A foldable tunnel steel arch support structure capable of rapid assembly

Abstract

The application discloses a foldable tunnel steel arch support structure capable of being quickly assembled, which comprises a hydraulic cylinder, a hydraulic control system and a support main body composed of multiple repeated arch support structure units; the support main body can be folded into a 3D structure occupying a very small space in a non-use or transportation state, and can be conveniently and quickly unfolded into a support structure meeting the tunnel support condition in a use state. The application can realize the quick assembling and supporting operation of the tunnel steel arch support structure by using only three hydraulic cylinders, avoids using complex and huge special assembling equipment in the traditional underground tunnel support construction, can effectively improve the tunnel engineering construction efficiency, and realizes the quick recycling and reuse of the tunnel support structure.

Description

Technical Field

[0001] This invention relates to the field of tunnel support, and more particularly to a foldable tunnel steel arch support structure that can be quickly assembled. Background Technology

[0002] With the rapid development of my country's social economy, the number of urban underground tunnel projects has increased rapidly. To effectively control the stress in the surrounding rock during the initial stage of tunnel excavation, appropriately release and control rock deformation, and create a stable and safe working space for subsequent operations, initial tunnel support methods such as shotcrete support are commonly used. However, shotcrete support operations suffer from problems such as harsh working environments, significant material waste, difficulty in quality control, and poor operational timeliness. Replacing shotcrete support with technologies such as precast reinforced (or steel-sectioned) concrete segments, on-site 3D-printed concrete, and steel arch support structures can effectively solve these problems.

[0003] When using prefabricated assembly support structures, structural assembly is a crucial process. A rational and efficient assembly process can fully leverage the strength advantages of prefabricated support structures and improve operational efficiency. In confined underground spaces, due to limited working space, an inside-out assembly process is often employed when using prefabricated assembly support structures. This process involves prefabricating reinforced concrete segments (either steel or shaped steel) in a factory, transporting them by truck to the tunnel construction site, and assembling them on-site using specialized equipment to form a stable support structure. For example, this process is used for the reinforced concrete segments of tunnel boring machines (TBMs). However, this process requires high precision in spatial positioning and structural dimensions, especially for unmarked tunnels with uncertain positioning references, making on-site construction very difficult. Furthermore, the complex and large TBM segment assembly equipment also limits the underground working space to some extent. Japan has also conducted in-depth research on non-shield tunnel prefabrication and assembly technology, forming its own unique prefabrication and assembly technology. For the assembly process from the inside out, it has studied gantry-type assembly equipment and free-moving assembly equipment and formed a special operation method. However, this also inevitably leads to the assembly equipment being too complex and large.

[0004] On-site 3D printing of concrete has been proposed for application in tunnel support operations. This technology fully leverages the achievements of current advanced 3D printing technology to achieve high-precision tunnel support work on-site. However, this technology requires ensuring reliable solidification between material layers during the 3D printing process, while also considering other target parameters such as initial setting time, final setting time, and final setting strength. Furthermore, 3D printed concrete cannot be processed using traditional wet spraying machinery and requires additional specialized equipment on-site.

[0005] Due to the need for integrated assembly of support structures in underground tunnel engineering, special support methods such as steel arch frames, water-expanding anchor bolts, and airbag support have been proposed. However, the current level of integrated equipment is relatively low, and all of these support methods require specialized equipment. For example, the only relatively mature steel arch frame assembly equipment is the three-arm, three-rail steel arch frame assembly trolley, which suffers from low assembly efficiency and high assembly difficulty.

[0006] Based on the above survey results, the following problems exist with existing tunnel support structures:

[0007] (1) Traditional anchor-sprayed support structures have disadvantages such as large material waste and poor operation timeliness, making it difficult to effectively meet the timely support needs of underground tunnels;

[0008] (2) Most other support structures require the construction site to be equipped with special assembly equipment, which not only occupies a large underground working space, but also greatly increases the complexity of construction and affects the overall construction efficiency.

[0009] (3) The existing tunnel steel arch support structure has a low degree of integrated assembly. It is usually assembled in sections on site, which cannot achieve overall assembly. It has disadvantages such as low assembly efficiency and high assembly difficulty. Summary of the Invention

[0010] Based on the shortcomings of existing tunnel support technologies, this invention provides a foldable tunnel steel arch support structure that can be quickly assembled. This tunnel steel arch support structure can provide rapid assembly support in the early stages of tunnel excavation without the need for complex and bulky assembly equipment, thus effectively improving the construction efficiency of underground tunnel projects.

[0011] The objective of this invention is achieved through the following technical solution:

[0012] A foldable tunnel steel arch support structure that can be quickly assembled includes a hydraulic cylinder, a hydraulic control system, and a support body composed of multiple repeating arch structure units.

[0013] Each arch frame structural unit is a bilaterally symmetrical structure, comprising eight support rods and four composite ball hinges. Four support rods are located on the left side, and the other four on the right side. One end of each of the four support rods on the left side is simultaneously and tactilely connected to a composite ball hinge located on the ground, with the other ends of two of the support rods in contact with the ground. One end of each of the four support rods on the right side is simultaneously and tactilely connected to another composite ball hinge located on the ground, with the other ends of two of the support rods in contact with the ground. The other end of one of the remaining support rods on the left side and the other end of one of the remaining support rods on the right side are tactilely connected to a third composite ball hinge. The other end of the last remaining support rod on the left side and the other end of the last remaining support rod on the right side are tactilely connected to a fourth composite ball hinge.

[0014] Each composite ball hinge can roll to connect four support rods; adjacent arch frame structural units share a composite ball hinge located at the top.

[0015] There are three hydraulic cylinders. The piston rods of the three hydraulic cylinders are respectively fixed to the left and right composite ball hinges and the top composite ball hinge away from the hydraulic cylinder of the outermost arch frame structure unit. The hydraulic control system realizes the synchronous movement of the three composite ball hinges of the outermost arch frame structure unit, so that multiple repeating arch frame structure units can be unfolded or folded in sequence.

[0016] Furthermore, the support rod includes a support rod segment and a hemisphere fixed to the support rod segment and hinged to the composite ball hinge.

[0017] Furthermore, the composite ball hinge has a cubic configuration and ball pits on all four sides. The connection between the support rod and the composite ball hinge is achieved by embedding the hemisphere of the support rod into the ball pit.

[0018] Furthermore, the left and right ends of the support rods of the innermost arch frame structure unit closest to the hydraulic cylinder, which are in contact with the ground, are also rolledly connected to a steel pipe rolling constraint device. The steel pipe rolling constraint device is used to fix it to the ground, thereby restricting the movement of the support rod connected to it along the movement direction of the piston rod of the hydraulic cylinder.

[0019] Furthermore, the hydraulic control system includes three three-position four-way directional valves, a pump and an oil tank, and six hydraulic locks. The pump and oil tank are connected in parallel to the three three-position four-way directional valves, and each three-position four-way directional valve is connected to the rod chamber and rodless chamber of a hydraulic cylinder through two hydraulic locks, respectively. The pump and oil tank provide pressurized oil to the three hydraulic cylinders. The three-position four-way directional valves control the direction of oil flow by changing the relative position between the valve core and the valve body, thus opening or closing the oil circuit and changing the working state of the three hydraulic cylinders. The hydraulic locks are used to fix the position of the hydraulic cylinders, so that the tunnel steel arch support structure can be fixed at the designated position when folded or unfolded.

[0020] Furthermore, the support rod is selected from any one of steel pipe, I-beam, channel steel and corrugated steel.

[0021] The beneficial effects of this invention are as follows:

[0022] (1) In view of the problems of low assembly efficiency and non-reusability of traditional tunnel support, the present invention designs a foldable tunnel steel arch support structure that can be quickly assembled. The device adopts a foldable structure based on origami technology. When it is not in use or in the transportation state, it can be folded into a 3D structure that occupies only a small space. When it is in use, it can be easily and quickly unfolded into a support structure that meets the tunnel support conditions.

[0023] (2) The foldable tunnel steel arch support structure of the present invention, which can be quickly assembled, can be mass-produced in a prefabrication plant and can be efficiently transported to the tunnel construction site by truck, which greatly improves the construction efficiency of tunnel engineering; at the same time, the tunnel steel arch support structure can realize the rapid recycling and reuse of tunnel support structure.

[0024] (3) Since the present invention is a novel tunnel steel arch support structure based on origami technology, and the excellent performance of the origami structure is formed by its structure due to the folding behavior, it is unrelated to the material itself. Therefore, the folding structure material used in the present invention can be selected from any high-strength material among steel pipe, I-beam, channel steel and corrugated steel, which greatly broadens the material selection of the tunnel steel arch support structure and makes the tunnel steel arch support structure have a wider range of application scenarios. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the foldable tunnel steel arch support structure that can be quickly assembled according to this embodiment.

[0026] Figure 2 This is a schematic diagram of the support rod.

[0027] Figure 3 This is a detailed schematic diagram of the composite ball hinge used to connect the steel pipe and the connection between the hydraulic cylinders in this embodiment.

[0028] Figure 4 This is a schematic diagram illustrating the working principle of the hydraulic control system in this embodiment.

[0029] Figure 5 This is a schematic diagram of the rolling restraint device for the two steel pipes closest to the wall in this embodiment.

[0030] Figure 6 This is a flowchart illustrating the manufacturing method of the foldable tunnel steel arch support structure that enables rapid assembly, as described in this embodiment.

[0031] In the diagram, the components are: steel pipe 1, support rod section 1-1, hemisphere 1-2, composite ball hinge 2, threaded rod 2-1, nut 2-2, hydraulic cylinder 3, hydraulic control system 4, three-position four-way directional valve 4-1 (pressure port P, return port T, and ports A and B leading to both ends of hydraulic cylinder 3), pump and oil tank 4-2, hydraulic lock 4-3, and steel pipe rolling restraint device 5. Detailed Implementation

[0032] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. The purpose and effects of the present invention will become clearer. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0033] like Figure 1 As shown, the foldable tunnel steel arch support structure of the present invention, which can be quickly assembled, includes a hydraulic cylinder 3, a hydraulic control system 4, and a support body composed of multiple repeating arch structure units.

[0034] The support structure is a three-dimensional structure consisting of multiple repeating arch frame structural units extending along the tunnel axis. Each arch frame structural unit is symmetrical, comprising eight support rods 1 and four composite ball hinges 2. Four support rods 1 are located on the left side, and the other four support rods 1 are located on the right side. One end of each of the four support rods 1 on the left side is simultaneously and rollingly connected to a composite ball hinge 2 located on the ground, with the other ends of two of the support rods 1 in contact with the ground. One end of each of the four support rods 1 on the right side is simultaneously and rollingly connected to another composite ball hinge 2 located on the ground, with the other ends of two of the support rods 1 in contact with the ground. The other end of one of the remaining support rods 1 on the left side and the other end of one of the remaining support rods 1 on the right side are jointly and rollingly connected to a third composite ball hinge 2. The other end of the last remaining support rod 1 on the left side and the other end of the last remaining support rod 1 on the right side are jointly and rollingly connected to a fourth composite ball hinge 2.

[0035] Each composite ball hinge 2 can roll to connect four support rods 1; adjacent arch frame structural units share a composite ball hinge 2 located at the top.

[0036] The spatial position of the composite ball hinge 2 in an arch frame structure unit is related to the real-time deployment position of the tunnel steel arch frame support structure; this arch frame structure unit is repeated along the tunnel axial direction, and the connection is constrained by the composite ball hinge 2 rolling connection; at the bottom of the two support rods 1 closest to the wall, there is a steel pipe rolling constraint device 5, which is connected to the ground in a rolling connection constraint manner, so that when the tunnel steel arch frame support structure is deployed, the positions of these two support rods do not move synchronously along the axial direction.

[0037] There are three hydraulic cylinders 3. The piston rods of the three hydraulic cylinders 3 are respectively fixed to the left and right composite ball hinges and the top composite ball hinge 2 located away from the hydraulic cylinders in the outermost arch frame structural unit. The fixed connection is achieved by threaded rod 2-1 and nut 2-2. One end of threaded rod 2-1 is fixed to the bottom surface of composite ball hinge 2, and the piston rod of hydraulic cylinder 3 is sleeved on threaded rod 2-1 and fixed by nut 2-2. The hydraulic control system 4 realizes the synchronous movement of the three composite ball hinges in the outermost arch frame structural unit, so that multiple repeating arch frame structural units can be unfolded or folded in sequence.

[0038] like Figure 2 As shown, the support rod 1 includes a support rod segment 1-1 and a hemisphere 1-2 fixed to the support rod segment 1-1 and hinged to a composite ball hinge.

[0039] like Figure 3 As shown, the composite ball hinge 2 has a cubic configuration with ball-shaped recesses on all four sides. The radius of each ball-shaped recess is slightly larger than the radius of the hemisphere 1-2 of the support rod 1. The support rod 1 is connected to the composite ball hinge 2 by embedding the hemisphere 1-2 of the support rod 1 into the ball-shaped recess, thus achieving a rolling connection constraint between the four adjacent support rods 1. A threaded rod 2-1 with external threads is also connected to the lower surface of the outermost composite ball hinge 2 for connecting the hydraulic cylinder 3.

[0040] like Figure 4 As shown, the hydraulic control system 4 includes: three three-position four-way directional valves 4-1, one pump and oil tank 4-2, and six hydraulic locks 4-3. The pump and oil tank 4-2 are connected in parallel to the three three-position four-way directional valves 4-1. Each three-position four-way directional valve 4-1 is connected to the rod chamber and rodless chamber of a hydraulic cylinder 3 respectively through two hydraulic locks 4-3. The pump and oil tank 4-2 simultaneously provides pressurized oil to the three hydraulic cylinders 3 through the three three-position four-way directional valves 4-1. The three-position four-way directional valves 4-1 control the direction of oil flow by changing the relative position between the valve core and the valve body, thus opening or closing the oil circuit and changing the working state of the three hydraulic cylinders 3. The hydraulic locks 4-3 are used to fix the position of the hydraulic cylinders 3, so that the tunnel steel arch support structure can be fixed at the designated position when folded or unfolded.

[0041] like Figure 4As shown, each three-position four-way directional valve 4-1 includes three working positions (valve core in the middle and at the left and right ends) and four passage ports (pressure oil port P, return oil port T, and oil ports A and B leading to both ends of hydraulic cylinder 3). When the valve core is in the middle position, the oil inlet P is closed, and the two chambers A and B of the hydraulic cylinder 3 are connected to the return oil port T, causing the piston to float in the hydraulic cylinder 3. When the valve core is in the right position, pressurized oil enters the valve body from port P, flows to the hydraulic cylinder 3 through port A, and the oil flowing back from the hydraulic cylinder 3 enters the valve body through port B and flows back to the oil tank 4-2 through the return oil port T, thus realizing the extension movement of the piston rod of the hydraulic cylinder 3 away from the wall under the action of pressurized oil, thereby realizing the unfolding action of the tunnel steel arch support structure. When the valve core is in the left position, pressurized oil flows to the hydraulic cylinder 3 through ports P and B, and the return oil flows back to the oil tank 4-2 through ports A and T, thus realizing the contraction movement of the piston rod of the hydraulic cylinder 3 towards the wall under the action of pressurized oil, thereby realizing the folding action of the tunnel steel arch support structure.

[0042] like Figure 5 As shown, in order to enable the tunnel steel arch support structure to be deployed, the innermost arch structure unit located in the hydraulic cylinder is restricted from moving along the direction of movement of the piston rod of the hydraulic cylinder. At the end of the support rod 1 on the left and the support rod 1 on the right of the innermost arch structure unit closest to the hydraulic cylinder 3, a steel pipe rolling constraint device 5 is also rolledly connected to the ground. The steel pipe rolling constraint device 5 is fixed on the ground, thereby restricting the movement of the support rod 1 connected to it along the direction of movement of the piston rod of the hydraulic cylinder 3.

[0043] The support rod 1 given in this embodiment is a steel pipe, but any one of I-beams, channel steel, and corrugated steel can also be selected according to the actual situation.

[0044] like Figure 6 As shown, the manufacturing process of the foldable tunnel steel arch support structure that can be quickly assembled according to an embodiment of the present invention includes the following steps:

[0045] Step 1: Select the tunnel steel arch support structure material according to the actual needs of the project, such as steel pipe 1, etc.

[0046] Step 2: Arrange the steel pipes 1 according to the configuration design scheme of the tunnel steel arch support structure. Use composite ball hinges 2 at the nodes to connect the steel pipes 1, so as to achieve rolling connection constraint at the four adjacent steel pipes 1.

[0047] Step 3: The tunnel steel arch support structure can be prefabricated in the factory and can be folded into a 3D structure that occupies only a small space when it is not in use or during transportation.

[0048] Step 4: Use a truck to transport the folded tunnel steel arch support structure to the tunnel construction site, connect three hydraulic cylinders 3 at the designated location, and control the working state of the three hydraulic cylinders 3 through the hydraulic control system 4 to realize the unfolding action of the tunnel steel arch support structure.

[0049] Step 5: When the tunnel steel arch support structure is deployed to the designated position, use hydraulic lock 5 to fix the position of hydraulic cylinder 3, so that the tunnel steel arch support structure is stable in the designated position, and the support operation of the underground tunnel project is realized.

[0050] It will be understood by those skilled in the art that the above descriptions are merely preferred examples of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A foldable tunnel steel arch support structure capable of rapid assembly, characterized in that, It includes hydraulic cylinders, a hydraulic control system, and a support structure consisting of multiple repeating arch frame structural units; Each arch frame structural unit is a bilaterally symmetrical structure, comprising eight support rods and four composite ball hinges. Four support rods are located on the left side, and the other four on the right side. One end of each of the four support rods on the left side is simultaneously and tactilely connected to a composite ball hinge located on the ground, with the other ends of two of the support rods in contact with the ground. One end of each of the four support rods on the right side is simultaneously and tactilely connected to another composite ball hinge located on the ground, with the other ends of two of the support rods in contact with the ground. The other end of one of the remaining support rods on the left side and the other end of one of the remaining support rods on the right side are tactilely connected to a third composite ball hinge. The other end of the last remaining support rod on the left side and the other end of the last remaining support rod on the right side are tactilely connected to a fourth composite ball hinge. Each composite ball hinge can roll to connect four support rods; adjacent arch frame structural units share a composite ball hinge located at the top. There are three hydraulic cylinders. The piston rods of the three hydraulic cylinders are respectively fixed to the left and right composite ball hinges and the top composite ball hinge away from the hydraulic cylinder of the outermost arch frame structure unit. The hydraulic control system realizes the synchronous movement of the three composite ball hinges of the outermost arch frame structure unit, so that multiple repeating arch frame structure units can be unfolded or folded in sequence. The left and right ends of the support rods of the innermost arch frame structure unit closest to the hydraulic cylinder are also connected to a rolling steel pipe constraint device, and the rolling steel pipe constraint device is fixed to the ground, thereby restricting the movement of the support rod connected to it along the movement direction of the piston rod of the hydraulic cylinder. The hydraulic control system includes three three-position four-way directional valves, a pump and an oil tank, and six hydraulic locks. The pump and oil tank are connected in parallel to the three three-position four-way directional valves. Each three-position four-way directional valve is connected to the rod chamber and rodless chamber of a hydraulic cylinder through two hydraulic locks, respectively. The pump and oil tank provide pressurized oil to the three hydraulic cylinders. The three-position four-way directional valves control the direction of oil flow by changing the relative position between the valve core and the valve body, thus opening or closing the oil circuit and changing the working state of the three hydraulic cylinders. The hydraulic locks are used to fix the position of the hydraulic cylinders, so that the tunnel steel arch support structure can be fixed at a designated position when folded or unfolded.

2. The foldable tunnel steel arch support structure capable of rapid assembly according to claim 1, characterized in that, The support rod includes a support rod segment and a hemisphere fixed to the support rod segment and hinged to the composite ball hinge.

3. The foldable tunnel steel arch support structure capable of rapid assembly according to claim 2, characterized in that, The composite ball hinge has a cubic shape and ball pits on all four sides. The support rod is connected to the composite ball hinge by embedding the hemisphere of the support rod into the ball pit.

4. The foldable tunnel steel arch support structure capable of rapid assembly according to claim 1, characterized in that, The support rod is selected from any one of steel pipe, I-beam, channel steel and corrugated steel.

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