CN214944361U

CN214944361U - Supporting construction of soft rock tunnel

Info

Publication number: CN214944361U
Application number: CN202121119108.4U
Authority: CN
Inventors: 田海波; 张衡; 孙林元; 李亮雄; 黄攀; 陈源源
Original assignee: Gansu Wansheng Mining Co ltd
Current assignee: Gansu Wansheng Mining Co ltd
Priority date: 2021-05-24
Filing date: 2021-05-24
Publication date: 2021-11-30
Anticipated expiration: 2031-05-24

Abstract

The utility model discloses a supporting structure of a soft rock roadway, which comprises a long anchor cable (1), a short anchor cable (2), a steel bar ladder (3), a metal mesh sheet (4), a steel anchor rod (5), a top plate (6), a metal mesh (7) and a tray (8); the tail ends of the long anchor cable (1) and the short anchor cable (2) are respectively provided with a tray (8); the top plate (6) is arranged at the top end of the roadway; the metal mesh (7) covers the top plate (6) of the roadway; the steel anchor rods (5) fixed on the two sides of the roadway are connected with the metal meshes (4) through steel bar ladders (3) and are arranged on the two sides of the roadway. The utility model discloses changed tunnel section form and supporting construction, the tunnel section adopts the circular arc to encircle the section to through improving prestressing force, change traditional stock into short anchor rope, prestressing force improves to 180KN, simultaneously, increase and protect in table component (W steel band) spreads the surrounding rock with prestressing force, improve the surrounding rock wholeness, reach and maintain the stable purpose of tunnel surrounding rock, make tunnel surrounding rock warp and obtain effective control.

Description

Supporting construction of soft rock tunnel

Technical Field

The utility model relates to a tunnel construction technical field especially relates to supporting construction in soft rock tunnel.

Background

Along with the expansion of the coal mining range, the mining depth is continuously increased, the mining condition is more and more difficult, and particularly, the superposition pressure brought to roadway support by the self expansion of soft rock coal under large burial depth, complex structure and mining stress is always a difficult problem troubling the coal mine roadway support. Because these pressures have time to vary in speed, magnitude and direction, they are non-equal, non-uniform combinations of superimposed pressures. The roadway support can be repeatedly damaged under the action of the uneven superposition pressure, and the stability of the roadway is difficult to ensure by the conventional support technology. The roadway support is unstable, the safety production during the mine construction period is influenced, and potential safety hazards are brought to the later normal use.

Under the existing roadway support conditions, the deformation and damage of the roadway surrounding rock generally have the following characteristics: (1) the roadway has large deformation, and has no stable period under the support of an I-shaped steel shed, thereby showing the obvious soft rock roadway characteristic. (2) The tunnel first begins to deform from the floor, with a bottom bulge, which in turn causes the foot of the slope to become unstable, and finally causes the roof to sink. (3) The roadway is deformed asymmetrically, and the characteristics of mutual dislocation deformation of bottom plate uplift and top plate depression are presented. (4) The top beam of the shed frame has no obvious bending phenomenon, and shed legs have serious bending, twisting and bottom drilling phenomena. (5) The roadway of partial sections is influenced by water, and the surrounding rock is subjected to the phenomenon of argillization and expansion, so that the deformation of the roadway is aggravated.

Many times, the stoping roadway can deform and be seriously damaged in the tunneling process, the moving distance of a top plate and a bottom plate of a partial area is close to about 1m, the coal rock bodies on two sides are loosened and broken, the roadway is usually maintained for many times to maintain the basic stability of the roadway reluctantly, the maintenance investment cost is high, the roadway is influenced by more mining after serving a subsequent coal face, the stability maintenance of the roadway is more difficult, and the normal production is seriously influenced, so that the problem of stoping roadway support is very necessary to be solved, the stoping roadway is used for keeping stability, and more subsequent mining services are provided.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome prior art's not enough, provide the supporting construction in soft rock tunnel.

The purpose of the utility model is realized through the following technical scheme:

the supporting structure of the soft rock roadway comprises long anchor cables, short anchor cables, a steel bar ladder, a metal mesh sheet, a steel anchor rod, a top plate, a metal mesh and a tray; the tail ends of the long anchor cable and the short anchor cable are respectively provided with a tray; the top plate is arranged at the top end of the roadway; the metal net covers the top plate of the roadway; the steel anchor rods fixed on the two sides of the roadway are connected through a steel bar ladder; the metal meshes are arranged at the two sides of the roadway.

The number of the long anchor cables is not less than three rows, the long anchor cables are manufactured by processing 1 multiplied by 7 strands of low-relaxation prestress steel strands with the diameter phi of 21.6 multiplied by 7300mm, the row spacing between the long anchor cables is 1600 multiplied by 1600mm, the long anchor cables are anchored by 4 sections of anchoring agents with the model number of MSK2350, and the pretightening force of the long anchor cables is not less than 230 KN.

The number of the short anchor cables is not less than six rows, the short anchor cables are processed and manufactured by 1 multiplied by 7 strands of low-relaxation prestress steel strands with the diameter phi of 21.6 multiplied by 3600mm, the row spacing between the long anchor cables is 1000 multiplied by 800mm, 2 sections of anchoring agents with the model number of MSK2350 are adopted for anchoring, and the pretightening force of the short anchor cables is not less than 150 KN.

W-shaped steel belts are arranged at the lower parts of the metal nets in an arched mode, trays are arranged at the tail ends of the long anchor cables and the short anchor cables, the trays press the W-shaped steel belts, and the metal nets are fixed.

The tray adopts 300X 16mmQ235 arched steel plates, and the supporting mode is a point anchor.

The supporting structure of the soft rock roadway further comprises an anchor rod tray, the anchor rod tray is installed at the tail end of the steel anchor rod, a 300 x 16mmQ235 arched steel plate is adopted, the pre-tightening torque is not less than 260 N.m, and a 1010 nylon anti-friction gasket is additionally arranged between the anchor rod tray and the nut.

The reinforcing bar ladder adopts phi 12 mm's round steel processing to make, reinforcing bar ladder length is 2200mm, has three hole interval to be 800 mm's hole, and the eyelet size is 80 mm.

The utility model has the advantages that: through the on-site survey roof surrounding rock loose circle, master the development condition of tunnelling surrounding rock roof crack, the utility model discloses changed tunnel section form and supporting construction, because arc type bearing capacity is strong, the tunnel section adopts the arc to encircle the section to through improving prestressing force, change traditional stock into short anchor rope, prestressing force improves to 180KN, simultaneously, increase and protect in the table component (W steel band) spreads the prestressing force to the surrounding rock, improve the surrounding rock wholeness, reach and maintain the stable purpose of tunnel surrounding rock, make tunnel surrounding rock warp and obtain effective control.

Drawings

FIG. 1 is a view showing the structure of the apparatus of the present invention;

in the drawings: 1-long anchor cable, 2-short anchor cable, 3-steel bar ladder, 4-metal mesh sheet, 5-steel anchor rod, 6-top plate, 7-metal mesh and 8-tray.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings.

In this embodiment, as shown in fig. 1, the supporting structure of the soft rock roadway includes a long anchor cable 1, a short anchor cable 2, a steel bar ladder 3, a metal mesh 4, a steel anchor rod 5, a top plate 6, a metal mesh 7, and a tray 8; the tail ends of the long anchor cable 1 and the short anchor cable 2 are respectively provided with a tray 8; the top plate 6 is arranged at the top end of the roadway; the metal mesh 7 covers the roadway roof 6; the steel anchor rods 5 fixed on the two sides of the roadway are connected through a steel bar ladder 3; the metal meshes 4 are arranged at two sides of the roadway.

The number of the long anchor cables 1 is not less than three rows, the long anchor cables 1 are made of 1 multiplied by 7 strands of low-relaxation prestress steel strands with the diameter phi of 21.6 multiplied by 7300mm, the row spacing among the long anchor cables 1 is 1600 multiplied by 1600mm, the long anchor cables are anchored by 4 sections of anchoring agents with the model number of MSK2350, and the pretightening force of the long anchor cables 1 is not less than 230 KN.

The number of the short anchor cables 2 is not less than six rows, the short anchor cables 2 are made of 1 multiplied by 7 strands of low-relaxation prestress steel strands with the diameter phi of 21.6 multiplied by 3600mm, the row spacing of the long anchor cables 1 is 1000 multiplied by 800mm, 2 sections of anchoring agents with the model number of MSK2350 are adopted for anchoring, and the pretightening force of the short anchor cables 2 is not less than 150 KN.

W-shaped steel belts are arranged below the metal nets 7 in an arched mode, trays 8 are arranged at the tail ends of the long anchor cables 1 and the short anchor cables 2, the trays 8 press the W-shaped steel belts, and the metal nets 7 are fixed.

The tray 8 adopts a 300X 16mmQ235 arched steel plate, and the supporting mode is a point anchor.

The supporting structure of the soft rock roadway further comprises an anchor rod tray, the anchor rod tray is installed at the tail end of the steel anchor rod 5, a 300 x 16mmQ235 arched steel plate is adopted, the pre-tightening torque is not less than 260 N.m, and a 1010 nylon anti-friction gasket is additionally arranged between the anchor rod tray and the nut.

Reinforcing bar ladder 3 adopts phi 12 mm's round steel processing to make, reinforcing bar ladder 3 length is 2200mm, has three hole interval to be 800 mm's hole, and the eyelet size is 80 mm.

The metal net 7 in the top plate 6 is welded by phi 6.5mm steel bars, the specification is 2400 multiplied by 900mm, the mesh specification is 100 multiplied by 100mm, the mesh pieces are lapped by 100mm, 14# iron wires are subjected to double-row dislocation binding, and the binding distance is 200 mm.

The metal net sheets 4 on two sides of the roadway are welded by steel bars with the diameter of 6.5mm, the specification is 2400 multiplied by 900mm, and the specification of meshes is 100 multiplied by 100 mm.

The top and the right side of the roadway are made of concrete with the strength of C20, and the thickness of the guniting is 100 mm.

The utility model discloses an analysis, roof 6 amount of sinking is little, and the rate of sinking is slow, gains good actual effect, and tunnel country rock obtains effective control, reduces back lane maintenance frame canopy engineering volume simultaneously, has practiced thrift the cost, and fundamentally solves three soft coal seams and struts difficult problem, has ensured mine safety in production.

Need carry out the canopy reinforcement after former construction and strut, the utility model discloses an adopt length anchor rope, change tunnel section, the tunnel reduces canopy construction, has reduced workman construction strength, and simultaneously, per meter reduces about 1500 yuan of supporting cost.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above, and it should be understood by those skilled in the art that the present invention is not limited by the above embodiments, but only by the description of the above embodiments and the description, without departing from the spirit and scope of the present invention, the present invention can also have various changes and modifications, and these changes and modifications all fall within the scope of the claimed invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The supporting structure of the soft rock roadway is characterized by comprising long anchor cables (1), short anchor cables (2), a steel bar ladder (3), a metal mesh (4), a steel anchor rod (5), a top plate (6), a metal mesh (7) and a tray (8); the tail ends of the long anchor cable (1) and the short anchor cable (2) are respectively provided with a tray (8); the top plate (6) is arranged at the top end of the roadway; the metal net (7) covers the roadway top plate (6); the steel anchor rods (5) fixed on the two sides of the roadway are connected through a steel bar ladder (3); the metal meshes (4) are arranged at two sides of the roadway.

2. The soft rock roadway support structure according to claim 1, wherein the number of the long anchor cables (1) is not less than three, the long anchor cables (1) are made of 1 x 7 low-relaxation prestressed steel strands with the diameter phi of 21.6 x 7300mm, the row spacing between the long anchor cables (1) is 1600 x 1600mm, the long anchor cables are anchored by 4 sections of MSK2350 anchoring agent, and the pretightening force of the long anchor cables (1) is not less than 230 KN.

3. The soft rock roadway support structure according to claim 1, wherein the number of the short anchor cables (2) is not less than six, the short anchor cables (2) are processed by 1 x 7 strands of low-relaxation prestressed steel strands with the diameter of phi 21.6 x 3600mm, the row spacing between the long anchor cables (1) is 1000 x 800mm, the anchor cables are anchored by 2 sections of MSK2350 anchoring agent, and the pretightening force of the short anchor cables (2) is not less than 150 KN.

4. The supporting structure of the soft rock roadway according to claim 1, wherein the W-shaped steel belt is installed under the metal net (7) in an arch shape, the tail ends of the long anchor cables (1) and the short anchor cables (2) are provided with a tray (8), and the tray (8) presses the W-shaped steel belt and fixes the metal net (7).

5. Support structure in soft rock galleries according to claim 1, characterized in that the pallets (8) are 300 x 16mmQ235 arch steel plates in the form of point anchors.

6. The soft rock roadway support structure of claim 1, further comprising an anchor rod tray, wherein the anchor rod tray is installed at the tail end of the steel anchor rod (5), a 300 x 16mmQ235 arched steel plate is adopted, the pre-tightening torque is not less than 260N-m, and a 1010 nylon anti-friction gasket is added between the anchor rod tray and the nut.

7. The soft rock roadway support structure according to claim 1, wherein the steel bar ladder (3) is made of round steel with the diameter of 12mm, the length of the steel bar ladder (3) is 2200mm, three holes with the hole spacing of 800mm are formed, and the hole size is 80 mm.