CN101929347A - Coordinated-deformation energy-absorption anchor rod suitable for mining high-stress large-deformation rock mass - Google Patents
Coordinated-deformation energy-absorption anchor rod suitable for mining high-stress large-deformation rock mass Download PDFInfo
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- CN101929347A CN101929347A CN 201010254537 CN201010254537A CN101929347A CN 101929347 A CN101929347 A CN 101929347A CN 201010254537 CN201010254537 CN 201010254537 CN 201010254537 A CN201010254537 A CN 201010254537A CN 101929347 A CN101929347 A CN 101929347A
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Abstract
The invention discloses a coordinated-deformation energy-absorption anchor rod suitable for mining a high-stress large-deformation rock mass. The rod body of the anchor rod mainly comprises an elongated anchoring section straight rod body (1) and an energy-absorption section bending rod body (2), wherein one end, close to the energy-absorption section bending rod body, of the rod body is provided with a threaded section (5); a fastening nut (4) is screwed on the threaded section (5); and a steel pallet (3) is sleeved between the fastening nut (4) on the threaded section (5) and the energy-absorption section bending rod body. The anchor rod is mainly characterized in that: a wavelike bending energy-absorption section in a specific length and a specific shape is mechanized on a long straight threaded steel rod body in a heat treatment mode; the energy-adsorption section restrictively allows a wall rock to deform properly and simultaneously absorb the deformation energy of the rock mass until reaching total allowable deformation quantity meeting a design requirement. In the process, the supporting force of the anchor rod is increased gradually; and finally, after the bending section is completely straightened and a yielding effect controlled by a high-stress roadway ground pressure is achieved, the anchor rod becomes a high-strength rigid resin anchor rod for providing greater supporting force for a supported wall rock mass.
Description
Technical field
The present invention relates to a kind of mining anchor pole, particularly relate to a kind of mining compatible deformation energy-absorption anchor rod that is applicable to heavily stressed large deformation rock mass, belong to sub-terrain mines mountain region pressure-controlled and roadway support technical field.
Background technology
Bolt support technology is the history in existing more than 100 year so far, has become underground engineering construction a kind of more novel support technology commonly used.Bolt support has many advantages: can significantly improve the roadway support effect, increase degree of safety, save steel, reduce support cost, reduce labor intensity, improve working environment at coal mines, and maintenance cost be low, it is light to construct etc.At present, often adopt rigidity anchor pole (as twisted steel anchor rod) in the underground hard rock of superficial part mine, with mortar or resin anchoring, this anchor pole rigidity is big, the supporting intensity height, but ductility is very little, and deformability is poor; For the underground Soft Rock Mine of superficial part (colliery less) as buried depth, the normal at present ductility anchor pole (as pipe-seam type anchor rod and hydraulic expansion type anchor stock) that adopts, the ductility of this class anchor pole is more much bigger than threaded anchor rod, but their bearing strength is but much lower than threaded anchor rod.
Along with the mining depth of modern mining industry increases gradually, in the deep resource exploitation, because the country rock large deformation that high-ground stress causes, make common threaded anchor rod, pipe-seam type anchor rod and hydraulic expansion type anchor stock on supporting effect, be faced with serious challenge, because threaded anchor rod is the very big anchor pole of a kind of rigidity, the deflection that can provide is very little, under the situation of deep rock mass large deformation, twisted steel anchor rod tends to cause anchor pole indentation rock mass inside because the deflection of itself is not enough and failure damage (being commonly called as " taking off trousers " destroys) takes place.Equally, though ductility anchor poles such as pipe-seam type anchor rod can provide large deformation, can't satisfy the supporting intensity under heavily stressed, often because of the excessive rupture failure that causes of rock mass internal stress.Therefore, on the supporting problem of heavily stressed large deformation soft-rock tunnel at the deep, we propose to design a kind of high strength that both had, has simultaneously the thinking of the novel anchor rod of large deformation ability again, require this anchor pole should have the same advantages of high bearing capacity with the rigid thread anchor pole, simultaneously can also be in its damage inactivation prerequisite for moderate finite deformation ability as pipe-seam type anchor rod.
Summary of the invention
Technical problem to be solved by this invention provides a kind of high strength that both had, the mining compatible deformation energy-absorption anchor rod of suitable heavily stressed large deformation Mining in Rock Mass that has the large deformation ability again simultaneously.
In order to solve the problems of the technologies described above, the mining compatible deformation energy-absorption anchor rod of heavily stressed large deformation Mining in Rock Mass that is suitable for provided by the invention, the body of rod of this anchor pole mainly is made up of the lengthening anchoring section straight-bar body and the crooked body of rod of energy-absorbing section, and be provided with thread segment near the crooked body of rod one end of described energy-absorbing section, on described thread segment, be rotary with clamp nut, be set with pallet being on the described thread segment between the crooked body of rod of described clamp nut and described energy-absorbing section.
On described long anchoring section straight-bar body, be provided with agitator.
Described agitator is located on the described long anchoring section straight-bar body end away from the crooked body of rod of described energy-absorbing section.
The crooked body of rod of described energy-absorbing section is the crooked body of rod of wave energy-absorbing section.
The crooked body of rod of described wave energy-absorbing section is the sinusoidal wave bending section that is processed by heat treated mode by the straight-bar screw-thread steel.
Adopt the mining compatible deformation energy-absorption anchor rod of suitable heavily stressed large deformation Mining in Rock Mass of technique scheme, its mechanism of action is: after installing, by lengthening anchoring section straight-bar body with anchor pole one end firm stick on roadway surrounding rock body deep, the other end is fixed on the surface of roadway surrounding rock body by pallet and clamp nut, and applies certain prestressing force on the body of rod.At this moment, because prestressing force is less, so it is also smaller to produce supporting power.Deep Soft Rock Tunnel is under heavily stressed effect, country rock is to free face extrusion distortion, this moment, country rock increased gradually to the active force of anchor pole, when arriving to a certain degree, the crooked body of rod of the energy-absorbing section of anchor pole begins to stretch elongated, absorption portion rock mass deformation energy, simultaneously anchor pole also applies a reaction force to the country rock body of institute's supporting and limits surrouding rock deformation; Along with the further increase of surrouding rock deformation, to the also increase gradually of active force of the body of rod, the crooked body of rod of energy-absorbing section discharges bigger distortion and absorbs more energy, simultaneously the country rock in the supporting scope is produced bigger reaction force, limits its further distortion; Stretching fully when the crooked body of rod quilt of energy-absorbing section, this moment, the body of rod bore maximum pressure from surrounding rock, and effect is equivalent to a high-intensity rigidity anchor pole.Since the deformation characteristics in high stressed soft rock tunnel be into the lane initial stage press soon, deflection is big, energy-absorption anchor rod not only allowed but also limit its distortion at the surrouding rock deformation initial stage, on room and time, produce compatible deformation with the country rock body, both made its internal pressure be able to appropriateness and discharged (being stored in the crooked body of rod of energy-absorbing section), excessive deformation is again by reasonable limits simultaneously.After surrouding rock deformation was stable, this anchor pole can play the effect of high strength rigidity anchor pole again, and enough supporting power is provided.
Major advantage of the present invention is: (1) is simple in structure, and the screw-thread steel material is easy to get, and realizes extensive batch machining easily; (2) adopt lengthening resin anchoring mode, and designed agitator, strengthened the mixing effect of resin explosive roll, anchored force is big, and anchoring effect is good; (3) the crooked body of rod of the energy-absorbing section of this anchor pole allows deformability big, can realize the synchronous coordination distortion of anchor pole and country rock, reach and allow when pressing effect that the supporting power of this anchor pole can rise again rapidly when being elongated to the design variations amount, become high-strength rigidity anchor pole, the further excessive deformation of control country rock.The characteristics of this anchor pole have determined it can adapt to the extreme supporting condition of the heavily stressed large deformation soft-rock tunnel in deep, for the safety and high efficiency of deep resource is given security.
Description of drawings
Fig. 1 is a structural representation of the present invention,
Fig. 2 is the partial structurtes enlarged drawing of body of rod middle part intercepting among Fig. 1, comprises part straight-bar and part bent stick.
The specific embodiment
The invention will be further described below in conjunction with the drawings and specific embodiments.
Referring to Fig. 1 and Fig. 2, one end of the crooked body of rod 2 of wave energy-absorbing section is provided with lengthening anchoring section straight-bar body 1, the length of lengthening anchoring section straight-bar body 1 is 500～800mm, material is the screw-thread steel of external diameter 22mm, the other end of the crooked body of rod 2 of wave energy-absorbing section is provided with thread segment 5, on thread segment 5, be rotary with clamp nut 4, be set with pallet 3 being on the thread segment 5 between the crooked body of rod 2 of clamp nut 4 and wave energy-absorbing section, the end away from the crooked body of rod 2 of wave energy-absorbing section on lengthening anchoring section straight-bar body 1 is provided with agitator 6.The crooked body of rod 2 of wave energy-absorbing section can be out of shape with the country rock synchronous coordination, the crooked body of rod 2 of wave energy-absorbing section is the sinusoidal wave bending sections that processed by heat treated mode by the straight-bar screw-thread steel, and it is according to designing that the number of parameter such as each sine-shaped length, amplitude and waveform allows maximum deformation quantity by the design of heavily stressed roadway with large deformation; Agitator 6 is the Φ 6mm reinforcement bars that are welded on two long 50mm of lengthening anchoring section straight-bar body 1 tip position, and purpose is to increase stirring action when in big boring this anchor pole being installed, and resin explosive roll is fully stirred, and strengthens the resin anchoring effect.
Processing and fabricating of the present invention:
Referring to Fig. 1 and Fig. 2, material of main part of the present invention is a long straight linear screw-thread steel bar (diameter 22mm), reserve one section 500～800mm straight-bar body as lengthening anchoring section straight-bar body 1 at one end (left side), and bar dowel of each weldering long 50mm, diameter 6mm is the mixing effect of agitator 6 when being used to strengthen resin anchoring in these termination portion both sides.At the long thread segment 5 of the other end (right side) the processing 100mm of the straight linear screw-thread steel bar of length, join resin anchor general clamp nut 4 and pallet 3.On the close straight-bar body on right side, process the crooked body of rod 2 of one section wave energy-absorbing section then by heat treatment mode, naturally cool to room temperature then, as shown in Figure 2, the crooked body of rod 2 of this wave energy-absorbing section is made up of several nearly sinusoidal wavelet units, each wavelet unit is all extending under the effect of rock mass internal stress, absorb the rock mass deformation energy simultaneously, until being straightened fully, its elongation can be controlled (for certain with its deflection of a kind of waveform parameter) by waveform parameter, therefore, the structural strain's amount of compatible deformation energy-absorption anchor rod can be controlled, the foundation of design is that the maximum of different rock mass under the different stress conditions allows deflection, controls by the number that changes wavelet unit on the body of rod during design.
Installation process of the present invention:
Similar with the installation of ordinary resin anchor pole, the compatible deformation energy-absorption anchor rod also is at first to get installation boring (because the compatible deformation energy-absorption anchor rod has the wave bending section with rock bolting jumbo in the roadway surrounding rock body, the distance of crest and trough is greater than body of rod diameter, so required installing hole diameter is also big than the aperture of ordinary resin anchor pole); At the bottom of the length of anchoring has blown to the hole with high-pressure blast with 3～5 resin explosive rolls as required then; The 3rd step, clamp the anchor pole afterbody with chassis, after manually importing anchored end in the installing hole, make the quick precession agitating resin of anchor pole, lengthening anchoring section straight-bar body 1 part of anchor pole is immersed in the anchoring resin fully, and keep the crooked body of rod 2 not anchorings of wave energy-absorbing section, can under the effect of power, freely stretch, after treating that resin solidifies fully, suitably apply prestressing force after installing pallet 3 and clamp nut 4, finish installation.
The embodiment of the invention:
Guizhou Province opens the phosphate fertilizer base that phosphorylcholine group is China's maximum, and the high-grade phosphate rock resource that it has accounts for 45% of national reserves.Road Ping Kuang is as its main body mine, build the ore deposit from last century since, accumulative total is adopted the tens million of tons of yield, for great contribution has been made in the economic construction of country.Along with mine superficial part resource exploitation finishes, to the deep development, the level to 540m has been exploited in this deep, ore deposit at present gradually in back production, and mining depth reaches nearly 800m relatively, belongs to the mine of deep mining.Because the stress of primary rock in mineral deposit increases gradually, deep tunnel ground is pressed and is manifested seriously, the problem of bringing is that the mine is mainly opened up and development heading supporting difficulty, original support technology and measure were lost efficacy, tunnel repair rate height, there are phenomenons such as regular roof fall, sheet nation and pucking after the permanent roadway support, need repeatedly to safeguard and reinforce, increased difficulty and the support cost produced greatly.The main development work in this deep, mine is after having adopted the compatible deformation energy-absorption anchor rod among the present invention to carry out supporting, the whole supporting effect in tunnel obviously improves, the long-term structural strain's amount in tunnel reduces greatly, it only is 1/4～1/3 of original ordinary resin bolt support, improve the supporting safety significantly, reduced the roadway support cost.
Claims (5)
1. one kind is applicable to the mining compatible deformation energy-absorption anchor rod of heavily stressed large deformation Mining in Rock Mass, it is characterized in that: the body of rod mainly is made up of the lengthening anchoring section straight-bar body (1) and the crooked body of rod of energy-absorbing section (2), and be provided with thread segment (5) near the crooked body of rod one end of described energy-absorbing section, on described thread segment (5), be rotary with clamp nut (4), be set with pallet (3) being on the described thread segment (5) between the crooked body of rod of described clamp nut (4) and described energy-absorbing section.
2. the mining compatible deformation energy-absorption anchor rod of heavily stressed large deformation Mining in Rock Mass that is suitable for according to claim 1 is characterized in that: be provided with agitator (6) on described long anchoring section straight-bar body (1).
3. the mining compatible deformation energy-absorption anchor rod of heavily stressed large deformation Mining in Rock Mass that is suitable for according to claim 2 is characterized in that: described agitator (6) is located at the last end away from the crooked body of rod of described energy-absorbing section of described long anchoring section straight-bar body (1).
4. according to claim 1, the 2 or 3 described mining compatible deformation energy-absorption anchor rods of heavily stressed large deformation Mining in Rock Mass that are suitable for, it is characterized in that: the crooked body of rod of described energy-absorbing section is the crooked body of rod (2) of wave energy-absorbing section.
5. the mining compatible deformation energy-absorption anchor rod of heavily stressed large deformation Mining in Rock Mass that is suitable for according to claim 4, it is characterized in that: the crooked body of rod of described wave energy-absorbing section (2) is the sinusoidal wave bending section that is processed by heat treated mode by the straight-bar screw-thread steel.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010254537 CN101929347A (en) | 2010-08-17 | 2010-08-17 | Coordinated-deformation energy-absorption anchor rod suitable for mining high-stress large-deformation rock mass |
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| CN 201010254537 CN101929347A (en) | 2010-08-17 | 2010-08-17 | Coordinated-deformation energy-absorption anchor rod suitable for mining high-stress large-deformation rock mass |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102865088A (en) * | 2012-09-12 | 2013-01-09 | 山东科技大学 | Tension and compression coupling type high-strength and high-deformation anchor rod and method for using same |
| CN103590844A (en) * | 2013-11-13 | 2014-02-19 | 煤炭工业济南设计研究院有限公司 | High pre-stressing force pressure yielding and equalizing coupling anchorage device for soft rock supporting |
| CN103758550A (en) * | 2014-01-06 | 2014-04-30 | 成都理工大学 | Liquid-expansion type yielding anti-seismic high-ground-temperature-resistant anchor bolt |
| CN103821547A (en) * | 2014-03-21 | 2014-05-28 | 洛阳理工学院 | Shockproof large-deformation anchor rod |
| CN105736024A (en) * | 2016-02-02 | 2016-07-06 | 重庆大学 | Self-adaptive energy-absorption anchor rod |
| CN105736023A (en) * | 2016-02-02 | 2016-07-06 | 重庆大学 | Large-deformation energy-absorption anchor rod |
| CN105863696A (en) * | 2016-05-17 | 2016-08-17 | 太原理工大学 | Corrugated anchored rod device high in strength and large in deformation |
| CN106285747A (en) * | 2016-09-27 | 2017-01-04 | 中国恩菲工程技术有限公司 | Anchor rod component and the anchor with it |
| CN106640161A (en) * | 2016-11-15 | 2017-05-10 | 北京科技大学 | High-strength energy-absorbing anchor rod with good extensive quantity |
| CN107893673A (en) * | 2017-11-01 | 2018-04-10 | 中国科学院武汉岩土力学研究所 | A kind of anti-rock burst and the large deformation wing formula extrusion pressing type energy-absorption anchor rod |
| CN107939427A (en) * | 2017-12-21 | 2018-04-20 | 北京科技大学 | A kind of energy-absorbing anti-seismic anchor rod |
| CN111764934A (en) * | 2020-07-08 | 2020-10-13 | 上海应用技术大学 | Advanced grouting support method for advanced support small guide pipe and deep soft rock roadway |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102865088B (en) * | 2012-09-12 | 2015-04-08 | 山东科技大学 | Tension and compression coupling type high-strength and high-deformation anchor rod and method for using same |
| CN102865088A (en) * | 2012-09-12 | 2013-01-09 | 山东科技大学 | Tension and compression coupling type high-strength and high-deformation anchor rod and method for using same |
| CN103590844A (en) * | 2013-11-13 | 2014-02-19 | 煤炭工业济南设计研究院有限公司 | High pre-stressing force pressure yielding and equalizing coupling anchorage device for soft rock supporting |
| CN103758550A (en) * | 2014-01-06 | 2014-04-30 | 成都理工大学 | Liquid-expansion type yielding anti-seismic high-ground-temperature-resistant anchor bolt |
| CN103821547B (en) * | 2014-03-21 | 2016-08-24 | 洛阳理工学院 | A kind of shock resistance large deformation anchor rod |
| CN103821547A (en) * | 2014-03-21 | 2014-05-28 | 洛阳理工学院 | Shockproof large-deformation anchor rod |
| CN105736024A (en) * | 2016-02-02 | 2016-07-06 | 重庆大学 | Self-adaptive energy-absorption anchor rod |
| CN105736023A (en) * | 2016-02-02 | 2016-07-06 | 重庆大学 | Large-deformation energy-absorption anchor rod |
| CN105863696A (en) * | 2016-05-17 | 2016-08-17 | 太原理工大学 | Corrugated anchored rod device high in strength and large in deformation |
| CN106285747A (en) * | 2016-09-27 | 2017-01-04 | 中国恩菲工程技术有限公司 | Anchor rod component and the anchor with it |
| CN106640161A (en) * | 2016-11-15 | 2017-05-10 | 北京科技大学 | High-strength energy-absorbing anchor rod with good extensive quantity |
| CN107893673A (en) * | 2017-11-01 | 2018-04-10 | 中国科学院武汉岩土力学研究所 | A kind of anti-rock burst and the large deformation wing formula extrusion pressing type energy-absorption anchor rod |
| CN107939427A (en) * | 2017-12-21 | 2018-04-20 | 北京科技大学 | A kind of energy-absorbing anti-seismic anchor rod |
| CN107939427B (en) * | 2017-12-21 | 2023-09-26 | 北京科技大学 | Energy-absorbing-anti-seismic anchor rod |
| CN111764934A (en) * | 2020-07-08 | 2020-10-13 | 上海应用技术大学 | Advanced grouting support method for advanced support small guide pipe and deep soft rock roadway |
| CN111764934B (en) * | 2020-07-08 | 2022-07-05 | 上海应用技术大学 | Advanced grouting support method for advanced support small guide pipe and deep soft rock roadway |
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Application publication date: 20101229 |