchor hole, realize interval slip casting, do not reducing on the basis of supporting intensity, make every a segment distance, to form " non-slip casting section " in cable bolting system, according to supporting region Mechanics Parameters of Rock Mass design " non-slip casting section " length L
2nat " non-slip casting section " anchor cable body, can in anchor hole, realize the Bending Rotation of certain angle, when being deformed violent increase suddenly by supported laneway rock mass, the rotation of " non-slip casting section " interior anchor cable body and the crooked moment stress concentration degree of having alleviated anchorage cable anchoring height stressed zone, avoided to a certain extent anchor cable body moment to be cut off phenomenon and occurred.
For solving the problems of the technologies described above, the technical solution adopted in the utility model is: the utility model provides a kind of protecting against shock interval grouting cable anchor, comprise unidirectional grout valve, hollow slip casting steel hinge line, arc anchor ring, slide to allow and press contractile ring, taper stop grouting plug, segmented seal plug, described unidirectional grout valve is arranged on hollow slip casting steel hinge line afterbody, for one-way high-pressure slip casting, arc anchor ring, slip are provided with through hole in the middle of allowing and pressing contractile ring, taper stop grouting plug, segmented seal plug, and hollow slip casting steel hinge line passes along through hole.
Described hollow slip casting steel hinge line is comprised of hollow steel hinge line, flexible grout pipe and steel hinge line expansion loop, hollow steel hinge line arranges steel hinge line expansion loop at interval of certain length, steel hinge line is expanded and scatter, flexible grout pipe passes along steel hinge line center, needs the anchoring section L of slip casting according to working design
2n-1(n=1,2 ..., n) position, at steel hinge line, expanding to scatter arranges slurry-supplying valve, at " non-slip casting section " L
2n(n=1,2 ..., n) position is without slurry-supplying valve is set.
Described arc anchor ring one end is globoidal structure, contacts with arc pallet, and arc anchor ring inside is cone structure, the inner cone-shaped clip of installing.
Described slip allows presses contractile ring be allowed and pressed contractile ring, arc pallet to form by arc pallet, elasticity, arc pallet one end is made as cambered surface, contact with arc anchor ring cambered surface, the other end is made as plane, allows and presses contractile ring to be connected with elasticity, and arc pallet one end is plane, be connected with elastic shrinkage ring, the other end is arc, and centre is plane, is connected with taper stop grouting plug.
Described taper stop grouting plug center is provided with through hole, and hollow slip casting steel hinge line passes from through hole, and overall structure is taper, and one end is made as plane, is connected with arc pallet, and the other end is the conical surface, is arranged in anchor hole.
Described segmented seal plug integral body is cylindric or taper, and center is provided with through hole, is arranged on the steel hinge line position front end that scatters that expands, and according to slip casting section design attitude, along steel hinge line axis direction, steel hinge line is divided into some sections in the expansion position of scattering.
By application a kind of protecting against shock of the utility model interval grouting cable anchor, according to wall rock condition, " slip casting section " L is set
2n-1" non-slip casting section " L
2nquantity, position and length, in slip casting section, grouting pressure can be designed to 2MPa～8MPa, by improving grouting pressure, slurries is spread around in rock fracture to boring, and country rock is played to adhesive solidification effect, has greatly strengthened slip casting section L
2n-1interval anchored force, has improved anchor and has noted interval bulk strength, the improvement of science the force-bearing situation of support system.When country rock body, along anchor cable, moment greater impact distortion axially occurs, slide to allow and press contractile ring pressurized to shrink along anchor cable to slide, can effectively alleviate the country rock moment impact effect to anchor cable vertically; When being moved perpendicular to anchor cable axis direction by edge, upper and lower rock stratum, supporting region, conventional anchor cable is pressed space without allowing, at interface place, rock stratum, form stronger shear stress, anchor cable body is easily cut off, and loses support capacity, when adopting interval grouting cable anchor, when rock stratum interface is when " non-slip casting section ", because " non-slip casting section " allows, press the existence in space, anchor cable can rotate freely movement in anchor hole, has effectively avoided anchor cable to bear the high shear stress state of moment.Application protecting against shock interval grouting cable anchor, alleviated the anchoring section steel hinge line moment high-stress state causing because of country rock drastic deformation, realize cable bolting system " allow by force complementation " theory, for the supporting problem that solves deep-well roadway with large deformation, provide effective technological means.
Accompanying drawing explanation
Fig. 1 is the structural representation of the utility model duty;
Fig. 2 is the utility model protecting against shock interval grouting cable anchor structure chart;
Fig. 3 is A-A partial sectional view in the middle of Fig. 2;
Fig. 4 is that the utility model is alleviated by supporting country rock along the axial moment large deformation of anchor cable schematic diagram;
Fig. 5 is conventional cable bolting strata movement anchorage cable stress state analysis chart;
Fig. 6 is that the utility model cable bolting strata movement anchorage cable stress state is analyzed legend 1;
Fig. 7 is that the utility model cable bolting strata movement anchorage cable stress state is analyzed legend 2.
The specific embodiment
As shown in FIG. 1 to 3, a kind of protecting against shock of the utility model interval grouting cable anchor, comprise unidirectional grout valve 1, hollow slip casting steel hinge line 2, arc anchor ring 3, slide to allow and press contractile ring 4, taper stop grouting plug 5, segmented seal plug 6, described unidirectional grout valve 1 is arranged on hollow slip casting steel hinge line afterbody, for one-way high-pressure slip casting, arc anchor ring 3, slip are provided with through hole in the middle of allowing and pressing contractile ring 4, taper stop grouting plug 5, segmented seal plug 6, and hollow slip casting steel hinge line 2 passes along through hole.Hollow slip casting steel hinge line 2 is comprised of flexible grout pipe 14, hollow steel hinge line 15 and steel hinge line expansion loop 16, hollow steel hinge line 15 arranges steel hinge line expansion loop 16 at interval of certain length, steel hinge line is expanded to scatter, flexible grout pipe 14 passes along steel hinge line center, needs the anchoring section L of slip casting according to working design
2n-1(n=1,2 ..., n) position, arranges slurry-supplying valve 17 in the expand position of scattering of steel hinge line, at " non-slip casting section " L
2n(n=1,2 ..., n) position is without slurry-supplying valve is set.Arc anchor ring 3 one end are globoidal structure 10, contact with arc pallet 11 cambered surfaces, and arc anchor ring 3 inside are cone structure, the inner cone-shaped clip 9 of installing.Slip allows presses contractile ring 4 be allowed and pressed contractile ring 12, arc pallet 13 to form by arc pallet 11, elasticity, arc pallet 11 one end are made as cambered surface, contact with arc anchor ring cambered surface 10, the other end is made as plane, allows and presses contractile ring 12 to be connected with elasticity, and arc pallet 13 one end are plane, allow and press contractile ring 12 to be connected with elasticity, the other end is arc, and centre is plane, is connected with taper stop grouting plug 5.Taper stop grouting plug 5 centers are provided with through hole, and hollow slip casting steel hinge line 2 passes from through hole, and overall structure is taper, one end is made as plane, be connected with arc pallet 13, the other end is the conical surface, is arranged in anchor hole, taper stop grouting plug 5 adopts flexible material processing, requirement has certain intensity, has collapsed seal performance simultaneously, to guarantee the sealing in slip casting aperture, while preventing slip casting, slurries flow out along aperture.Segmented seal plug 6 integral body are cylindric or taper, and center is provided with through hole, are arranged on steel hinge line position 18 front ends that scatter that expand, and according to slip casting section design attitude, along steel hinge line axis direction, steel hinge line are divided into some sections in the expansion position of scattering.
A protecting against shock interval grouting cable anchor, using method comprises the following steps:
1.. the roof strata coring to job location, test its rock mechanics parameters, according to test result, determine interval grouting cable anchor " slip casting section " L
2n-1length and " non-slip casting section " L
2nlength is processing protecting against shock interval, job location grouting cable anchor accordingly.With reference to Fig. 1, in " slip casting section " length L
2n-1the expand position of scattering of interval steel hinge line arranges slurry-supplying valve, in " non-slip casting section " length L
2ninterval steel hinge line expands and scatters position without slurry-supplying valve is set, to realize interval slip casting;
2. prepare injecting paste material, injecting paste material be take cement paste as main, add cement injection additive simultaneously, comprise early strength admixture, pumping admixture, super plasticizer, expansion agent etc., make injecting paste material have good morning strong with high-strength performance, good mobility and micro-expansibility, thereby greatly improve the effect of anchor pouring reinforcement;
3.. application jumbolter is pressed design attitude construction anchor cable hole, while helping to construct anchor cable hole for the frangible top board of weakness or two, easily piles up broken coal landwaste in anchor cable hole, has constructed after anchor hole, cleans out disintegrating slag and bore position, is convenient to sealing of hole;
4. resin anchoring agent is pushed to boring with interval grouting cable anchor, in position, anchor hole aperture, carry out encapsulation process, application jumbolter stirs well in hole, complete after the anchoring of anchor cable initial stage, wait for after 30 min left and right reach anchoring strength taper stop grouting plug 5 is installed, load onto taper stop grouting plug 5, slide to allow and press contractile ring 4 and arc anchor ring 3, then carry out stretch-draw pretension;
5. be ready to injecting paste material and grouting pump 7, by Grouting Pipe, be connected with protecting against shock interval grouting cable anchor afterbody unidirectional grout valve 1, start grouting pump 7 and carry out slip casting, injection speed is wanted slowly, during slip casting, note observing pressure meter, when pressure meter 8 has rising trend, wait for slip casting again in 2～3 minutes, to guarantee slip casting section L
2n-1slurries body can be filled with in interval, in order to obtain better supporting effect, as required, grouting pressure can be designed to 2MPa～8MPa, improves grouting pressure, and slurries are around spread in rock fracture to boring, country rock is played to adhesive solidification effect, strengthen slip casting section L
2n-1interval anchored force, improves anchor and notes interval bulk strength.
Introducing below when the utility model is implemented prevents country rock large deformation and moment impact to cause principle and the engineering that anchor cable destroys to apply the problem of noting:
With reference to Fig. 4, after supporting completes, for the weak surrounding rock body by supporting under high-ground stress environment, along anchor cable, axially easily there is moment greater impact distortion, due to anchor cable steel strand rigidity compared with large, elongation per unit length is little, probably, under the percussion of country rock body, anchor ring comes off or impact force has surpassed the tensile strength of steel strand and occur disrumpent feelings.When adopting the utility model protecting against shock interval grouting cable anchor; when axially there is moment greater impact distortion along anchor cable in country rock body; slip allows presses contractile ring 4 pressurizeds to be punctured into 19 shapes, has effectively alleviated country rock moment impact effect vertically, indirect protection anchor cable.
With reference to Fig. 5, for conventional resin anchoring or slip casting anchoring, anchor cable and surrounding rock body interact and form the region of high stress, and anchor cable body bears higher tensile stress vertically, when being increased perpendicular to the distortion of anchor cable axis direction is violent by edge, upper and lower rock stratum, supporting region, thickness is h
1rock stratum when moving horizontally displacement and being a, anchor cable forms stronger shear stress at rock stratum interface 20 places, because anchor cable is in the region of high stress, without allowing, press space, and anchor cable body when tension state radially allow pressure energy power a little less than, anchor cable body is very easily cut off, and makes it lose support capacity, and roof accident occurs.When adopting the utility model protecting against shock interval grouting cable anchor, with reference to Fig. 6, same thickness is h
1rock stratum when moving horizontally displacement and being a, when rock stratum interface is when " non-slip casting section " region approaches centre position, anchor cable forms less flexural deformation in " non-slip casting section " and " slip casting section " intersection 21,23, because allowing, " non-slip casting section " press the existence in space, anchor cable can rotate freely movement in anchor hole, under this condition, the anchor cable in " non-slip casting section " space is not subject to rock stratum shearing at interface place, rock stratum, has effectively avoided anchor cable to bear the high shear stress state of moment; With reference to Fig. 7, when bottom, moving depth of stratum is h
2(h
2<h
1) rock stratum when moving horizontally displacement and being a, rock stratum interface is in " non-slip casting section " region during near position, rock stratum, bottom, anchor cable is in " non-slip casting section " and the less flexural deformation of the same formation of " slip casting section " intersection 24,26, anchor cable in " non-slip casting section " space has been subject to rock stratum shearing at rock stratum interface 25, but compare Fig. 5 situation, because " non-slip casting section " allows, press the existence in space, anchor cable high shear stress state has obtained effective alleviation.
Visible, strata movement interface also has larger impact in " non-slip casting section " residing position, region for the stress of anchor cable, and rock stratum plane of weakness, destructible moving area and strata movement angle are non-linear strong in Practical Project, be difficult to judgement, therefore, in actual applications, roof strata coring that must be to job location, test rock mechanics parameters and top board layering situation, arrange " slip casting section " L according to test result science
2n-1" non-slip casting section " L
2nlength and location, to guarantee the optimization of interval grouting program and good effect, realize cable bolting system " allow by force complementation " theory, for the supporting problem that solves deep-well roadway with large deformation, provide effective technical equipment support.
Claims (6)
1. a protecting against shock interval grouting cable anchor, comprise unidirectional grout valve, hollow slip casting steel hinge line, arc anchor ring, slide to allow and press contractile ring, taper stop grouting plug, segmented seal plug, it is characterized in that: described unidirectional grout valve is arranged on hollow slip casting steel hinge line afterbody, for one-way high-pressure slip casting, arc anchor ring, slip are provided with through hole in the middle of allowing and pressing contractile ring, taper stop grouting plug, segmented seal plug, and hollow slip casting steel hinge line passes along through hole.
2. a kind of protecting against shock according to claim 1 interval grouting cable anchor, it is characterized in that: described hollow slip casting steel hinge line is comprised of hollow steel hinge line, flexible grout pipe and steel hinge line expansion loop, hollow steel hinge line arranges steel hinge line expansion loop at interval of certain length, steel hinge line is expanded to scatter, flexible grout pipe passes along steel hinge line center, needs the anchoring section L of slip casting according to working design
2n-1(n=1,2 ..., n) position, arranges slurry-supplying valve in the expand position of scattering of steel hinge line, at " non-slip casting section " L
2n(n=1,2 ..., n) position is without slurry-supplying valve is set.
3. a kind of protecting against shock according to claim 1 interval grouting cable anchor, is characterized in that: described arc anchor ring one end is globoidal structure, contacts with arc pallet, and arc anchor ring inside is cone structure, the inner cone-shaped clip of installing.
4. a kind of protecting against shock according to claim 1 interval grouting cable anchor, it is characterized in that: described slip allows presses contractile ring be allowed and pressed contractile ring, arc pallet to form by arc pallet, elasticity, arc pallet one end is made as cambered surface, contacts with arc anchor ring cambered surface, and the other end is made as plane, allow and press contractile ring to be connected with elasticity, arc pallet one end is plane, is connected with elastic shrinkage ring, and the other end is arc, centre is plane, is connected with taper stop grouting plug.
5. a kind of protecting against shock according to claim 1 interval grouting cable anchor, is characterized in that: described taper stop grouting plug center is provided with through hole, and hollow slip casting steel hinge line passes from through hole, overall structure is taper, and one end is made as plane, is connected with arc pallet, the other end is the conical surface, is arranged in anchor hole.
6. a kind of protecting against shock according to claim 1 interval grouting cable anchor, it is characterized in that: described segmented seal plug integral body is cylindric or taper, center is provided with through hole, be arranged on the steel hinge line position front end that scatters that expands, according to slip casting section design attitude, along steel hinge line axis direction, steel hinge line is divided into some sections in the expansion position of scattering.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320763045.5U CN203584447U (en) | 2013-11-28 | 2013-11-28 | Anti-impact interval grouting anchor cable |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320763045.5U CN203584447U (en) | 2013-11-28 | 2013-11-28 | Anti-impact interval grouting anchor cable |
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| Publication Number | Publication Date |
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| CN203584447U true CN203584447U (en) | 2014-05-07 |
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|---|---|---|---|
| CN201320763045.5U Expired - Fee Related CN203584447U (en) | 2013-11-28 | 2013-11-28 | Anti-impact interval grouting anchor cable |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103590845A (en) * | 2013-11-28 | 2014-02-19 | 河南理工大学 | Impact-resistant interval grouting anchor cable and use method thereof |
| CN109441510A (en) * | 2018-12-28 | 2019-03-08 | 常州工学院 | A kind of impact tunnel segmentation anchoring anchor cable |
| CN109519176A (en) * | 2019-01-28 | 2019-03-26 | 粤水电轨道交通建设有限公司 | Rich water granite residual soil stratum Tunneling by mining method grouting strengthening method and structure |
| CN112663605A (en) * | 2020-12-17 | 2021-04-16 | 山东建筑大学 | Anchoring device, pre-stressed anchoring structure and construction method thereof |
-
2013
- 2013-11-28 CN CN201320763045.5U patent/CN203584447U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103590845A (en) * | 2013-11-28 | 2014-02-19 | 河南理工大学 | Impact-resistant interval grouting anchor cable and use method thereof |
| CN103590845B (en) * | 2013-11-28 | 2015-09-16 | 河南理工大学 | A kind of Impact-resistant interval grouting cable anchor and using method thereof |
| CN109441510A (en) * | 2018-12-28 | 2019-03-08 | 常州工学院 | A kind of impact tunnel segmentation anchoring anchor cable |
| CN109519176A (en) * | 2019-01-28 | 2019-03-26 | 粤水电轨道交通建设有限公司 | Rich water granite residual soil stratum Tunneling by mining method grouting strengthening method and structure |
| CN112663605A (en) * | 2020-12-17 | 2021-04-16 | 山东建筑大学 | Anchoring device, pre-stressed anchoring structure and construction method thereof |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140507 Termination date: 20151128 |