CN202882942U - Confined concrete quantifying yielding arch centering based on mining U-shaped steels - Google Patents

Confined concrete quantifying yielding arch centering based on mining U-shaped steels Download PDF

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Publication number
CN202882942U
CN202882942U CN 201220535149 CN201220535149U CN202882942U CN 202882942 U CN202882942 U CN 202882942U CN 201220535149 CN201220535149 CN 201220535149 CN 201220535149 U CN201220535149 U CN 201220535149U CN 202882942 U CN202882942 U CN 202882942U
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arch
mine
shaped steel
confined concrete
quantitatively
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CN 201220535149
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Chinese (zh)
Inventor
李为腾
李术才
王�琦
王富奇
阮国强
左金忠
张波
王洪涛
王德超
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Shandong University
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Shandong University
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Abstract

The utility model relates to a confined concrete quantifying yielding arch centering based on mining U-shaped steels. The confined concrete quantifying yielding arch centering is in an arch-shaped solid structure and is formed by a plurality of arch-shaped single frames in a longitudinally connecting mode. Each arch-shaped single frame is in an arch-shaped structure and is formed by a plurality of tubular composite components in an encircling mode. A quantifying yielding ring is arranged at the joints between every two tubular composite components. The two tubular composite components are mutually connected through a sleeve which is sleeved outside the quantifying yielding ring and end sockets of the two tubular composite components. A stop clamp is arranged below each sleeve and is used for preventing the sleeve from moving downwards. The confined concrete quantifying yielding arch centering based on the mining U-shaped steels is simple in structure, convenient to connect, strong in retaining and protecting capacity, large in the surface protecting area, capable of yielding in a quantification mode, good in stability and reasonable in stress, and is used for retaining and protecting of deep or soft rock roadways, tunnels and chambers hard to retain and protect.

Description

Quantitatively allow the pressure bow member based on the confined concrete of mine U-shaped steel
Technical field
The utility model relates to a kind of suspension device, and the confined concrete that relates in particular to the underground constructions such as a kind of difficult supporting chamber for complex conditions such as deep or soft rocks, tunnel, tunnel quantitatively allows the pressure bow member.
Background technology
Chinese scholars is by researching and proposing and having developed various support forms, such as bolt-spary supports, the spray of anchor rete cord, metallic support, high strength arc plate etc.Along with socioeconomic development, further to dark, wide future development, the casing position is more and more darker for underground rock engineering, and engineering geological conditions becomes increasingly complex.The factors such as the geological structures such as high-ground stress, Soft Rock Rheology, tomography, underground water cause underground construction to face unprecedented supporting difficulty.Existing support technology can not well satisfy the surrounding rock supporting requirement of on-the-spot complex condition, the especially more difficult supporting of satisfying km Deep Soft Rock tunnel.
Present stage the deep high stress and soft rock mine roadway and the support form commonly used of chamber group be U-shaped steel bracket.But there is following problem in U-shaped steel bracket when surrounding rock supporting: 1. supporting intensity is not enough, this problem is not obvious in the superficial part surrounding rock supporting, but the deep tunnel in present domestic mining area, a plurality of deep such as the areas such as Huainan, Juye, the phenomenon of U-shaped steel bracket surrender, fracture has all appearred in the U36 steel bracket that adopts, and higher at the compression damage proportion of spandrel and arch crown part; 2. support cost is high, and every meter steel weight of mining U36 steel is 35.87kg/m, and steel using amount is large, and support cost is relatively high; 3. working resistance is low, when U-shaped steel bracket was worked in its strength range, its working resistance was only relevant with Support joint place frictional resistance, and frictional resistance depends on the locking degree of card cable, China's U-shaped steel bracket ubiquity coupling mechanism force is not enough, the phenomenon that working resistance of support is relatively low.4. can not quantitatively allow pressure, adopt the card cable as the node type of attachment, can carry out certain pressures that allow, but it allows pressure amount and allow pressure be difficult to hold and control opportunity.
In recent years, a kind of steel pipe concrete bracket for roadway support occurred, this support has higher supporting intensity, can be comparatively effective supported laneway, for Deep Soft Rock Tunnel provides a kind of novel support pattern.But this support remains in some problems, as: 1. protect the little and stress of surface area and concentrate, the steel pipe concrete bracket of circular cross-section is that line contacts with the country rock surface in theory, and contact area is little, on the one hand to the country rock surface produce to protect surface area little, easily cause on the other hand the stress of steel tube surface to concentrate; 2. can't quantitatively allow pressure, it is necessary that the allowing of deep large deformation surrounding rock supporting pressed, existing steel pipe concrete bracket can't realize allowing the pressure amount and allow pressure opportunity controlled allow the pressure effect; 3. bending rigidity is not enough, and the deep tunnel country rock is subjected to the phenomenon of bias voltage obvious, and arch support proposes higher requirement to its bending rigidity under bias effect.
On the whole, for the underground constructions such as day by day complicated deep or soft-rock tunnel, tunnel, chamber, still there is certain problem in existing support pattern, can not satisfy the growing supporting needs of difficulty, has affected production and the safety of deep rock mass engineering project.
Summary of the invention
There are some problems in the mine U-shaped steel bracket, but be the product through development in science and technology decades after all, under several generations' research is made great efforts, the section form of mine U-shaped steel bracket and size are day by day scientific and reasonable, its technique and technology of producing, process, install, using is all very ripe, be a complete production and application chain, have very strong development potentiality.The purpose of this utility model is the situation of the pluses and minuses coexistence of the problem that exists for the mine U-shaped steel bracket and industrial advantage thereof, by research, learn from other's strong points to offset one's weaknesses, utility model quantitatively allow the pressure bow member based on the confined concrete of mine U-shaped steel.The utility model the purpose of this utility model is achieved through the following technical solutions:
Quantitatively allow the pressure bow member based on the confined concrete of mine U-shaped steel, it is the arch stereochemical structure that is formed by connecting by vertical splicing sleeve by the single frame of a plurality of arches, the arcuation structure of the single frame of arch for being surrounded by the more piece tubular composite member, the junction of 2-section pipe shape composite component is provided with and quantitatively allows pressure ring, 2-section pipe shape composite component quantitatively allows the sleeve pipe of pressure ring and 2-section pipe shape composite component termination outside interconnect by being enclosed within, and is provided with the block card that stops sleeve pipe to move downward below the sleeve pipe.
Described tubular composite member forms by sealing steel pipe and being filled in the concrete that seals steel duct, and its shape is determined according to the global shape of bow member, is generally arc.The sealing steel pipe is for being formed by mine U-shaped steel and sealing Plate Welding, and the sealing steel plate is in outside contact surface, and its cross section of sealing steel pipe is arch or isosceles trapezoid.
Described sealing steel duct is provided with deep floor or stiffener, strengthens the bending resistance of bow member.
Have grout hole and steam vent on the described sealing steel pipe sidepiece tube wall.
Above-mentioned arch stereochemical structure is stalk arch, stalk three-core arch form or the shape of a hoof.
The arch springing place of the single frame of described arch realizes end arch and the connection of being connected arch by adpting flange.
Tubular composite member is 3 ~ 6 joints, according to on-the-spot actual needs, designs joint number and the shape of different hollow steel pipes.
Can be found out by the technical scheme that above-mentioned the utility model provides, described confined concrete based on the mine U-shaped steel quantitatively allows the pressure bow member, have following remarkable advantage: 1. supporting intensity is high, economical rationality, itself just has higher supporting intensity the mine U-shaped steel, the restriction concrete member that consists of has steel and concrete advantage concurrently, bi-material shows " symbiosis " during pressurized in mechanical property, guarantee that material property is not fully exerted, because the concrete material cost is lower, make the bow member macroeconomic higher simultaneously; 2. bending rigidity is large, is provided with stiffener (deep floor) in the sealing steel duct, and the bending resistance of bow member is got a promotion, and can successfully manage the country rock bias effect; 3. can quantitatively allow pressure, quantitatively allow and press node to make bow member be subject to the confined pressure effect to reach when setting limit, can allow pressure, and allow the pressure amount can manual control; 4. it is large to protect surface area, proximal line contact action between relative mine U-shaped steel arch frame and circular steel tube concrete support and the country rock, country rock is had the larger surface area that protects, be conducive to Support Resistance wider to the country rock internal delivery, can effectively improve the surrouding rock stress distribution; 5. the support stress concentration degree is low, and support contacts with the country rock face, and it is stressed concentrated to have reduced the bow member external surface, has reduced because of the concentrated disrumpent feelings situation of spandrel that causes of external surface stress; 6. possess mine U-shaped steel advantage, can directly utilize the techniques such as the existing production of mine U-shaped steel arch frame, processing, installation, use, corresponding equipment does not need to change, and only increases on its basis several roads simple procedures newly and gets final product.
Should quantitatively allow based on the confined concrete of mine U-shaped steel and press bow member to be applicable to the supporting of all difficulties tunnel, tunnel, chamber etc., be particularly useful for the supporting of the roadway with large deformation such as deep or soft rock.
The utility model is simple in structure, the device is easy to connect, support capacity is strong, protect surface area large, can quantitatively allow pressure, good stability, reasonable stress, can quantitatively allow pressures, be used for the supporting of deep or soft rock difficulty supported laneway, tunnel, chamber.
Description of drawings
Fig. 1 is that the utility model is based on the structural representation of the confined concrete bow member of mine U-shaped steel;
Fig. 2 is the A-A sectional drawing among Fig. 1, is the schematic diagram of the cross section of the single frame of arch;
Fig. 3 is the B place enlarged drawing among Fig. 1, presses the schematic diagram of node for quantitatively allowing;
Fig. 4 is the B-B sectional drawing among Fig. 1, presses the schematic diagram of node cross section for quantitatively allowing;
Fig. 5 is the C place enlarged drawing among Fig. 1, is the schematic diagram of arch springing connected node;
Fig. 6 is the C-C sectional drawing among Fig. 1, is the schematic diagram of the cross section of arch springing connected node.
Marginal data: 1-tubular composite member; 2-quantitatively allow the pressure node; 3-arch springing connected node; 4-end arch grout hole; 5-crown grout hole; 6-vertically splicing sleeves; 7-sealing steel pipe; 8-sealing steel plate; 9-concrete; 10-stiffener (deep floor); 11-sleeve pipe; 12-quantitatively allow pressure ring; 13-block card; 14-crown steam vent; 15-side arch steam vent; 16-side arch adpting flange; 17-end arch adpting flange; 18-high-strength bolt; 19-grouting through hole.
The specific embodiment
Below in conjunction with accompanying drawing and the specific embodiment the utility model is described further.
Quantitatively allow the pressure bow member based on the confined concrete of mine U-shaped steel, it is the arch stereochemical structure that is formed by connecting by vertical splicing sleeve 6 by the single frame of a plurality of arches, the arcuation structure of the single frame of arch for being surrounded by more piece tubular composite member 1, the junction of 2-section pipe shape composite component 1 is provided with and quantitatively allows pressure ring 12,2-section pipe shape composite component 1 quantitatively allows the sleeve pipe 11 of pressure ring 12 and 2-section pipe shape composite component 1 termination outside interconnect by being enclosed within, and is provided with the block card 13 that stops sleeve pipe 11 to move downward below the sleeve pipe 11.
Tubular composite member 1 forms by sealing steel pipe 7 and being filled in the concrete 9 that seals steel pipe 7 inside, and its shape is determined according to the global shape of bow member, is generally arc.Sealing steel pipe 7 is for being welded by mine U-shaped steel and sealing steel plate 8, and sealing steel plate 8 is in outside contact surface, and sealing steel pipe 7 its cross sections are arch or isosceles trapezoid.
As shown in Figure 1, first described more piece sealing steel pipe 7 is interconnected to form the bow member form, quantitatively allows and press node 2 temporarily not install.Then pour into fill concrete 9 by end arch grout hole 4 and crown grout hole 5 in sealing steel pipe 7 respectively, crown steam vent 14 and side arch steam vent 15 are positioned at quantitatively to allow presses node 2 places (Fig. 2), bow member bilateral symmetry layout.Be provided with vertical splicing sleeve 6 on the bow member, be used for fixedly vertical connecting rod of bow member, prevent that bow member from toppling over, described vertical splicing sleeve 6 processes for round steel pipe.
As depicted in figs. 1 and 2, described tubular composite member 1 is made of sealing steel pipe 7 and concrete 9, sealing steel pipe 7 is welded by mine U-shaped steel and sealing steel plate 8, in order to increase the bow member bending resistance, can set up stiffener (deep floor) 10 in sealing steel pipe 7 inside.Sealing steel pipe 7 makes the mine U-shaped steel become the steel pipe of closed cross-section, and one side has increased the bending resistance of bow member, has obviously increased on the other hand the surface area that protects of bow member.Described mine U-shaped steel and sealing steel plate 8 all have Multiple Type, and described concrete 9 also can be selected dissimilar and proportioning as required.
Such as Fig. 1, Fig. 3 and shown in Figure 4, described quantitatively allowing presses node 2 to be used for connecting the described tubular composite member 1 of more piece, quantitatively allow and press node by sleeve pipe 11, quantitatively allow pressure ring 12, block card 13 form, after filling concrete is finished, to quantitatively allow pressure ring 12 be installed in desired location, till then down sliding sleeve pipe 11 to block card 13 stops.Described quantitatively allowing presses node 2 can be arranged on as required the different parts of bow member.The sectional dimension of sleeve pipe 11 is slightly larger than the sectional dimension of tubular composite member 1, and described tubular composite member 1 just can be inserted in the sleeve pipe 11.
Reach when setting limit when bow member is stressed, quantitatively allow pressure ring 12 can realize by the compressive strain of self pressures that allow of bow member, the described pressure ring 12 that quantitatively allows has Multiple Type, can allow pressure point select according to the difference of bow member setting.
Such as Fig. 1, Fig. 5 and shown in Figure 6, the end arch of described bow member connects by arch springing connected node 3 with being connected to encircle, arch springing connected node 3 comprises side arch adpting flange 16, end arch adpting flange 17 and high-strength bolt 18, high-strength bolt 18 connects up and down two flanges, have grouting through hole 19 in the middle part of two flanges, be convenient to concrete 9 and flow.
Restriction concrete member based on the mine U-shaped steel of the present utility model is a kind of novel supporting and protection structure.It by mine U-shaped steel and the sealing steel pipe 7 that forms of sealing steel plate 8 as shell, interior filling concrete 9 compositions.Described tubular composite member 1 utilizes sealing steel pipe 7 and the interaction of concrete 9 in loading process that concrete 9 is under the three-dimensional compression chord state, thereby the intensity of concrete 9 is improved, and plasticity and toughness properties are greatly improved.Because the effect of concrete 9 can be avoided or delay to seal steel pipe 7 cripling occurs, bi-material shows " symbiosis " during pressurized in mechanical property, thereby guarantees giving full play to of material property simultaneously.
Described confined concrete bow member generally is comprised of 4 pipe joint shape composite components 1, is easy to carry to the job site.If when not needing the end to encircle, can adopt the form of top side 3 pipe joint shape composite components 1.At first at the scene that the Concrete-Filled Square Steel Tube bracket assembled is good, and then concrete 9 injected in the sealing steel pipe 7 by grout hole, so that the Concrete-Filled Square Steel Tube support is convenient to transportation, is moved, support process is simple, practical.
Confined concrete quantitatively allows presses bow member to be provided with stiffener 10 in sealing steel pipe 7 inside, and the bending resistance of bow member is got a promotion, and can successfully manage the country rock bias effect, and bending rigidity is large.
Described confined concrete quantitatively allows presses proximal line contact action between bow member relative mine U-shaped steel arch frame and circular steel tube concrete support and the country rock, owing to be that sealing steel plate 8 contacts with country rock, on the one hand country rock had the larger surface area that protects, be conducive to Support Resistance wider to the country rock internal delivery, can effectively improve the surrouding rock stress distribution; Support contacts with the country rock face on the other hand, and the support stress concentration degree is low, and it is stressed concentrated to have reduced the bow member external surface, has reduced because of the concentrated disrumpent feelings situation of spandrel that causes of external surface stress.
Described confined concrete bow member is utility model on the basis of mine U-shaped steel, possess mine U-shaped steel advantage, can directly utilize the techniques such as the existing production of mine U-shaped steel arch frame, processing, installation, use, corresponding equipment does not need to change, and only newly-increased several procedures get final product on its basis.
The above; it only is the better specific embodiment of the utility model; but protection domain of the present utility model is not limited to this; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; the variation that can expect easily or replacement all should be encompassed within the protection domain of the present utility model.

Claims (7)

1. quantitatively allow the pressure bow member based on the confined concrete of mine U-shaped steel, it is characterized in that, it is the arch stereochemical structure that is formed by connecting by vertical splicing sleeve by the single frame of a plurality of arches, the arcuation structure of the single frame of arch for being surrounded by the more piece tubular composite member, the junction of 2-section pipe shape composite component is provided with and quantitatively allows pressure ring, 2-section pipe shape composite component quantitatively allows the sleeve pipe of pressure ring and 2-section pipe shape composite component termination outside interconnect by being enclosed within, and is provided with the block card that stops sleeve pipe to move downward below the sleeve pipe.
2. the confined concrete based on the mine U-shaped steel according to claim 1 quantitatively allows the pressure bow member, it is characterized in that, described tubular composite member forms by sealing steel pipe and being filled in the concrete that seals steel duct, the sealing steel pipe is for being formed by mine U-shaped steel and sealing Plate Welding, the sealing steel plate is in outside contact surface, and its cross section of sealing steel pipe is arch or isosceles trapezoid.
3. the confined concrete based on the mine U-shaped steel according to claim 2 quantitatively allows the pressure bow member, it is characterized in that described sealing steel duct is provided with deep floor or stiffener.
4. the confined concrete based on the mine U-shaped steel according to claim 2 quantitatively allows the pressure bow member, it is characterized in that, has grout hole and steam vent on the described sealing steel pipe sidepiece tube wall.
5. the confined concrete based on the mine U-shaped steel according to claim 1 quantitatively allows the pressure bow member, it is characterized in that described arch stereochemical structure is stalk arch, stalk three-core arch form or the shape of a hoof.
6. the confined concrete based on the mine U-shaped steel according to claim 1 quantitatively allows the pressure bow member, it is characterized in that, the connection that the arch springing place of the single frame of described arch realizes end arch and be connected to encircle by adpting flange.
7. the confined concrete based on the mine U-shaped steel according to claim 1 quantitatively allows the pressure bow member, it is characterized in that, described tubular composite member is 3 ~ 6 joints.
CN 201220535149 2012-10-18 2012-10-18 Confined concrete quantifying yielding arch centering based on mining U-shaped steels Expired - Fee Related CN202882942U (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102877862A (en) * 2012-10-18 2013-01-16 山东大学 Confined concrete quantitative yielding lagging jack based on mine U-shaped steel
CN103277116A (en) * 2013-05-31 2013-09-04 山东科技大学 Method for treating floor heaving of soft rock roadway by optimized rubble reinforced concrete arch structure
CN104343458A (en) * 2014-09-29 2015-02-11 湖南科技大学 Full-section wide-width one-piece type steel bracket and supporting method thereof
CN105353111A (en) * 2015-12-16 2016-02-24 山东科技大学 Concrete filled steel tube lagging jack grouting analog system and effect evaluation method
CN107630708A (en) * 2017-11-06 2018-01-26 山东建筑大学 A kind of prefabricated assembled composite support system based on shaped steel
CN108397216A (en) * 2018-05-14 2018-08-14 山东建筑大学 A kind of concrete filled steel tube arch can contracting formula connector and arch

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102877862A (en) * 2012-10-18 2013-01-16 山东大学 Confined concrete quantitative yielding lagging jack based on mine U-shaped steel
CN103277116A (en) * 2013-05-31 2013-09-04 山东科技大学 Method for treating floor heaving of soft rock roadway by optimized rubble reinforced concrete arch structure
CN103277116B (en) * 2013-05-31 2015-07-15 山东科技大学 Method for treating floor heaving of soft rock roadway by optimized rubble reinforced concrete arch structure
CN104343458A (en) * 2014-09-29 2015-02-11 湖南科技大学 Full-section wide-width one-piece type steel bracket and supporting method thereof
CN104343458B (en) * 2014-09-29 2017-05-17 湖南科技大学 Full-section wide-width one-piece type steel bracket and supporting method thereof
CN105353111A (en) * 2015-12-16 2016-02-24 山东科技大学 Concrete filled steel tube lagging jack grouting analog system and effect evaluation method
CN105353111B (en) * 2015-12-16 2016-08-17 山东科技大学 A kind of concrete filled steel tube bow member perfusion analog systems and effect assessment method
CN107630708A (en) * 2017-11-06 2018-01-26 山东建筑大学 A kind of prefabricated assembled composite support system based on shaped steel
CN108397216A (en) * 2018-05-14 2018-08-14 山东建筑大学 A kind of concrete filled steel tube arch can contracting formula connector and arch
CN108397216B (en) * 2018-05-14 2023-11-17 山东建筑大学 Retractable joint of steel tube concrete arch frame and arch frame

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Granted publication date: 20130417

Termination date: 20191018