A yielding device for a soft rock tunnel support structure

Abstract

The utility model discloses a kind of yielding device for soft rock tunnel supporting structure, including mutually facing first elliptical tube, second elliptical tube;The first elliptical tube is rotatably connected with second elliptical tube, and rotation axis passes first elliptical tube end face center point and second elliptical tube end face center point.The utility model provides a kind of yielding device for soft rock tunnel supporting structure, to solve the problem that yielding device in prior art is difficult to deal with long-term rheological deformation in tunnel operation process, realize the purpose of improving the adaptability of yielding device to high stress soft rock tunnel.

Description

Technical Field

[0001] This utility model relates to the field of tunnel surrounding rock deformation control, specifically to a pressure relief device for soft rock tunnel support structures. Background Technology

[0002] For tunnel construction in soft rock under high ground stress, large deformation of weak surrounding rock is a significant engineering challenge. Monitoring data from multiple tunnels show that the final deformation of weak surrounding rock under high ground stress conditions can typically reach over 30 cm, and in some cases even over 1 meter.

[0003] Traditional techniques typically employ grouting to control the loosening and deformation of the surrounding rock in soft rock tunnels. However, this traditional method suffers from drawbacks such as difficulty in controlling the grouting effect and significant delays in construction progress. Existing technologies have also developed some measures to improve and optimize the support structure to resist surrounding rock deformation; however, these existing technologies have the following drawbacks under high-stress soft rock conditions:

[0004] Within the tunnel's lifespan, surrounding rock deformation can be categorized into "short-term compressive deformation" and "long-term rheological deformation" based on the deformation time. Short-term compressive deformation refers to the deformation of the surrounding rock during tunnel excavation and support; long-term rheological deformation refers to the deformation of the surrounding rock during tunnel operation. During tunnel excavation and support, which is the process of "short-term compressive deformation," the rate of stress release is rapid, the deformation rate of the surrounding rock is large, and the deformation amount is also significant, leading to an increase in the deformation of the initial support structure. When the deformation of the initial support structure is excessive, it can lead to a decrease in the bearing capacity of the support structure, or even failure, resulting in loss of load-bearing capacity. Soft rock under high ground stress conditions typically exhibits rheological properties; that is, as time increases, the rheological deformation of the surrounding rock gradually increases, causing increasing pressure on the support structure and leading to frequent problems such as cracking in the support structure later on. Existing pressure-relieving devices have weak adaptability to the above conditions and are insufficient to cope with the long-term rheological deformation during tunnel operation. Utility Model Content

[0005] This invention provides a pressure-relief device for soft rock tunnel support structures, which solves the problem that existing pressure-relief devices are unable to cope with long-term rheological deformation during tunnel operation, thereby improving the adaptability of the pressure-relief device to soft rock tunnels with high ground stress.

[0006] This utility model is achieved through the following technical solution:

[0007] A pressure-relief device for soft rock tunnel support structures includes a first elliptical tube and a second elliptical tube with their end faces facing each other; the first elliptical tube and the second elliptical tube are rotatably connected, and the axis of rotation passes through the center point of the end face of the first elliptical tube and the center point of the end face of the second elliptical tube.

[0008] To address the problem that existing pressure-relief devices are insufficient to handle long-term rheological deformation during tunnel operation, this invention proposes a pressure-relief device for soft rock tunnel support structures. The first and second elliptical tubes are pipe structures with elliptical cross-sections. When radial pressure is required on the pressure-relief component, the major axes of the first and second elliptical tubes are oriented towards the radial direction of the tunnel; when circumferential pressure is required, the major axes of the first and second elliptical tubes are perpendicular to the radial direction of the tunnel. This application uses an elliptical pipe structure as the pressure-relief component, which increases the deformation range of the component, thereby increasing the absorption of surrounding rock loads (including compressive and rheological deformation).

[0009] Furthermore, existing technologies employ two methods for bearing pressure within the initial support: one using purely rigid components, and the other using flexible or elastic systems to dissipate energy. Purely rigid components have low toughness, making them prone to torsion or fracture failure and loss of load-bearing capacity when encountering significant surrounding rock deformation. Flexible or elastic systems, on the other hand, are less resistant to later-stage rheological deformation of the surrounding rock. The pressure-relief component designed in this scheme allows the first and second elliptical tubes to rotate relative to each other, with their rotation axes passing through the center points of both the first and second elliptical tube end faces. Therefore, when the first and second elliptical tubes rotate relative to each other, they become misaligned and no longer directly opposite each other. This process compresses the external concrete, consuming a significant amount of energy, which helps to dissipate the rheological deformation generated during tunnel operation within the support structure, extending the tunnel's service life and maintenance cycle. Moreover, the structure composed of the two elliptical tubes can only rotate relative to each other, thus maintaining the good rigidity of the pressure-relief component and ensuring sufficient load-bearing capacity. Therefore, the pressure-relief component proposed in this application combines the advantages of both traditional rigid and flexible systems, and ensures both load-bearing capacity and resistance to rheological deformation, making it particularly suitable for use in soft rock formations with high ground stress.

[0010] Furthermore, a first positioning element is provided on the inner wall of the end of the first elliptical tube facing the direction of the second elliptical tube, and a second positioning element is provided on the inner wall of the end of the second elliptical tube facing the direction of the first elliptical tube.

[0011] A rotating shaft is fixedly connected to the second positioning component, and a through hole matching the rotating shaft is opened on the first positioning component; the axis of the rotating shaft passes through the center point of the end face of the second elliptical tube.

[0012] This design achieves relative rotation between the first and second elliptical tubes via a rotating shaft. Both the first and second positioning components are matched to the rotating shaft, with one end fixed to the first positioning component and the other end inserted into the through hole. The second elliptical tube, the second positioning component, and the rotating shaft move synchronously; the presence of the two positioning components ensures stable rotation of the rotating shaft. This rotation design is simple in structure, facilitates rapid on-site assembly, and eliminates the need for bearings and other components, offering significant advantages in both production and installation costs. Furthermore, even if the outer wall of the elliptical tube deforms, it can still maintain effective rotational capability.

[0013] Furthermore, those skilled in the art should understand that the center point of the end face of the elliptical tube in this application is the intersection of the major axis and the minor axis of the elliptical shape of the end face.

[0014] Furthermore, a first positioning groove is provided on the end face of the first elliptical tube facing the direction of the second elliptical tube, and a second positioning groove is provided on the end face of the second elliptical tube facing the direction of the first elliptical tube; the first positioning groove is open on the outer wall of the first elliptical tube, and the second positioning groove is open on the outer wall of the second elliptical tube.

[0015] The second positioning slot corresponds one-to-one with the first positioning slot;

[0016] It also includes a connecting component, the two ends of which are respectively connected to a set of opposing first positioning slots and second positioning slots.

[0017] The connecting assembly includes a shear pin, with its two ends connected to a first positioning groove and a second positioning groove, respectively.

[0018] In this design, both the first and second positioning slots are open on the outer wall and end face of their respective elliptical tubes. This facilitates the connection and interlocking of the first and second positioning slots after the two elliptical tubes are aligned, allowing for the insertion of shear pins from the outside in. The two ends of the shear pins are connected to the first and second positioning slots respectively, enabling the connection between the first and second elliptical tubes. When the external load is large and the loads acting on the first and second elliptical tubes differ, and the two elliptical tubes tend to rotate relative to each other, the shear pins must be cut first to allow relative rotation. The use of shear pins further enhances the energy dissipation capacity of the pressure-bearing component.

[0019] Furthermore, the bottom of the first positioning groove and the second positioning groove are respectively provided with a first threaded blind hole and a second threaded blind hole; the shear pin is provided with a first threaded through hole and a second threaded through hole corresponding to the first threaded blind hole and the second threaded blind hole, respectively. In this solution, the two ends of the shear pin are respectively connected to the first positioning groove and the second positioning groove by bolts.

[0020] Furthermore, it also includes a first cover and a second cover, which are respectively installed in the first positioning groove and the second positioning groove, to protect the internal shear pins and prevent them from being sheared during construction operations such as shotcrete.

[0021] Furthermore, the first cover and the second cover are respectively provided with a third threaded through hole and a fourth threaded through hole that match the first threaded through hole and the second threaded through hole; the inner walls of the first cover and the second cover are both provided with arc-shaped grooves that match the shear pin.

[0022] In this installation method, the first and second threaded through holes on the shear pin are aligned with the first and second threaded blind holes, respectively. Then, the first and second covers are installed, aligning the third and fourth threaded through holes with the first and second threaded through holes, respectively. This allows for a secure connection between the first and second covers, the shear pin, and the first and second elliptical tubes using two sets of bolts. This connection method ensures that the shear pin can be properly sheared without interference.

[0023] Furthermore, the minor axis or major axis of the end face of the first elliptical tube extends radially along the tunnel.

[0024] When the minor axis of the end face of the first elliptical tube extends radially along the tunnel, the pressure-relief member of this application is more suitable for installation within the initial support. When the major axis of the end face of the first elliptical tube extends radially along the tunnel, the pressure-relief member of this application is more suitable for installation within the secondary lining.

[0025] Furthermore, it also includes a connecting plate that is fixedly connected to the first elliptical tube, and the connecting plate is parallel to the axis of the first elliptical tube.

[0026] The connecting plate is used to connect with existing components inside the initial support and / or the secondary lining to realize the installation and positioning of the pressure relief component of this application.

[0027] In addition, the connecting plate of this scheme is fixedly connected to the first elliptical tube, but not to the second elliptical tube. The connecting plate is fixed in the initial support or pressure relief concrete layer. When the external concrete is subjected to local deformation, the first elliptical tube fixedly connected to the connecting plate is relatively stable, while the connecting plate is more likely to squeeze the second elliptical tube to make it move, thereby increasing the possibility of the second elliptical tube rotating relative to the first elliptical tube.

[0028] Furthermore, there are two connecting plates; the two connecting plates are parallel to each other and are located at both ends of the major axis of the end face of the first elliptical tube.

[0029] Compared with the prior art, this utility model has at least the following advantages and beneficial effects:

[0030] 1. This utility model provides a pressure-relief device for soft rock tunnel support structures, which can fully bear the later rheological deformation of the tunnel surrounding rock under high ground stress soft rock strata conditions, thereby ensuring the stability and effectiveness of the initial support structure during long-term operation and reducing the risk of damage to the initial support structure.

[0031] 2. This utility model provides a pressure-relief device for soft rock tunnel support structures, which can squeeze the external concrete and thus consume a large amount of energy. This is beneficial for consuming the rheological deformation generated during tunnel operation within the support structure, extending the service life and maintenance cycle of the tunnel. Attached Figure Description

[0032] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0033] Figure 1 This is a cross-sectional view of a specific embodiment of the present utility model;

[0034] Figure 2 This is a schematic diagram of the structure of the first elliptical tube in a specific embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the structure of the second elliptical tube in a specific embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the shear pin structure in a specific embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram showing the separation of the first cover and the second cover in a specific embodiment of this utility model.

[0038] The attached diagram shows the markings and corresponding component names:

[0039] 101-First elliptical tube, 102-Second elliptical tube, 103-First positioning component, 104-Second positioning component, 105-Rotating shaft, 106-Through hole, 107-First positioning groove, 108-Second positioning groove, 109-Shear pin, 110-First threaded blind hole, 111-Second threaded blind hole, 112-First threaded through hole, 113-Second threaded through hole, 114-First cover, 115-Second cover, 116-Third threaded through hole, 117-Fourth threaded through hole, 118-Arc groove, 119-Connecting plate. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model. In the description of this application, it should be understood that terms such as "front," "rear," "left," "right," "up," "down," "vertical," "horizontal," "high," "low," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0041] Example 1:

[0042] like Figures 1 to 5 The pressure relief device shown is used for soft rock tunnel support structure, including a first elliptical tube 101 and a second elliptical tube 102 with their end faces facing each other; the first elliptical tube 101 and the second elliptical tube 102 are rotatably connected, and the axis of rotation passes through the center point of the end face of the first elliptical tube 101 and the center point of the end face of the second elliptical tube 102.

[0043] In this embodiment, the specific rotational connection method between the first elliptical tube 101 and the second elliptical tube 102 is as follows:

[0044] A first positioning element 103 is provided on the inner wall of the end of the first elliptical tube 101 facing the direction of the second elliptical tube 102, and a second positioning element 104 is provided on the inner wall of the end of the second elliptical tube 102 facing the direction of the first elliptical tube 101. A rotating shaft 105 is fixedly connected to the second positioning element 104, and a through hole 106 matching the rotating shaft 105 is formed on the first positioning element 103. The axis of the rotating shaft 105 passes through the center point of the end face of the second elliptical tube 102. The diameter of the through hole 106 is equal to the outer diameter of the rotating shaft 105.

[0045] A first positioning groove 107 is provided on the end face of the first elliptical tube 101 facing the direction of the second elliptical tube 102, and a second positioning groove 108 is provided on the end face of the second elliptical tube 102 facing the direction of the first elliptical tube 101; the first positioning groove 107 is open on the outer wall of the first elliptical tube 101, and the second positioning groove 108 is open on the outer wall of the second elliptical tube 102.

[0046] The second positioning groove 108 corresponds one-to-one with the first positioning groove 107;

[0047] It also includes a shear pin 109, the two ends of which are respectively connected to the first positioning groove 107 and the second positioning groove 108.

[0048] The bottom of the first positioning groove 107 and the second positioning groove 108 are respectively provided with a first threaded blind hole 110 and a second threaded blind hole 111; the shear pin 109 is provided with a first threaded through hole 112 and a second threaded through hole 113 corresponding to the first threaded blind hole 110 and the second threaded blind hole 111, respectively.

[0049] It also includes a first cover 114 and a second cover 115 for installation in the first positioning groove 107 and the second positioning groove 108, respectively; the first cover 114 and the second cover 115 are respectively provided with a third threaded through hole 116 and a fourth threaded through hole 117 that match the first threaded through hole 112 and the second threaded through hole 113; the inner walls of the first cover 114 and the second cover 115 are both provided with arc-shaped grooves 118 that match the shear pin 109.

[0050] In this embodiment, the first elliptical tube 101 and the second elliptical tube 102 have the same shape and size, and their end faces are completely aligned during initial installation. The first positioning member 103 and the second positioning member 104 are both elliptical in shape, matching the internal shape of the first elliptical tube 101 and the second elliptical tube 102 respectively, achieving complete filling at the ends, thereby ensuring that the ends are not easily deformed, which is beneficial to ensuring that the first elliptical tube 101 and the second elliptical tube can rotate relative to each other.

[0051] Preferably, the first elliptical tube 101, the second elliptical tube 102, the first positioning member 103, and the second positioning member 104 are all made of steel. The first positioning member 103 and the second positioning member 104 are respectively welded inside the first elliptical tube 101 and the second elliptical tube 102.

[0052] Preferably, the pressure-relief member 1 further includes a connecting plate 119, which is fixedly connected to the first elliptical tube 101 and is parallel to the axis of the first elliptical tube 101. In this embodiment, the connecting plate 3 is also perpendicular to the major axis of the end face of the first elliptical tube 101.

[0053] In a more preferred embodiment, there are two connecting plates 119, which are parallel to each other and located at both ends of the major axis of the end face of the first elliptical tube 101. When the second elliptical tube 10 is connected to the first elliptical tube 101 by a plurality of shear pins 109, the two ends of the major axis of the end face of the second elliptical tube 10 are in contact with the two connecting plates 119 respectively.

[0054] In a more preferred embodiment, the rotating shaft 105 is tubular, which facilitates the entry of some concrete into the first elliptical tube 101 and the second elliptical tube 102 during spraying to improve compressive strength.

[0055] The installation method of the pressure relief component 1 in this embodiment is as follows:

[0056] Insert the rotating shaft 105 into the through hole 106 so that the end faces of the first elliptical tube 101 and the second elliptical tube 102 abut against each other.

[0057] Adjust the orientation of the first elliptical tube 101 and / or the second elliptical tube 102 so that the end faces of the first elliptical tube 101 and the second elliptical tube 102 are directly opposite each other, that is, the first positioning groove 107 and the second positioning groove 108 are directly opposite each other.

[0058] In each pair of opposing first positioning grooves 107 and second positioning grooves 108: shear pins 109 are installed, with the first threaded through hole 112 and the second threaded through hole 113 on the shear pins 109 aligned with the first threaded blind hole 110 and the second threaded blind hole 111, respectively. Then, the first cover 114 and the second cover 115 are installed into the first positioning groove 107 and the second positioning groove 108, respectively, with the third threaded through hole 116 and the fourth threaded through hole 117 aligned with the first threaded through hole 112 and the second threaded through hole 113, respectively. The first cover, the second cover, the shear pins, and the first and second elliptical tubes are fixedly connected by two sets of bolts; and the connecting plate 119 is welded.

[0059] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Additionally, the term "connection" as used herein, unless otherwise specified, can refer to a direct connection or an indirect connection via other components.

Claims

1. A pressure-relief device for soft rock tunnel support structures, characterized in that, It includes a first elliptical tube (101) and a second elliptical tube (102) with their end faces facing each other; the first elliptical tube (101) and the second elliptical tube (102) are rotatably connected, and the axis of rotation passes through the center point of the end face of the first elliptical tube (101) and the center point of the end face of the second elliptical tube (102).

2. The pressure-relief device for soft rock tunnel support structure according to claim 1, characterized in that, A first positioning element (103) is provided on the inner wall of the end of the first elliptical tube (101) facing the direction of the second elliptical tube (102), and a second positioning element (104) is provided on the inner wall of the end of the second elliptical tube (102) facing the direction of the first elliptical tube (101). The second positioning member (104) is fixedly connected to the rotating shaft (105), and the first positioning member (103) has a through hole (106) that matches the rotating shaft (105); the axis of the rotating shaft (105) passes through the center point of the end face of the second elliptical tube (102).

3. A pressure-relief device for soft rock tunnel support structures according to claim 1, characterized in that, A first positioning groove (107) is provided on the end face of the first elliptical tube (101) facing the direction of the second elliptical tube (102), and a second positioning groove (108) is provided on the end face of the second elliptical tube (102) facing the direction of the first elliptical tube (101); the first positioning groove (107) is open on the outer wall of the first elliptical tube (101), and the second positioning groove (108) is open on the outer wall of the second elliptical tube (102); The second positioning groove (108) corresponds one-to-one with the first positioning groove (107); It also includes a connecting component, the two ends of which are respectively connected to a set of opposite first positioning grooves (107) and second positioning grooves (108).

4. A pressure-relief device for soft rock tunnel support structures according to claim 3, characterized in that, The connecting assembly includes a shear pin (109), the two ends of which are respectively connected to the first positioning groove (107) and the second positioning groove (108).

5. A pressure-relief device for soft rock tunnel support structures according to claim 4, characterized in that, The bottom of the first positioning groove (107) and the second positioning groove (108) are respectively provided with a first threaded blind hole (110) and a second threaded blind hole (111); the shear pin (109) is provided with a first threaded through hole (112) and a second threaded through hole (113) corresponding to the first threaded blind hole (110) and the second threaded blind hole (111) respectively.

6. A pressure-relief device for soft rock tunnel support structures according to claim 5, characterized in that, It also includes a first cover (114) and a second cover (115) for installation in the first positioning groove (107) and the second positioning groove (108), respectively.

7. A pressure-relief device for soft rock tunnel support structures according to claim 6, characterized in that, The first cover (114) and the second cover (115) are respectively provided with a third threaded through hole (116) and a fourth threaded through hole (117) that match the first threaded through hole (112) and the second threaded through hole (113); the inner walls of the first cover (114) and the second cover (115) are provided with an arc-shaped groove (118) that matches the shear pin (109).

8. A pressure-relief device for soft rock tunnel support structures according to claim 1, characterized in that, The short or long axis of the end face of the first elliptical tube (101) extends radially along the tunnel.

9. A pressure-relief device for soft rock tunnel support structures according to claim 1, characterized in that, It also includes a connecting plate (119) fixedly connected to the first elliptical tube (101), and the connecting plate (119) is parallel to the axis of the first elliptical tube (101).

10. A pressure-relief device for soft rock tunnel support structures according to claim 9, characterized in that, There are two connecting plates (119); the two connecting plates (119) are parallel to each other and are located at both ends of the major axis of the end face of the first elliptical tube (101).

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