Damped telescopic steel arch

Abstract

The application relates to a damping type telescopic steel arch, which comprises at least one pair of single-arch structures combined to form a steel arch, characterized in that the damping type telescopic steel arch further comprises a channel steel connected with the single-arch structures in a sliding mode along the extension direction of the profile of the single-arch structures and connecting the at least one pair of single-arch structures, a slow-release damping assembly comprising a damping fixed welding gasket fixedly connected to the single-arch structures and a damping sliding gasket fixedly connected to the channel steel, the damping fixed welding gasket and the damping sliding gasket being oppositely arranged and abutting each other, and the side wall of the damping fixed welding gasket abutting the damping sliding gasket being obliquely protruded along the sliding direction of the channel steel, and a guide connecting piece fixedly connected to the channel steel and connected with the single-arch structures in a sliding mode along the sliding direction of the channel steel, the guide connecting piece being configured to abut the damping sliding gasket against the damping fixed welding gasket. The application has the effect of improving stability.

Description

Technical Field

[0001] This application relates to the field of protection for tunnel excavation with large deformation, and in particular to a damped telescopic steel arch. Background Technology

[0002] During the excavation of tunnels with large deformation, steel arch frames are usually used to support the surrounding rock to prevent stress release.

[0003] In existing technologies, I-beams are typically bent into arched steel frames to support the surrounding rock. Alternatively, to facilitate the processing and transportation of the steel arch frames, a scheme is used where two halves of a steel arch frame are connected by flanges and then assembled into a complete steel arch frame.

[0004] Regarding the aforementioned prior art, the inventors believe that the existing steel arch frames, which are directly supported on the surrounding rock, are prone to buckling, instability, and deformation when the surrounding rock converges. This not only requires replacement but also poses safety hazards. Summary of the Invention

[0005] In order to improve the working stability of steel arch frames, this application provides a damped telescopic steel arch frame.

[0006] This application provides a damped, telescopic steel arch frame, which adopts the following technical solution:

[0007] A damped retractable steel arch frame includes at least one pair of single arch structures that, when combined, form a steel arch frame. The frame is characterized by further comprising: a channel steel: slidably connected to the single arch structure along its outline, simultaneously connecting at least one pair of single arch structures; a damping release assembly: including a damping welded pad fixedly connected to the single arch structure and a damping sliding pad fixedly connected to the channel steel, the damping welded pad and the damping sliding pad being disposed opposite each other and abutting against each other, the sidewall of the damping welded pad abutting against the damping sliding pad protruding obliquely along the sliding direction of the channel steel; and a guide connector: fixedly connected to the channel steel and slidably connected to the single arch structure along the sliding direction of the channel steel, the guide connector being configured to abut the damping sliding pad against the damping welded pad.

[0008] By adopting the above technical solution, during tunnel excavation, especially in soft rock tunnels, the steel arch frame needs to withstand high ground stress. Conventional steel arch frames directly abut against the surrounding rock, applying all the rock stress to the frame. The structural rigidity and material stiffness of the steel arch frame resist the high stress, but it is prone to buckling and instability when the surrounding rock converges. In this application, because the two single-arch structures are connected by a sliding channel steel, and a damping mechanism is provided between the channel steel and the single-arch structure, when the surrounding rock releases ground stress, the rock exerts force on the single-arch structure. Under the action of ground stress, the single-arch structure slides relative to the channel steel, meaning the ends connecting the two single-arch structures to the channel steel move closer together, thus releasing the surrounding rock stress. During this process, the damping sliding pad abuts against and slides relative to the damping welded pad. Because the sidewalls of the damping welded pads bulge outwards, the interaction force between the damping welded pads and the damping sliding pads gradually increases during the sliding process of the single arch structure. That is, the friction between the damping welded pads and the damping sliding pads increases. At the same time, the bulging sidewalls of the damping welded pads also hinder the movement of the damping sliding pads. The movement of the damping sliding pads not only has to overcome the gradually increasing friction force, but also has to deform under the gradually increasing interaction to adapt to the damping welded pads. Until the two factors mentioned above become so great that the damping sliding pads can no longer move relative to the damping welded pads, the single arch structure also stops moving and begins to provide stable support to the surrounding rock. This achieves the purpose of yielding to the surrounding rock first and then resisting it, allowing some of the stress in the surrounding rock to be released first, and then the surrounding rock is supported by the steel arch frame. Compared to the overall steel arch frame, the above scheme has a deformation amount, and the overall support strength gradually increases after deformation. Therefore, as the tunnel face advances and the stress at the excavation boundary is released, it provides sufficient support, making the operation more stable and able to withstand greater surrounding rock stress, which greatly reduces the possibility of buckling and instability of the steel arch frame. In addition, the above scheme is also easier to process and transport than the overall steel arch frame.

[0009] Optionally, there are two channel steels, which are respectively located on both sides of the single arch structure.

[0010] By adopting the above technical solution, the two channel steels set on both sides of the single arch structure can further improve the connection strength between the two single arch structures, and at the same time make the two single arch structures more stable during movement, reducing the possibility of deflection caused by horizontal component force during the movement of the single arch structure; in addition, the two channel steels mean two sets of slow-release damping components, which can further improve the ability to withstand the stress of the surrounding rock and reduce the possibility of buckling instability.

[0011] Optionally, the guide connector includes a fastening bolt with a nut threaded onto it.

[0012] By adopting the above technical solution, the bolt and nut have a simple structure, are widely available, are easy to install and maintain, and can achieve the purpose of connecting channel steel and single arch structure.

[0013] Optionally, the channel steel is provided with multiple bolt mounting holes.

[0014] By adopting the above technical solution, multiple bolt mounting holes can provide more installation positions for the guide connectors, and the installation position of the guide connectors can be adjusted according to different working conditions; in addition, multiple guide connectors can be connected on the same channel steel, further improving the connection strength between the two single arch structures and further improving the ability to withstand the stress of the surrounding rock.

[0015] Optionally, the single arch structure is provided with a guide groove, and the guide connection assembly is slidably connected in the guide groove.

[0016] By adopting the above technical solution, the guide groove is designed so that the guide connector can achieve the connection effect while smoothly sliding with the single arch structure or channel steel. The structure is simple and easy to process.

[0017] Optionally, two damping weld pads are arranged as a group, with the two damping weld pads located on both sides of the guide groove and simultaneously abutting against the damping sliding pad.

[0018] By adopting the above technical solution, the two damping welded pads located on both sides of the guide groove will not interfere with the movement of the guide connector; the two damping welded pads working together with the damping sliding pads can make the damping welded pads abut against the damping sliding pads with the largest possible area, increasing the contact area between the damping welded pads and the damping sliding pads, thereby increasing the friction between the damping welded pads and the damping sliding pads, so that the arch frame can withstand greater surrounding rock stress.

[0019] Optionally, there are multiple guide connectors, which are evenly distributed on the channel steel along the sliding direction of the channel steel.

[0020] By adopting the above technical solution, the setting of multiple guide connectors can improve the connection strength between the channel steel and the single arch structure, thereby enabling the arch frame to withstand greater surrounding rock stress.

[0021] Optionally, the damping sliding pad is provided with a clearance groove that matches the guide groove.

[0022] By adopting the above technical solution, the setting of the clearance groove can also prevent the damping sliding pad from interfering with the movement of the guide connector.

[0023] In summary, this application includes at least one of the following beneficial technical effects:

[0024] 1. In this application, since the two single-arch structures are connected by a sliding channel steel, and a damping component is provided between the channel steel and the single-arch structure, when the surrounding rock releases in-situ stress, the surrounding rock exerts force on the single-arch structure. Under the action of in-situ stress, the single-arch structure slides relative to the channel steel, that is, the ends of the two single-arch structures connected to the channel steel move closer to each other, at which point the in-situ stress of the surrounding rock is released. During this process, the damping sliding pad abuts against the damping fixed welding pad and slides relative to the damping fixed welding pad. Since the sidewall of the damping fixed welding pad protrudes outward, as the single-arch structure drives the damping fixed welding pad to slide, the interaction force between the damping fixed welding pad and the damping sliding pad increases, that is, the friction force between the damping fixed welding pad and the damping sliding pad increases until the high in-situ stress released by the surrounding rock reaches equilibrium with this friction force. At this point, the single-arch structure stops moving and begins to provide effective support to the surrounding rock, achieving the purpose of yielding to the surrounding rock first and then resisting it. Compared to the overall steel arch frame, the above scheme is more stable and can withstand greater surrounding rock stress because of the deformation and the gradual increase in overall support strength after deformation, which greatly reduces the possibility of instability after buckling of the steel arch frame. In addition, the above scheme is also easier to process and transport than the overall steel arch frame. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an embodiment.

[0026] Figure 2 This is a schematic diagram of the external structure of the slow-release damping component in the embodiment.

[0027] Figure 3 This is a schematic diagram of the damped telescopic steel arch frame in the embodiment.

[0028] Explanation of reference numerals in the attached drawings: 1. Single arch structure; 11. Guide groove; 2. Channel steel; 21. Bolt mounting hole; 3. Slow-release damping assembly; 31. Damping welded gasket; 32. Damping sliding gasket; 33. Clearance groove; 4. Guide connector; 41. Nut. Detailed Implementation

[0029] The present application will be further described in detail below with reference to the accompanying drawings.

[0030] This application discloses a damped, telescopic steel arch frame, see [link]. Figure 1It includes two single-arch structures, channel steel adapted to the arch frame profile, guide connectors, and damping components. The two single-arch structures form a group with their ends facing each other, forming a steel arch frame structure with a broken middle section. The ends of the single-arch structures are connected to the channel steel via guide connectors. There are two channel steels on the same single-arch structure, located on both sides of the waist plate. One end of these two channel steels is connected to one single-arch structure, and the other end is connected to the end of another single-arch structure in the same group in the same manner. The two single-arch structures and the two channel steels are connected by guide connectors to form a steel arch frame structure with a continuous profile.

[0031] See Figure 1 and Figure 2 The slow-release damping assembly is located between the channel steel and the single-arch structure, and each single-arch structure is equipped with a slow-release damping assembly between itself and the channel steel. The slow-release damping assembly includes a damping welded gasket and a damping sliding gasket. The damping welded gasket is fixed to the side wall of the waist plate of the single-arch structure, and the damping sliding gasket is fixed to the side wall of the waist plate of the channel steel. One side wall of the damping welded gasket abuts against the damping sliding gasket, and this side wall is inclined, meaning that the thickness of the damping welded gasket gradually increases from the top to the bottom of the steel arch frame. The damping sliding gasket is pressed against the inclined side wall of the damping welded gasket by the channel steel connected with a guide connector.

[0032] See Figure 1 and Figure 2 In the damped telescopic steel arch frame disclosed in this application, when supporting surrounding rock, the steel arch frame formed by two single arch structures and channel steel is first placed against the surrounding rock. As the surrounding rock converges, high ground stress is applied to the steel arch frame. Since, when the steel arch frame is installed to its initial state of contact with the surrounding rock, the end of the damping sliding pad facing the single arch structure rests above the end of the damping welded pad facing the other single arch structure, and the thickness of the damping welded pad varies, the area of ​​the damping sliding pad resting on the damping welded pad increases as the single arch structure moves under the influence of high ground stress. Furthermore, because the channel steel is connected to the single arch structure via guide connectors, the interaction force between the damping sliding pad and the damping welded pad continuously increases, making it increasingly difficult for the two single arch structures to move towards each other. In other words, the steel arch frame gradually begins to bear more surrounding rock stress, and the steel arch frame gradually begins to play a supporting role.

[0033] See Figure 1 and Figure 2In other embodiments, to facilitate the secure connection of the damping welded pad and the damping sliding pad together via the guide connector and the channel steel, a bolt is used as the guide connector. The bolt enters from the waist plate of one channel steel and exits from the waist plate of another channel steel, with a nut threaded onto the bolt. To allow the channel steel connected by the bolt and nut to slide normally relative to the single arch structure, a guide groove is formed on the waist plate at the end of the single arch structure. The guide groove is set along the moving direction of the single arch structure, and the bolt, serving as the guide connector, passes through the guide groove. In this way, as the single arch structure moves, the bolt slides relative to the single arch structure within the guide groove. At this time, the bolt, as the guide connector, does not interfere with the movement of the single arch structure, while simultaneously achieving the purpose of securing the damping sliding pad against the damping welded pad.

[0034] See Figure 1 In other embodiments, the guide groove extends inward from the end of one single-arch structure opposite another, forming a closed end. The distance between the thicker end of the damping welded pad and the closed end of the guide groove is less than the length of the damping sliding pad. This arrangement can limit excessive release of ground stress and reduce the possibility of increased ground stress due to the expansion of fracture zones within the rock mass caused by excessive release of ground stress.

[0035] See Figure 1 and Figure 2 In other embodiments, to ensure a more stable connection between the two channel steels by the guide connection assembly, the guide groove is positioned at the midpoint of the height of the waist plate of the single arch structure. Simultaneously, considering the need for the interaction force between the damping welded pad and the damping sliding pad to increase steadily and continuously with the movement of the single arch structure, while also not hindering the movement of the guide connection, the damping welded pads on one side of the waist plate of the single arch structure are arranged in pairs, with each pair positioned above and below the guide groove. This arrangement positions the slow-release damping assembly at the midpoint of the area between the single arch structure and the channel steel, allowing the channel steel and the single arch structure to exert a stable and effective clamping effect on the slow-release damping assembly. Furthermore, as the single arch structure moves, the interaction force between the damping welded pad and the damping sliding pad increases steadily and continuously. This also reduces the possibility of warping on one side of the channel steel due to excessive interaction force between the damping welded pad and the damping sliding pad.

[0036] See Figure 2 and Figure 3In other embodiments, multiple bolt mounting holes are provided on the waist plate of the channel steel for installing bolts as guide connectors. These bolt mounting holes are evenly distributed along the contour of the channel steel. By increasing the number of installation positions for the guide connectors, firstly, it can be applied to more working conditions, making the damped telescopic steel arch frame described in this embodiment more versatile; secondly, by installing bolts as connectors in all these bolt mounting holes, the connection strength between the channel steel and the single arch structure can be further improved.

[0037] See Figure 2 In other embodiments, to achieve a larger contact area between the damping welded pad and the damping sliding pad, the sidewalls where the damping sliding pad and the damping welded pad abut are also inclined. That is, the thickness variation direction of the damping sliding pad is opposite to that of the damping welded pad, forming a structure adapted to the damping welded pad. This arrangement results in a larger contact area between the damping sliding pad and the damping welded pad, increasing the friction between them. This leads to greater resistance during the movement of the single arch structure, and consequently, allows the steel arch frame to withstand greater ground stress.

[0038] See Figure 2 and Figure 3 The damping sliding pad has a clearance groove that matches the guide groove to accommodate the guide connector. The guide groove allows workers to easily install the damping sliding pad at different locations on the channel steel. Without the clearance groove, drilling would be required on-site depending on the presence and location of the guide connector at the installation location, making the process cumbersome.

[0039] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A damped, retractable steel arch frame, comprising at least one pair of single arch structures that combine to form a steel arch frame, characterized in that, Also includes: Channel steel: It slides along the outline of the single arch structure and connects to it, while connecting at least one pair of single arch structures; The slow-release damping assembly includes a damping welded pad fixedly connected to the single arch structure and a damping sliding pad fixedly connected to the channel steel. The damping welded pad and the damping sliding pad are arranged opposite to each other and abut against each other. The side wall of the damping welded pad that abuts against the damping sliding pad protrudes obliquely along the sliding direction of the channel steel. The damping sliding pad is provided with a clearance groove adapted to the guide groove. Guide connector: It is fixedly connected to the channel steel and slides along the sliding direction of the channel steel to connect with the single arch structure. The guide connector is configured to press the damping sliding pad against the damping welded pad. The guide connector includes a fastening bolt with a nut threaded onto it; the channel steel has multiple bolt mounting holes; the single arch structure has a guide groove, and the guide connector is slidably connected to the guide groove; two damping welded pads are arranged as a group, and the two damping welded pads are respectively located on both sides of the guide groove and simultaneously abut against the damping sliding pad. Two single-arch structures form a group and their ends face each other to form a steel arch frame structure that is broken in the middle. The ends of the single-arch structures are connected to channel steel through guide connectors. One end of the two channel steels is connected to one single-arch structure, and the other end is connected to the end of another single-arch structure in the same group in the same way.

2. The damped telescopic steel arch frame according to claim 1, characterized in that: There are two channel steels, which are located on both sides of the single arch structure.

3. The damped telescopic steel arch frame according to claim 1, characterized in that: There are multiple guide connectors, which are evenly distributed on the channel steel along the sliding direction of the channel steel.

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