CN112696213B - Tunnel supporting structure and construction method thereof - Google Patents

Abstract

The invention discloses a tunnel supporting structure, which comprises a first supporting part and a second supporting part which are arranged at intervals; the first supporting part comprises a first steel frame, flexible bases are fixed at two ends of the top of the first steel frame, a first bracket is fixed between the two flexible bases, a steel plate is fixed at the top of the first bracket and is in contact with the inner wall of the tunnel, a plurality of bolts are in threaded connection with the first bracket, blind holes which are in one-to-one correspondence with the bolts are formed in the bottom surface of the steel plate, and the tops of the bolts and the blind holes are in mutual compression joint; the second supporting part comprises a second steel frame, a second bracket is fixed to the top of the second steel frame, the second bracket is fixedly connected with the adjacent first bracket through an inclined beam, and the top of the second bracket is fixedly connected with the inner wall of the tunnel through an anchor rod. The invention can improve the defects of the prior art and improve the construction efficiency of supporting operation.

Description

A tunnel support structure and its construction method

technical field

The invention relates to the technical field of tunnel excavation construction, in particular to a tunnel support structure and a construction method thereof.

Background technique

In order to ensure the stability and safety of the working face during tunnel excavation, it is necessary to support the excavated working face. In order to reduce the influence of the stress and deformation of the working face on the support structure, the prior art usually adopts two or more support construction methods to release the stress of the working face. Due to the need for multiple repeated support operations, this method has the problems of a large total amount of construction and a long construction time.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a tunnel support structure and its construction method, which can solve the deficiencies of the prior art and improve the construction efficiency of the support operation.

In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows.

A tunnel support structure, including a first support part and a second support part arranged at intervals; the first support part includes a first steel frame, the two ends of the top of the first steel frame are fixed with flexible bases, two The first bracket is fixed between the flexible bases, the top of the first bracket is fixed with a steel plate, the steel plate is in contact with the inner wall of the tunnel, a number of bolts are threaded on the first bracket, and the bottom surface of the steel plate is provided with one-to-one correspondence with the bolts. Blind hole, the top of the bolt and the blind hole are crimped with each other; the second supporting part includes a second steel frame, the top of the second steel frame is fixed with a second bracket, and the gap between the second bracket and the adjacent first bracket The inclined beam is fixedly connected, and the top of the second bracket is fixedly connected with the inner wall of the tunnel through the anchor rod.

Preferably, the flexible base includes a housing, an oil chamber is provided at the bottom of the housing, a piston rod is movably inserted into the top of the oil chamber, a base plate is fixed on the top of the piston rod, and a torsion rod is installed between the base plate and the side wall and the housing. Spring, the bottom of the base plate is provided with a tapered part, the top of the housing is provided with an annular flow channel, the annular flow channel communicates with the oil chamber, the top of the annular flow channel is movably inserted with a piston ring, and the piston ring is crimped with the tapered part Cooperate.

Preferably, an axial grouting hole is arranged in the anchor rod.

Preferably, several orifice plates are fixed on the side wall of the anchor rod, and the angle between the orifice plate and the anchor rod is 15°.

Preferably, first screw rods are symmetrically fixed on both sides of the anchor rod, and the first screw rods are fixed on the second bracket through nuts.

A kind of construction method of above-mentioned tunnel support structure, comprises the following steps:

Fix the first steel frame at the preset support position of the first support part, and reserve the installation space for the second steel frame, and make the steel plate contact the inner wall of the tunnel evenly by adjusting the bolts, and keep it for 12 hours;

B. Spray the concrete layer on the supporting surface;

C. After the concrete layer is solidified, drill and fix the anchor rod at the support position of the preset second support part, fix the second steel frame between the two adjacent first steel frames, and then connect the anchor rod with the The second bracket is fixed;

D. Use inclined beams to connect the second bracket to the adjacent first bracket.

The beneficial effect of adopting the above-mentioned technical scheme is that: the present invention arranges two supporting parts at intervals and carries out distributed construction, and the construction amount of each construction is half of the total length of the supporting, so that the total construction length of the two constructions is one The total support length greatly reduces the support construction length compared with the prior art. After the support operation of the first support part, the flexible base is used to effectively buffer the deformation stress of the support work surface, and then the second support part is used for rigid support, and at the same time, the first support part is connected Reinforced to ensure the stability of the entire supporting structure. The interconnected annular flow channels and oil chambers in the flexible base can perform axial and radial synchronous support after the substrate is stressed, improving the support stability of the flexible base.

Description of drawings

Fig. 1 is a schematic diagram of two supporting parts in the radial direction of the tunnel in a specific embodiment of the present invention.

Fig. 2 is a structural diagram of the first bracket in a specific embodiment of the present invention.

Fig. 3 is a structural diagram of a flexible base in a specific embodiment of the present invention.

Fig. 4 is a structural diagram of an anchor rod in a specific embodiment of the present invention.

In the figure: 1. First steel frame; 2. Flexible base; 3. First bracket; 4. Steel plate; 5. Bolt; 6. Blind hole; 7. Second steel frame; 8. Second bracket; 9. Inclined beam; 10. Anchor rod; 11. Shell; 12. Oil chamber; 13. Piston column; 14. Base plate; 15. Torsion spring; 16. Tapered part; Ring; 19, grouting hole; 20, orifice plate; 21, first screw rod; 22, threaded hole; 23, screw sleeve; 24, second screw rod; 25, nut.

Detailed ways

The standard parts used in the present invention can be purchased from the market, and the special-shaped parts can be customized according to the instructions and the accompanying drawings. The specific connection methods of each part adopt mature bolts, rivets, welding in the prior art , pasting and other conventional means, no longer described in detail here.

Referring to Figures 1-4, a specific embodiment of the present invention includes a first supporting part and a second supporting part arranged at intervals; the first supporting part includes a first steel frame 1, and the two ends of the top of the first steel frame 1 are fixed There are flexible bases 2, a first bracket 3 is fixed between the two flexible bases 2, a steel plate 4 is fixed on the top of the first bracket 3, the steel plate 4 is in contact with the inner wall of the tunnel, and the first bracket 3 is threaded with a Several bolts 5, blind holes 6 corresponding to the bolts 5 are provided on the bottom surface of the steel plate 4, and the tops of the bolts 5 and the blind holes 6 are pressed together; the second supporting part includes a second steel frame 7, and the second steel frame 7 A second bracket 8 is fixed on the top, and the second bracket 8 is fixedly connected to the adjacent first bracket 3 through an inclined beam 9 , and the top of the second bracket 8 is fixedly connected to the inner wall of the tunnel through an anchor rod 10 .

A kind of construction method of above-mentioned tunnel support structure is characterized in that comprising the following steps:

A. Fix the first steel frame 1 at the support position of the preset first support part, and reserve the installation space for the second steel frame 7, and adjust the bolt 5 to make the steel plate 4 evenly contact with the inner wall of the tunnel, and keep it for 12 hours ;

B. Spray the concrete layer on the supporting surface;

C. After the concrete layer is solidified, drill and fix the anchor rod 10 at the support position of the preset second support part, fix the second steel frame 7 between the adjacent two first steel frames 1, and then place the The anchor rod 10 is fixed to the second bracket 8;

D. Connect the second bracket 8 with the adjacent first bracket 3 by using the inclined beam 9 .

An axial grouting hole 19 is arranged in the anchor rod 10 . A plurality of orifice plates 20 are fixed on the side wall of the anchor rod 10, and the angle between the orifice plates 20 and the anchor rod 10 is 15°. Both sides of the anchor rod 10 are symmetrically fixed with first screw rods 21 , and the first screw rods 21 are fixed on the second bracket 8 through nuts 25 .

In step C, the hole diameter of the support position is interference-fitted with the outer edge of the orifice plate 20. During the process of embedding the anchor rod 10 into the perforated position, concrete is injected into the perforated position through the grouting hole 19 synchronously. During the embedding process of the rod 10, the anchor rod 10 is rotated to ensure sufficient and uniform contact between the concrete in the hole and the orifice plate. When the concrete curing strength reaches 30% of the fully cured strength, fixing the anchor rod 10 with the first screw rod 21 and the second bracket 8 can reduce the local stress and deformation generated during the fixing process of the anchor rod 10 .

The flexible base 2 includes a housing 11, the bottom of the housing 11 is provided with an oil chamber 12, the top of the oil chamber 12 is movably inserted with a piston rod 13, the top of the piston rod 13 is fixed with a base plate 14, and the side wall of the base plate 14 and the housing 11 A torsion spring 15 is installed between them, the bottom of the base plate 14 is provided with a tapered portion 16, the top of the housing 11 is provided with an annular flow channel 17, the annular flow channel 17 communicates with the oil chamber 12, and the top of the annular flow channel 17 is movable A piston ring 18 is connected, and the piston ring 18 is press-fitted with the tapered portion 16 .

Threaded holes 22 are arranged symmetrically on the edge of the base plate 14 , and a screw sleeve 23 is hinged below the inclined beam 9 . When the inclined beam 9 is installed, the inclined beam 9 and the base plate 14 are connected through the second screw rod 24, and the flexible base 2 can be used for long-term buffering and absorption of the stress and deformation of the supporting structure after the construction is completed, so as to improve the stability of the supporting structure. stability.

In describing the present invention, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", The orientations or positional relationships indicated by "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention, rather than indicating or It should not be construed as limiting the invention by implying that a referenced device or element must have a particular orientation, be constructed, and operate in a particular orientation.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. What are described in the above-mentioned embodiments and the description only illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have Variations and improvements are possible, which fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (6)

1. A tunnel support structure is characterized in that: comprise the first support part and the second support part that are arranged at intervals; The first support part comprises the first steel frame (1), the first steel frame (1) Flexible bases (2) are fixed at both ends of the top, a first bracket (3) is fixed between the two flexible bases (2), a steel plate (4) is fixed on the top of the first bracket (3), and the steel plate ( 4) In contact with the inner wall of the tunnel, several bolts (5) are threaded on the first bracket (3), and the bottom surface of the steel plate (4) is provided with blind holes (6) corresponding to the bolts (5), and the bolts ( 5) and the blind hole (6) are crimped with each other; the second supporting part includes a second steel frame (7), and the top of the second steel frame (7) is fixed with a second bracket (8), and the second bracket (8) is fixedly connected to the adjacent first bracket (3) through an inclined beam (9), and the top of the second bracket (8) is fixedly connected to the inner wall of the tunnel through an anchor rod (10). 2. The tunnel support structure according to claim 1, characterized in that: the flexible base (2) comprises a shell (11), the bottom of the shell (11) is provided with an oil chamber (12), the oil chamber ( 12) A piston rod (13) is movably plugged on the top, a base plate (14) is fixed on the top of the piston rod (13), and a torsion spring (15) is installed between the side wall of the base plate (14) and the housing (11). The bottom of (14) is provided with a tapered portion (16), the top of the housing (11) is provided with an annular flow channel (17), the annular flow channel (17) communicates with the oil chamber (12), and the annular flow channel (17) ) is movably plugged with a piston ring (18), and the piston ring (18) is crimped with the taper (16). 3. The tunnel support structure according to claim 1, characterized in that: axial grouting holes (19) are arranged in the anchor rod (10). 4. The tunnel support structure according to claim 3, characterized in that: several orifice plates (20) are fixed on the side wall of the anchor rod (10), and the clip between the orifice plate (20) and the anchor rod (10) The angle is 15°. 5. The tunnel support structure according to claim 4, characterized in that: the first screw rod (21) is fixed symmetrically on both sides of the anchor rod (10), and the first screw rod (21) is fixed on the on the second bracket (8). 6. A construction method for the tunnel support structure described in any one of claims 1-5, characterized in that it comprises the following steps: A. Fix the first steel frame (1) at the support position of the preset first support part, and reserve the installation space for the second steel frame (7), and adjust the bolt (5) to make the steel plate (4) and Even contact with the inner wall of the tunnel for 12 hours; B. Spray the concrete layer on the supporting surface; C. After the concrete layer is solidified, drill and fix the anchor rod (10) at the support position of the preset second support part, and fix the second steel frame between the two adjacent first steel frames (1) (7), then the anchor rod (10) is fixed with the second bracket (8); D. Connect the second bracket (8) with the adjacent first bracket (3) by using inclined beams (9).

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