Yield supporting method capable of balancing tunnel lining deformation

Abstract

The invention belongs to the field of tunnel supporting, and designs a yielding supporting method capable of balancing tunnel lining deformation, which comprises the following steps of: (1) after a tunnel primary support is finished, arranging a sliding rail device consisting of two L-shaped plates on the surface of the primary support along the axial direction of the tunnel, and fixing the sliding rail device on the surface of the primary support by using a positioning bolt; (2) the sliding rail devices are annularly arranged according to the shape of the tunnel section, and the annular arrangement distance can be flexibly adjusted and controlled according to supporting requirements; (3) two inclined plates with horizontal panels are oppositely placed on the same secondary lining contact plate to form a pressure-bearing retractable balance device, the pressure-bearing retractable balance device slides into a sliding rail device arranged in the axial direction of the tunnel, and the total length of the pressure-bearing retractable balance device sliding into the pressure-bearing retractable balance device is the same as the axial length of the sliding rail device; and (4) after the pressure-bearing retractable balancing device is arranged on the surface of the tunnel primary support, a secondary lining is applied in time. Radial yielding can be achieved, tunnel lining deformation can be balanced, and good supporting performance is achieved.

Description

Technical Field

[0001] The invention belongs to the field of tunnel support and relates to a yield support method capable of balancing the deformation of tunnel lining. Background Art

[0002] In tunnel engineering, different degrees of surrounding rock deformation lead to lining structure damage, which is prone to tunnel collapse accidents. A buffer layer is often selected and placed between the primary support and the secondary lining. It is filled with foam concrete, polyethylene foam board, rubber and plastic sponge and other materials to absorb the deformation of the surrounding rock by its own compression, but its thickness is often thick, resulting in an increase in the thickness of the entire lining structure; in addition, a limiter is also selected. In a soft rock large deformation tunnel, it is placed between the primary support and the secondary lining to resist the large deformation of the surrounding rock with its strength and hollow compressibility in the middle, but its strength is high and its elastic limit is also high. When resisting the deformation of the surrounding rock, it will also cause certain damage to the secondary lining structure. Therefore, it is urgent to make a device with adjustable thickness, less than the thickness of the buffer layer, and with an elastic limit lower than the limiter, so that the thickness of the entire tunnel lining can be reduced, and the secondary lining structure can be better protected while absorbing the deformation of the surrounding rock. Summary of the invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to design a compression support method that can balance the deformation of the tunnel lining. The present invention is achieved through the following technical solutions:

[0004] ① After the primary support of the tunnel is completed, a slide rail device consisting of two "L" plates is arranged on the primary support surface along the axial direction of the tunnel, and fixed to the primary support surface with positioning bolts; ② The slide rail device is arranged circumferentially according to the cross-sectional shape of the tunnel, and the circumferential arrangement spacing can be flexibly adjusted according to the support requirements; ③ The pressure-bearing retractable balancing device composed of two inclined plates with horizontal panels placed opposite to each other on the same secondary lining contact plate is slid into the slide rail device arranged along the axial direction of the tunnel, and the total length of the pressure-bearing retractable balancing device is the same as the axial length of the slide rail device; ④ After the pressure-bearing retractable balancing device is arranged on the primary support surface of the tunnel, the secondary lining is applied in time.

[0005] The short sides of the two "L"-shaped plates of the slide rail device are coplanar and spaced apart, and are placed on the primary support surface of the tunnel, so that 80% to 90% of the area of ​​the slide rail contact plate is exposed to the primary support surface. The deformation of the primary support can press onto the slide rail contact plate, and the distance between the long sides is 3-5mm wider than the slide rail contact plate, ensuring that the pressure-bearing retractable balancing device moves smoothly in the fixed slide rail device, and the height of the long side of the "L"-shaped plate is 70% to 80% of the height of the pressure-bearing retractable balancing device.

[0006] The slide rail device is arranged circumferentially according to the cross-sectional shape of the tunnel, and the circumferential arrangement spacing can be flexibly adjusted according to the support requirements. The pressure-bearing retractable balance device can be arranged in the fixed slide rail device along the tunnel circumference. The arrangement method is determined according to the working conditions and the size of the device. It can be arranged closely or at uniform intervals, and can also be set at key surrounding rock deformation positions such as the arch crown, arch shoulder, arch waist, arch foot, etc.

[0007] The horizontal panel of the inclined plate with the horizontal panel refers to the slide rail contact plate that contacts the slide rail, and the narrow section of the inclined plate and the middle part of the wide section of the slide rail contact plate are welded into a whole.

[0008] The pressure-bearing and retractable balancing device is composed of two slide rail contact plates, two inclined plates with support hinges, a second lining contact plate with support hinges and two compression springs.

[0009] The slide rail contact plate and the inclined plate form an angle "α" in the range of 30° to 60°. The specific angle can be determined within the specified range according to the deformation capacity of the tunnel surrounding rock in actual engineering.

[0010] The slide rail contact plate is parallel to the secondary lining contact plate, and two symmetrical inclined plates are placed on the same secondary lining contact plate. The pressure-bearing and retractable balancing device consists of the secondary lining contact plate, the inclined plate and the slide rail contact plate. The initial support deforms and compresses the slide rail contact plate to move toward the secondary lining contact plate, and the inclined plate and the secondary lining contact end move toward the slide rail contact plate, and the two directions are opposite.

[0011] The inclined plate and the second lining contact plate have overlapping support hinges, and the compression spring is placed between the support hinges on both sides of the second lining contact plate and the inclined plate. The connecting bolts are passed through and fixed with nuts to connect the compression spring, the inclined plate and the second lining contact plate as a whole, so that the compression spring bears pressure to drive the compression of the pressure-bearing and retractable balancing device.

[0012] The two ends of the compression spring are in "U"-shaped surface contact with the inclined plate and the second lining contact plate.

[0013] The slide rail device is arranged along the axial direction of the tunnel, and multiple balancing devices are slid into each slide rail, that is, one side of the slide rail contact plate in the pressure-bearing and retractable balancing device contacts the inside of the short side of the slide rail "L"-shaped plate, and multiple pressure-bearing and retractable balancing devices are smoothly slid in one by one.

[0014] The total length of the sliding device is the same as the length of the slide rail device, ensuring that multiple pressure-bearing and retractable balancing devices are placed in each fixed slide rail device, with no space at both ends, and the second lining contact plate and the second lining are in seamless contact.

[0015] The timely application of secondary lining is to fix the slide rail device and the balancing device between the primary support and the secondary lining to form an integral structure. The deformation of the surrounding rock causes the deformation of the primary support to compress the slide rail contact plate. The pressure is transmitted to the compression spring. The spring compression causes the retractable balancing device to radially compress. The slide rail contact plate moves toward the secondary lining contact plate, and the bottom end of the inclined plate moves toward the primary support until the inclined plate contacts the primary support. The balancing device reaches balance and the deformation of the lining structure stops.

[0016] According to the technical solution of the present invention, a compression support method that can balance the deformation of the tunnel lining mainly includes the following four steps: ① After the initial support of the tunnel is completed, a slide rail device composed of two "L" plates is arranged on the initial support surface along the axial direction of the tunnel, and fixed to the initial support surface with positioning bolts; ② The slide rail device is arranged circumferentially according to the cross-sectional shape of the tunnel, and the circumferential arrangement spacing can be flexibly adjusted according to the support requirements; ③ The pressure-bearing retractable balancing device composed of two inclined plates with horizontal panels is placed opposite to each other on the same secondary lining contact plate, and is slid into the slide rail device arranged along the axial direction of the tunnel, and the total length of the pressure-bearing retractable balancing device is the same as the axial length of the slide rail device; ④ After the pressure-bearing retractable balancing device is arranged on the initial support surface of the tunnel, the secondary lining is applied in time. The above technical solution designs a compression support method that can balance the deformation of the tunnel lining, so that the problems of resisting surrounding rock deformation and protecting the support structure are better solved. In addition, the overall manufacturing process of the present invention is relatively easy to implement, which is convenient for the successful manufacturing of the test model. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an overall schematic diagram of the pressure-bearing retractable balance device placed between the primary support and the secondary lining of the tunnel;

[0018] Figure 2 It is an overall schematic diagram of a pressure-bearing and retractable balancing device placed in a slide rail device;

[0019] Figure 3 It is an isometric diagram of a pressure-bearing and retractable balancing device;

[0020] Figure 4 A side view of a pressure-bearing retractable balancing device

[0021] Figure 5 Front view of the pressure-bearing retractable balance device

[0022] Among them, 1—secondary lining contact plate; 2—inclined plate; 3—support hinge; 4—connecting bolt; 5—slide rail contact plate; 6—compression spring; 7—nut; 8—slide rail device; 9—positioning bolt; 10—secondary lining; 11—primary support; 12—pressure-bearing retractable balancing device DETAILED DESCRIPTION

[0023] The present invention provides a compression support method that can balance the deformation of tunnel lining. In order to make the purpose, technical solution and effect of the invention clearer and more specific, the following uses a schematic diagram to further explain its implementation method in detail. It should be understood that the schematic diagram of the invention described here is only used to explain the invention and is not used to limit the invention. The specific implementation method is as follows:

[0024] ① After the tunnel primary support (11) is completed, a slide rail device (8) composed of two "L" plates is arranged on the surface of the primary support (11) along the axial direction of the tunnel, and is fixed to the surface of the primary support (11) using positioning bolts (9); ② The slide rail device (8) is arranged circumferentially according to the cross-sectional shape of the tunnel, and the circumferential arrangement spacing can be flexibly adjusted according to the support requirements; ③ A pressure-bearing retractable balancing device (12) composed of two inclined plates (2) with horizontal panels are placed oppositely on the same secondary lining contact plate (1) and is slid into the slide rail device (8) arranged along the axial direction of the tunnel, and the total length of the pressure-bearing retractable balancing device (12) is the same as the axial length of the slide rail device (8); ④ After the pressure-bearing retractable balancing device (12) is arranged on the surface of the tunnel primary support (11), the secondary lining (10) is applied in time.

[0025] The short sides of the two "L"-shaped plates of the slide rail device (8) are coplanar and spaced apart, and are placed on the surface of the tunnel primary support (11) and fixed with positioning bolts (9) so that 90% of the area of ​​the slide rail contact plate (5) is exposed on the surface of the primary support (11). The distance between the long sides of the "L"-shaped plates is 4 mm wider than the width of the slide rail contact plates (5). The height of the long side of the "L"-shaped plate is 70% of the height of the pressure-bearing retractable balancing device (12).

[0026] The slide rail devices (8) are arranged in pairs in a close proximity along the tunnel annular direction.

[0027] The slide rail contact plate (5) and the inclined plate (2) in the pressure-bearing and retractable balancing device (12) are welded as a whole at an angle of 45 degrees, and the slide rail contact plate (5) is parallel to the second lining contact plate (1).

[0028] Two inclined plates (2) in the pressure-bearing retractable balancing device (12) are symmetrically placed on the same second lining contact plate (1), and the two inclined plates (2) are respectively connected to a slide rail contact plate (5). The primary support (11) deforms and compresses the slide rail contact plate (5), so that the slide rail contact plate (5) moves toward the second lining contact plate (1), and the contact end of the inclined plate (2) and the second lining contact plate (1) moves toward the slide rail contact plate (5), and the two directions are opposite.

[0029] The inclined plate (2) and the second lining contact plate (1) support hinge (3) overlap, and the compression spring (6) is placed between the second lining contact plate (1) and the support hinge (3) on both sides of the inclined plate (2), and connected with the connecting bolt (4) and fixed with the nut (7).

[0030] The two ends of the compression spring (6) are in a "U" shape and are in surface contact with the inclined plate (2) and the second lining contact plate (1). The compression spring (6) bears pressure to drive the compression of the pressure-bearing and retractable balancing device (12).

[0031] One side of the slide rail contact plate (5) in the pressure-bearing retractable balancing device (12) is brought into contact with the inner side of the short side of the "L"-shaped plate of the slide rail device (8), and a plurality of pressure-bearing retractable balancing devices (12) are smoothly slid in sequentially, ensuring that a plurality of pressure-bearing retractable balancing devices (12) are placed in each fixed slide rail device (8) with no space at both ends, and the second lining contact plate (1) is in seamless contact with the second lining (10).

[0032] The tunnel secondary lining (10) is installed, and the slide rail device (8) and the pressure-bearing and retractable balancing device (12) are completely fixed between the tunnel primary support (11) and the secondary lining (10), so that the primary support (11), the slide rail device (8), the pressure-bearing and retractable balancing device (12), the secondary lining (10) and the surrounding rock are fixed as a whole.

[0033] The deformation of the surrounding rock forces the primary support (11) to deform and press onto the slide rail contact plate (5). The slide rail contact plate (5) and the inclined plate (2) transmit the pressure to the compression spring (6). The compression spring (6) is compressed to radially compress the pressure-bearing retractable balancing device (12). The slide rail contact plate (5) and the inclined plate (2) move toward each other until the inclined plate (2) also contacts the deformed surface of the primary support (11). At this time, the pressure-bearing retractable balancing device (12) reaches equilibrium, so that the deformation of the lining structure stops.

[0034] The above is only a preferred specific implementation. The protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention.

Claims

1. A yield support method for balancing tunnel lining deformation, the construction of which includes the following steps: ① After the primary support of the tunnel is completed, a slide rail device consisting of two "L" plates is arranged on the primary support surface along the axial direction of the tunnel, and fixed to the primary support surface with positioning bolts; ② The slide rail device is arranged circumferentially according to the cross-sectional shape of the tunnel, and the circumferential arrangement spacing can be flexibly adjusted according to the support requirements; ③ The pressure-bearing retractable balancing device composed of two inclined plates with horizontal panels placed opposite to each other on the same secondary lining contact plate is slid into the slide rail device arranged along the axial direction of the tunnel, and the total length of the pressure-bearing retractable balancing device is the same as the axial length of the slide rail device; ④ After the pressure-bearing retractable balancing device is arranged on the primary support surface of the tunnel, the secondary lining is applied in time; The two "L"-shaped plates have their short sides coplanar and spaced apart, so that 80% to 90% of the area of ​​the slide rail contact plate is exposed to the primary support surface, and the distance between their long sides is 3-5mm wider than the slide rail contact plate, and the height of the long side of the "L"-shaped plate is 70% to 80% of the height of the pressure-bearing retractable device; The circumferential arrangement spacing of the slide rail device can be flexibly adjusted according to the support requirements. It can be closely attached or evenly spaced, and can also be set at key surrounding rock deformation positions such as arch crown, arch shoulder, arch waist, arch foot, etc. The inclined plate with a horizontal panel, wherein the horizontal panel refers to a slide rail contact plate in contact with the slide rail; The pressure-bearing and retractable balancing device is composed of two slide rail contact plates, two inclined plates with support hinges, a second lining contact plate with support hinges and two compression springs; The slide rail contact plate is at an angle "α" with the inclined plate, is parallel to the second lining contact plate, and the narrow section of the inclined plate is welded to the middle of the wide section of the slide rail contact plate as a whole, and the angle α is 30° to 60°; The compression spring is placed between the second lining contact plate and the hinges on both sides of the inclined plate, and is connected and fixed by connecting bolts. Its two ends are in "U" shape and surface contact with the inclined plate and the second lining contact plate.

2. A yield support method capable of balancing tunnel lining deformation according to claim 1, characterized in that: 80% to 90% of the area of ​​the slide rail contact plate is exposed on the primary support surface. The deformation of the surrounding rock causes the deformation of the primary support to compress the slide rail contact plate. The pressure is transmitted to the compression spring. The spring compression causes the retractable balancing device to radially compress. The slide rail contact plate moves toward the secondary lining contact plate, and the bottom end of the inclined plate moves toward the primary support until the inclined plate contacts the primary support, the balancing device reaches balance, and the deformation of the lining structure stops.

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