A support device and method for a cave tunnel buried in a weak surrounding rock floor

Abstract

The present invention discloses a supporting device and method for a cave tunnel buried in a weak surrounding rock floor, belonging to the field of tunnels. The present invention discloses a supporting device for a cave tunnel buried in a weak surrounding rock floor, comprising an annular groove arranged on the outer wall of the tunnel vault and an annular sleeve arranged in the annular groove, and also comprising a support seat arranged at the bottom of the tunnel, wherein the bottom of the support seat is provided with a plurality of support columns fixed to the bottom of the cave, and the annular sleeve passes through the support seat and extends to the bottom of the tunnel; a tension steel wire rope is arranged in the annular sleeve, a fixed pulley is arranged in the support column, and a tension adjustment component is arranged in the support seat, and the end of the tension steel wire rope passes through the fixed pulley and is connected to the tension adjustment component. The top of the tunnel is used to provide a certain tension, and the tension is transmitted to the support column through the tension steel wire rope, so as to improve the stress condition of the support column, thereby improving the stability of the support column in the cave.

Description

Technical Field

[0001] The present invention relates to the field of tunnel engineering, and in particular to a supporting device and method for a karst tunnel buried in a soft surrounding rock floor. Background Art

[0002] Some current projects need to deal with a large number of engineering problems caused by karst geology, especially karst tunnel engineering problems. Due to the improvement of railway design standards, the longitudinal slope and curve radius of the line are limited, and long, deep-buried karst tunnels are inevitable. At the same time, due to the limitations of survey technology and survey cycle and the irregularity of karst development itself, it is difficult to fully identify the specific karst morphology of the tunnel during the survey and design stage. The probability of encountering karst of different forms and volumes and different hazards during tunnel construction is extremely high. Therefore, during the construction of karst tunnels, there are deep-buried caves under the tunnel floor. How to treat the deep-buried caves and ensure construction quality and operational safety is extremely important.

[0003] The weak surrounding rock floor cannot provide strong support, making the tunnel prone to deformation and damage. Summary of the invention

[0004] In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to propose a supporting device for a karst cave tunnel buried in a soft surrounding rock floor, which can effectively support the tunnel body and avoid the unstable influence of the karst cave on the tunnel.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] The present invention provides a support device for a cave tunnel buried in a weak surrounding rock floor, comprising an annular groove arranged on the outer wall of the tunnel arch and an annular sleeve arranged in the annular groove, and also comprising a support seat arranged at the bottom of the tunnel, wherein a plurality of support columns fixed to the bottom of the cave are arranged at the bottom of the support seat, and the annular sleeve extends through the support seat to the bottom of the tunnel; a tension steel wire rope is arranged in the annular sleeve, a fixed pulley is arranged in the support column, and a tension adjustment component is arranged in the support seat, and the end of the tension steel wire rope passes through the fixed pulley and is connected to the tension adjustment component.

[0007] The preferred technical solution of the present invention is that the annular casing is provided with a plurality of through holes in the radial direction, grouting conduits are provided in the through holes, the plurality of grouting conduits are evenly arranged along the circumference of the annular casing, one end of the grouting conduit is fixedly connected to the annular casing and the tunnel vault wall, and the other end of the grouting conduit passes through the annular casing and extends into the rock mass.

[0008] A preferred technical solution of the present invention is that the annular casing is filled with concrete, and the tension steel wire rope and the grouting conduit are simultaneously solidified in the concrete in the annular casing.

[0009] The preferred technical solution of the present invention is that the support column is located on both sides of the support seat, a through groove is provided on the support column, the fixed pulley is located in the through groove, and the end of the tension wire rope passes through the fixed pulley on one side and goes around the fixed pulley on the other side.

[0010] The preferred technical solution of the present invention is that the tension adjustment assembly includes an adjusting threaded column and a threaded sleeve fixed inside the support seat, a connecting hole is provided in the middle of the adjusting threaded column, the tension wire rope passes through the connecting hole and is fixedly connected to the end of the adjusting threaded column, and the adjusting threaded column is threadedly connected to the threaded sleeve.

[0011] A construction method using the soft surrounding rock bottom plate buried karst cave tunnel support device comprises the following steps: step S00: pre-reserving an annular groove on the tunnel lining sheet, first installing and fixing the annular sleeve on the tunnel top, and then installing the lining sheet so that the annular sleeve is located in the annular groove; step S10: constructing the tunnel bottom surface, using a template to cast and form a support column, and pre-embedding and installing a fixed pulley in the middle of the support column; step S20: casting a tunnel support seat, pre-embedding a threaded sleeve; step S30: passing a tension steel wire rope through the annular sleeve, and after passing through the fixed pulley, connecting it with an adjusting threaded column in the threaded sleeve; step S40: grouting the annular sleeve to fix the tension steel wire rope, and rotating the adjusting threaded column after solidification to further adjust the tension.

[0012] The preferred technical solution of the present invention is that in step S30, the tension wire rope is wound from the fixed pulley on one side to the fixed pulley on the other side, and then the tension is initially applied by the tension equipment and fixedly connected to the adjusting threaded column, and then threaded into the threaded sleeve.

[0013] The beneficial effects of the present invention are:

[0014] The present invention provides a support device for a cave tunnel buried in a weak surrounding rock floor, comprising an annular groove arranged on the outer wall of the tunnel vault and an annular sleeve arranged in the annular groove, and also comprising a support seat arranged at the bottom of the tunnel, wherein the bottom of the support seat is provided with a plurality of support columns fixed to the bottom of the cave, and the annular sleeve extends through the support seat to the bottom of the tunnel; a tension steel wire rope is arranged in the annular sleeve, a fixed pulley is arranged in the support column, and a tension adjustment component is arranged in the support seat, and the end of the tension steel wire rope passes through the fixed pulley and is connected to the tension adjustment component. The top of the tunnel is used to provide a certain tension, and the tension is transmitted to the support column through the tension steel wire rope, so as to improve the stress condition of the support column, thereby improving the stability of the support column in the cave. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is an overall schematic diagram of a supporting device for a cave tunnel buried in a soft surrounding rock floor provided in a specific embodiment of the present invention;

[0016] Figure 2 is a cross-sectional schematic diagram of the installation of a fixed pulley provided in a specific embodiment of the present invention;

[0017] In the figure:

[0018] 11. Annular groove; 2. Annular sleeve; 3. Grouting conduit; 4. Support seat; 5. Support column; 6. Tension wire rope; 7. Tension adjustment assembly; 8. Fixed pulley; 21. Through hole; 51. Through groove; 71. Threaded sleeve; 72. Adjustment threaded column. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0020] like Figure 1-2 As shown, this embodiment provides a support device for a cave tunnel buried in a weak surrounding rock floor, comprising an annular groove 11 arranged on the outer wall of the tunnel vault and an annular sleeve 2 arranged in the annular groove 11, and also comprising a support seat 4 arranged at the bottom of the tunnel, wherein the bottom of the support seat 4 is provided with a plurality of support columns 5 fixed to the bottom of the cave, and the annular sleeve 2 extends through the support seat 4 to the bottom of the tunnel; a tension steel wire rope 6 is arranged in the annular sleeve 2, a fixed pulley 8 is arranged in the support column 5, and a tension adjustment component 7 is arranged in the support seat 4, and the end of the tension steel wire rope 6 passes through the fixed pulley 8 and is connected to the tension adjustment component 7. The annular sleeve 2 is arranged outside the vault, and can evenly provide sufficient tension to the tension steel wire rope 6 inside with the help of the force of the vault. The bottom of the tunnel is supported by the support extending to the bottom of the cave, and the force is dispersed by the support seat 4. The fixed end point of the tension wire rope 6 is located in the support seat 4, and the support column 5 bears the force through the fixed pulley 8, so that when the rock mass at the bottom of the support column 5 deviates, the tension wire rope 6 will not be directly pulled in one direction, but the fixed pulley 8 will provide a constant directional force to avoid excessive tension causing tunnel damage. At the same time, the tension wire rope 6 can provide a large vertical force to the support column 5 through the fixed pulley 8, which will increase the vertical force when tilted, reducing the harm caused by the tilt.

[0021] Furthermore, the annular sleeve 2 is provided with a plurality of through holes 21 in the radial direction, and a grouting conduit 3 is provided in the through hole 21. The plurality of grouting conduits 3 are evenly arranged along the circumference of the annular sleeve 2. One end of the grouting conduit 3 is fixedly connected to the annular sleeve 2 and the wall of the tunnel vault, and the other end of the grouting conduit 3 extends into the rock mass through the annular sleeve 2. By inserting the grouting conduit 3 into the rock mass, the pulling force on the annular sleeve 2 can be increased, and the pulling force of the annular sleeve 2 can be prevented from being excessively applied to the vault, thereby maintaining the stability of the tunnel.

[0022] Preferably, the annular sleeve 2 is filled with concrete, and the tension wire rope 6 and the grouting conduit 3 are simultaneously solidified in the concrete in the annular sleeve 2. The tension wire rope 6 and the annular sleeve 2 are connected as a whole by concrete, so that the force can be better conducted.

[0023] Preferably, the support column 5 is located on both sides of the support seat 4, and a through groove 51 is provided on the support column 5. The fixed pulley 8 is located in the through groove 51, and the end of the tension wire rope 6 passes through the fixed pulley 8 on one side and is wound around the fixed pulley 8 on the other side. The tension wire rope 6 passes from the fixed pulley 8 on one side to the fixed pulley 8 on the other side, and a lateral force can be applied to one fixed pulley 8, and a vertical force can be applied to the other fixed pulley 8. Under the action of the tension wire ropes 6 at both ends, a good force balance can be maintained.

[0024] Preferably, the tension adjustment assembly 7 includes an adjustment threaded column 72 and a threaded sleeve 71 fixed inside the support seat 4, a connection hole is provided in the middle of the adjustment threaded column 72, the tension wire rope 6 passes through the connection hole and is fixedly connected to the end of the adjustment threaded column 72, and the adjustment threaded column 72 is threadedly connected to the threaded sleeve 71. The tension can be conveniently adjusted by rotating the adjustment threaded column 72, and can be adjusted in time when the support column 5 is tilted.

[0025] A construction method using the soft surrounding rock floor buried cave tunnel support device includes the following steps: step S00: pre-reserving an annular groove 11 on the tunnel lining sheet, first installing and fixing the annular sleeve 2 on the tunnel top, and then installing the lining sheet so that the annular sleeve 2 is located in the annular groove 11; step S10: constructing the tunnel bottom surface, using the template to cast and form the support column 5, and pre-embed the fixed pulley 8 in the middle of the support column; step S20: casting the tunnel support seat 4, pre-embed the threaded sleeve 71; step S30: passing the tension wire rope 6 through the annular sleeve 2, and after passing through the fixed pulley 8, connecting with the adjustment threaded column 72 in the threaded sleeve 71; step S40: grouting the annular sleeve 2 to fix the tension wire rope 6, and rotating the adjustment threaded column 72 after solidification to further adjust the tension. When the support column 5 is constructed, the tension wire rope 6 can provide a certain tension, so that the template is better stressed.

[0026] Preferably, in step S30, the tension wire rope 6 is wound from the fixed pulley 8 on one side to the fixed pulley 8 on the other side, and then is fixedly connected to the adjusting threaded column 72 after preliminary tension is applied by a tension device, and then is threaded into the threaded sleeve 71.

[0027] The present invention is described by preferred embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. The present invention is not limited to the specific embodiments disclosed herein, and other embodiments falling within the claims of this application are within the scope of protection of the present invention.

Claims

1. A supporting device for a cave tunnel buried in a soft surrounding rock floor, characterized in that: It comprises an annular groove (11) arranged on the outer side wall of the tunnel vault and an annular sleeve (2) arranged in the annular groove (11), and also comprises a support seat (4) arranged at the bottom of the tunnel, a plurality of support columns (5) fixed to the bottom of the cave are arranged at the bottom of the support seat (4), and the annular sleeve (2) passes through the support seat (4) and extends to the bottom of the tunnel; A tension steel wire rope (6) is arranged in the annular sleeve (2), a fixed pulley (8) is arranged in the support column (5), a tension adjustment component (7) is arranged in the support seat (4), and an end of the tension steel wire rope (6) passes through the fixed pulley (8) and is connected to the tension adjustment component (7).

2. The supporting device for a cave tunnel buried in a weak surrounding rock floor according to claim 1 is characterized in that: The annular sleeve (2) is provided with a plurality of through holes (21) in the radial direction, a grouting conduit (3) is provided in the through hole (21), the plurality of grouting conduits (3) are evenly arranged along the circumference of the annular sleeve (2), one end of the grouting conduit (3) is fixedly connected to the annular sleeve (2) and the tunnel vault wall, and the other end of the grouting conduit (3) passes through the annular sleeve (2) and extends into the rock mass.

3. The supporting device for a cave tunnel buried in a weak surrounding rock floor according to claim 2 is characterized in that: The annular casing (2) is filled with concrete, and the tension steel wire rope (6) and the grouting conduit (3) are simultaneously solidified in the concrete in the annular casing (2).

4. The supporting device for a cave tunnel buried in a weak surrounding rock floor according to claim 1 is characterized in that: The support column (5) is located on both sides of the support seat (4), and a through groove (51) is provided on the support column (5). The fixed pulley (8) is located in the through groove (51), and the end of the tension steel wire rope (6) passes through the fixed pulley (8) on one side and is wound around the fixed pulley (8) on the other side.

5. The supporting device for a cave tunnel buried in a weak surrounding rock floor according to claim 4 is characterized in that: The tension adjustment assembly (7) comprises an adjustment threaded column (72) and a threaded sleeve (71) fixed inside the support seat (4); a connecting hole is provided in the middle of the adjustment threaded column (72); the tension steel wire rope (6) passes through the connecting hole and is fixedly connected to the end of the adjustment threaded column (72); the adjustment threaded column (72) is threadedly connected to the threaded sleeve (71).

6. A construction method using the support device for a cave tunnel buried in a weak surrounding rock floor as claimed in claim 5, characterized in that: The method comprises the following steps: Step S00: reserving an annular groove (11) on a tunnel lining sheet, first installing and fixing an annular sleeve (2) on the top of the tunnel, and then installing the lining sheet so that the annular sleeve (2) is located in the annular groove (11); Step S10: constructing the tunnel bottom surface, using a formwork to cast and form a support column (5), and pre-embed a fixed pulley (8) in the middle of the support column; Step S20: casting the tunnel support seat (4) and pre-embed the threaded sleeve (71); Step S30: passing the tension steel wire rope (6) through the annular sleeve (2), and then through the fixed pulley (8) and connected to the adjusting threaded column (72) in the threaded sleeve (71); Step S40: injecting grout into the annular casing (2) to fix the tension steel wire rope (6), and rotating the adjusting threaded column (72) to further adjust the tension after solidification.

7. The construction method for supporting a tunnel in a cave buried in a soft surrounding rock floor according to claim 6 is characterized in that: In step S30, the tension wire rope (6) is wound from the fixed pulley (8) on one side to the fixed pulley (8) on the other side, and then initially tension is applied by a tension device to fix the tension wire rope with the adjusting threaded column (72), and then threadedly connected into the threaded sleeve (71).

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