Soft rock large-deformation tunnel energy type supporting structure

Abstract

The invention relates to the technical field of tunnel supporting, and particularly discloses a soft rock large deformation tunnel energy type supporting structure which comprises a primary supporting layer and a lining, and a plurality of energy absorption retraction assemblies are arranged between the primary supporting layer and the lining; the multiple energy absorption retraction assemblies are arranged along the upper top face of the lining in a spliced mode. The energy absorption retraction assembly comprises a supporting plate, a base, turning plates and a tension spring damper, the base is installed on the lining, the turning plates are arranged in pairs, one ends of the turning plates are hinged to the base, the other ends of the turning plates make rolling contact with the supporting plate, and the tension spring damper is installed between the two turning plates; when the supporting plate is pressed, the angle between the two turning plates is increased. The supporting structure has better anti-deformation and energy-absorbing effects, and the anti-damage capacity of the supporting structure is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel support, and in particular to an energy-type support structure for a soft rock large deformation tunnel. Background Art

[0002] A soft rock large deformation tunnel refers to a tunnel that, under soft rock geological conditions, has a large deformation of the surrounding rock after excavation due to the special physical and mechanical properties of soft rock. This deformation exceeds the deformation range allowed by general tunnel design. Soft rock usually refers to rocks with a uniaxial compressive strength of less than 30MPa, such as mudstone, shale, etc.

[0003] Tunnel energy support is a new support concept based on the energy principle. It emphasizes the mutual conversion and balance of energy between the support structure and the surrounding rock, and realizes effective support of the tunnel surrounding rock by reasonably absorbing, releasing and regulating energy. Traditional support methods mainly focus on providing static support force to resist surrounding rock deformation, while energy-based support pays more attention to the dynamic process of energy change during the support process. Therefore, when the existing support structure is applied to soft rock formations, due to the large deformation of the surrounding rock, the support structure is prone to irreversible deformation during the support process, and cannot effectively offset the impact energy, resulting in failure of the support structure. Therefore, it is urgent to design a new support structure to solve this problem. Summary of the invention

[0004] The purpose of the present invention is to provide an energy-type support structure for a soft rock large deformation tunnel, which has better anti-deformation and energy absorption effects and improves the anti-destruction ability of the support structure.

[0005] The present invention is achieved through the following technical solutions: an energy-type support structure for a soft rock large deformation tunnel, comprising an initial support layer and a lining, wherein a plurality of energy absorption and retraction components are arranged between the initial support layer and the lining; a plurality of the energy absorption and retraction components are spliced ​​and arranged along the upper top surface of the lining; the energy absorption and retraction components comprise a support plate, a base, a flap and a tension spring damper, wherein the base is mounted on the lining, the flaps are arranged in pairs and one end of the flaps is hinged to the base, the other end of the flaps is in rolling contact with the support plate, and the tension spring damper is mounted between the two flaps; when the support plate is under pressure, the angle between the two flaps becomes larger.

[0006] Furthermore, a plurality of radial limiters are evenly arranged between the initial support layer and the support plate, and the radial limiters are cylindrical tube structures.

[0007] Furthermore, a top arch plate is provided between the initial support layer and the lining, and the top arch plate is in contact with the radial limiter; the top arch plate and the energy absorbing and retracting assembly are alternately arranged in the axial direction of the lining.

[0008] Furthermore, it also includes an anchor rod, one end of which passes through the support plate and the initial supporting layer in sequence; the anchor rod is slidably connected to the support plate.

[0009] Furthermore, a plurality of gas struts corresponding to the anchor rods are installed on the lining surface, and the gas struts include a gas cavity and a piston.

[0010] Furthermore, a connecting rope is connected in series between the plurality of support plates, and both ends of the connecting rope are connected to rollers.

[0011] Furthermore, the roller is installed in a box body, both sides of the box body are provided with openings for connecting ropes, and one end of the roller is connected to a clockwork spring.

[0012] Furthermore, it also includes a guide wheel, which is arranged on the lower side of the initial support layer.

[0013] Furthermore, a roller is provided at one end of the flap away from the base.

[0014] The technical solution of the present invention has at least the following advantages and beneficial effects:

[0015] 1. Dynamic point support is achieved by setting up multiple energy-absorbing and retracting components, which can resist pressure and absorb energy, and reduce the deformation of soft rock layers;

[0016] 2. A connecting rope is set in series with the support plate and the energy storage mechanism. When the impact force disappears, the support plate will rebound and reset under the action of the tension spring damper and the spring. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional schematic diagram of the energy-type support structure for a soft rock large deformation tunnel in the present invention;

[0018] Figure 2 It is a schematic structural diagram of the energy absorbing and retracting component in the present invention;

[0019] Figure 3 It is a side view of the energy-type support structure for a soft rock large deformation tunnel in the present invention;

[0020] Figure 4 It is a schematic diagram of the matching structure of the winding roller and the connecting rope in the present invention.

[0021] Figure numerals: 1-initial support layer, 2-lining, 3-energy absorption and retraction assembly, 31-support plate, 32-base, 33-flap, 34-roller, 35-tension spring damper, 4-radial limiter, 5-anchor rod, 6-gas support, 61-air cavity, 62-piston, 7-top arch plate, 8-connecting rope, 9-roller, 10-box, 11-spring spring, 12-guide wheel. DETAILED DESCRIPTION

[0022] The following is further described in conjunction with specific embodiments. Figure 1-Figure 4 As shown, this embodiment is an energy-type support structure for a soft rock large deformation tunnel, comprising an initial support layer 1 and a lining 2, wherein a plurality of energy-absorbing and retracting components 3 are arranged between the initial support layer 1 and the lining 2; the plurality of energy-absorbing and retracting components 3 are spliced ​​and arranged along the upper top surface of the lining 2; the energy-absorbing and retracting components 3 comprise a support plate 31, a base 32, a flap 33 and a tension spring damper 35, wherein the base 32 is mounted on the lining 2, the flap 33 is arranged in pairs and one end of the flap 33 is hinged to the base 32, the other end of the flap 33 is in rolling contact with the support plate 31, and the tension spring damper 35 is mounted on the two flaps. When the support plate 31 is under pressure, the angle between the two flaps 33 becomes larger; specifically, the initial support layer 1 is processed by shotcrete, which is sprayed on the soft rock layer. When the surrounding rock is relatively stable, support is carried out. Multiple support plates 31 are spliced ​​to form a semicircular arch structure, and a certain gap is left between adjacent support plates 31. When the local soft rock layer deforms and applies pressure to a certain support plate 31, the downward pressure of the support plate 31 will pull the angle between the two flaps 33 to increase and expand, and the tension spring damper 35 can absorb part of the impact capacity, thereby reducing damage to the lining 2.

[0023] like Figure 1 As shown, in this embodiment, a plurality of radial limiters 4 are evenly arranged between the initial support layer 1 and the support plate 31, and the radial limiters 4 are cylindrical tube structures; specifically, there are deformation gaps between the radial limiters 4. When the soft rock layer is deformed and squeezed, the cylindrical tube-shaped limit damper has a certain buffering deformation capacity, and can automatically return to its original state when the impact disappears. The radial limiters 4 are arranged at a long axial distance and have a large range of action.

[0024] like Figure 3 As shown, in this embodiment, a top arch plate 7 is further provided between the initial support layer 1 and the lining 2, and the top arch plate 7 is in contact with the radial limiter 4, thereby forming multiple axial hard point supports, and the radial limiter 4 has a certain downward pressure amplitude space between the gap between the top arch plate 7 and the radial limiter 4; the top arch plate 7 and the energy absorption and retraction component 3 are alternately arranged in the axial direction of the lining 2, thereby realizing an alternating anti-impact layout and effectively reducing tunnel deformation.

[0025] like Figure 1 As shown, this embodiment also includes an anchor rod 5, one end of which passes through the support plate 31 and the initial support layer 1 in sequence; the anchor rod 5 is slidably connected to the support plate 31; specifically, the anchor rod 5 is driven into the soft rock layer to strengthen its integrity, and when the local soft rock layer is deformed, the anchor rod 5 is displaced synchronously, and the anchor rod 5 will slide back and forth relative to the support plate 31, or press against the lining 2.

[0026] In order to further improve the impact resistance of the tunnel, a plurality of gas support devices 6 corresponding to the anchor rods 5 are installed on the surface of the lining 2. The gas support device 6 includes an air cavity and a piston. Specifically, when the anchor rods 5 press against the piston of the gas support device 6, the piston will press down and squeeze the air in the air cavity to achieve elastic support and avoid hard contact to damage the lining 2.

[0027] Reference Figure 1 and Figure 3 As shown, in this embodiment, a connecting rope 8 is connected in series between the multiple support plates 31. When the local soft mud layer deforms and presses down the support plate 31, the support plate 31 will move down close to the lining 2, while pulling the connecting rope 8, and rollers 9 are connected to both ends of the connecting rope 8; specifically, the roller 9 has a certain tightening force, and the rotation of the roller 9 will shorten the length of the connecting rope 8, so that the support plate 31 will be reset.

[0028] like Figure 4 As shown, the roller 9 in this embodiment is installed in a box body 10, and openings for the connection rope 8 to be connected are provided on both sides of the box body 10, and one end of the roller 9 is connected to a clockwork spring 11; specifically, the clockwork spring 11 serves as an energy storage device, and when the support plate 31 is compressed, the connection rope 8 becomes longer, and the roller 9 will reverse; when the impact force disappears, the clockwork spring 11 will prompt the roller 9 to rotate forward and rewind around the connection rope 8.

[0029] like Figure 2 As shown, this embodiment also includes a guide wheel 12, which is arranged on the lower side of the initial support layer 1; specifically, the connecting rope 8 forms a ring, and the guide wheel 12 is used to change the pulling direction of the connecting rope 8, and the guide wheel 12 is installed below the support plate 31 fixed at the bottom.

[0030] like Figure 2 As shown, in order to further reduce the friction between the support plate 31 and the flap 33 during the unfolding process when the support plate 31 is impact-resistant, a roller 34 is provided at the end of the flap 33 away from the base 32, and the roller 34 adheres to the surface of the support plate 31 to roll and unfold and retract to its original position.

[0031] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An energy-type support structure for a soft rock large deformation tunnel, characterized by: It comprises an initial support layer (1) and a lining (2), wherein a plurality of energy absorbing and retracting components (3) are arranged between the initial support layer (1) and the lining (2); A plurality of the energy absorbing and retracting components (3) are spliced ​​and arranged along the upper top surface of the lining (2); The energy absorption and retraction assembly (3) comprises a support plate (31), a base (32), a flap (33) and a tension spring damper (35); the base (32) is mounted on the lining (2); the flaps (33) are arranged in pairs and one end of each flap is hinged to the base (32); the other end of each flap (33) is in rolling contact with the support plate (31); and the tension spring damper (35) is mounted between the two flaps (33); When the support plate (31) is compressed, the angle between the two flaps (33) increases.

2. The energy-type support structure for soft rock large deformation tunnel according to claim 1 is characterized by: A plurality of radial limiters (4) are evenly arranged between the initial support layer (1) and the support plate (31), and the radial limiters (4) are cylindrical tube structures.

3. The energy-type support structure for soft rock large deformation tunnel according to claim 2 is characterized by: A top arch plate (7) is also provided between the initial support layer (1) and the lining (2), and the top arch plate (7) is in contact with the radial limiter (4); The top arch plates (7) and the energy absorbing and retracting components (3) are alternately arranged in the axial direction of the lining (2).

4. The energy-type support structure for soft rock large deformation tunnel according to claim 1 is characterized by: It also includes an anchor rod (5), one end of which passes through the support plate (31) and the initial supporting layer (1) in sequence; The anchor rod (5) is slidably connected to the support plate (31).

5. The energy-type support structure for soft rock large deformation tunnel according to claim 4 is characterized in that: A plurality of gas struts (6) corresponding to the anchor rods (5) are installed on the surface of the lining (2), and the gas struts (6) include a gas cavity and a piston.

6. The energy-type support structure for soft rock large deformation tunnel according to claim 1 is characterized by: A connecting rope (8) is connected in series between the plurality of support plates (31), and both ends of the connecting rope (8) are connected to rollers (9).

7. The energy-type support structure for soft rock large deformation tunnel according to claim 6 is characterized by: The roller (9) is installed in a box (10), and openings for connecting the connecting rope (8) are provided on both sides of the box (10). One end of the roller (9) is connected to a spring (11).

8. The energy-type support structure for soft rock large deformation tunnel according to claim 1 is characterized by: It also comprises a guide wheel (12), wherein the guide wheel (12) is arranged on the lower side of the initial supporting layer (1).

9. The energy-type support structure for soft rock large deformation tunnel according to claim 1 is characterized by: A roller (34) is provided at one end of the flap (33) away from the base (32).

Images