A tunnel platform-free arch frame and its installation method

Abstract

The present invention belongs to the technical field of tunnel construction support, and specifically discloses a tunnel platform-free arch frame and an installation method thereof, comprising a plurality of groups of curved arch body parts and a plurality of groups of arch frame diagonal braces, each group of curved arch body parts comprising an upper step arch frame and a lower step arch frame, the upper step arch frame comprising a top arch frame N1 located at the middle top, middle arch frames N2 and N3 located at both sides of the top arch frame, and also comprising base arch frames N4 and N5 located at the bottoms of both sides of the middle arch frame, the lower step arch frame comprising supporting arch frames N6 and N7 located at the bottom of the base arch frame, two arch frame diagonal braces are symmetrically arranged on both sides of each group of arch body parts, and the arch frame diagonal braces are respectively arranged on both sides of the base arch frame. The present invention has the advantages of simple structure and fast construction.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel construction support, and in particular relates to a tunnel stand-free arch frame and an installation method thereof. Background Art

[0002] In the process of domestic tunnel construction, when the up and down step method is used for construction, a self-made scaffold is usually used for tunnel arch installation. After the tunnel excavation is completed, the loader is first used to transport the arch to the self-made scaffold, and then the workers assemble the arch on site in sections on the scaffold. When the arch is in place, the horizontal position and elevation of the arch are adjusted manually. With the existing technology, the construction workers stay on the tunnel face without initial support for a long time, and due to the slow construction progress, the initial support cannot be formed quickly, which poses a great safety hazard. In addition, the construction workers assemble on site on the scaffold, with a large number of workers involved, low construction efficiency, long operation time, and increased construction costs. Since the excavation scaffold needs to be frequently moved and pushed out, the safety risk is relatively large and it is not conducive to the operation of large-scale mechanical equipment, such as double-arm rock drilling rigs, wet spraying manipulators, cantilever tunneling machines, etc. Summary of the invention

[0003] The purpose of the present invention is to provide a tunnel arch installation method without a scaffold, which solves the potential safety hazard caused by construction workers staying on the tunnel face for a long time without initial support protection.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a tunnel platform-free arch frame, including multiple groups of curved arch-shaped main bodies and multiple groups of arch frame diagonal braces, each group of curved arch-shaped main bodies includes an upper step arch frame and a lower step arch frame, the upper step arch frame includes a top arch frame N1 located at the middle top, middle arch frames N2 and N3 located on both sides of the top arch frame, and also includes base arch frames N4 and N5 located at the bottom of both sides of the middle arch frame, the lower step arch frame includes supporting arch frames N6 and N7 located at the bottom of the base arch frame, and two arch frame diagonal braces are symmetrically arranged on both sides of each group of arched main bodies, and the arch frame diagonal braces are respectively arranged on both sides of the base arch frame.

[0005] Furthermore, the multiple groups of curved arched body parts are arranged in sequence and spaced apart along the depth direction of the tunnel, and adjacent curved arched body parts are connected by connecting steel plates.

[0006] Furthermore, one end of the arch frame diagonal brace is fixedly connected to the edge of the base arch frame, and the other end extends obliquely downward toward the end of the curved arched main body to support the curved arched main body. The arch frame diagonal brace is obliquely inserted downward and supported on the surrounding wall of the tunnel arch. The arch frame diagonal brace and the base arch frame are connected by a connecting steel plate.

[0007] Furthermore, adjacent arch frames of the curved arched main body are connected by a quick connector, and the quick connector includes two connecting plates located on both sides of the connection between adjacent arch frames, and bolts for fixing the two connecting plates on the arch frames. Long holes are provided at positions on the arch frames corresponding to the connecting plates. The quick connector also includes an adjustment component, and the adjustment component includes connecting ear plates respectively arranged at the bottom of adjacent arch frames, and right-angle bolts connecting the two connecting ear plates. The two ear plates at the bottom of adjacent arch frames are vertically arranged, and both ends of the right-angle bolts respectively pass through the ear plates and are then fastened by nuts.

[0008] A tunnel arch installation method without a scaffold comprises the following steps:

[0009] 1) After the tunnel upper step is excavated and slag is discharged, the on-site spraying of concrete is organized to seal the excavation surface and the first layer of steel mesh is laid at the same time;

[0010] 2) Transport the arch frame to the construction site near the excavation face, and assemble the arch frame by connecting bolts and steel plates through the coordination of the platform vehicle and construction personnel;

[0011] 3) The assembled arch frame is delivered to the predetermined installation position by rotating the telescopic arm of the telescopic working platform;

[0012] 4) After on-site measurement and positioning, install the arch frame diagonal brace according to the design and construction locking anchor rods and longitudinal connecting steel bars, fix the arch frame and complete the installation of the upper step arch frame;

[0013] 5) The lower steps of the tunnel are excavated alternately on the left and right sides. After the excavation is completed, the supporting arch frames N6 and N7 are installed alternately by manual operation;

[0014] 6) Repeat steps 1)-5) until the arch frame in the entire tunnel is installed.

[0015] Furthermore, in the step 2), the arch frames are assembled according to the numbers, the arch frame numbered N1 located in the middle of the top is the top arch frame, the symmetrical positions on the left and right sides are the middle arch frames N2 and N3, and the base arch frames N4 and N5 are located below. During assembly, a rotating telescopic working platform is used to place N1 in the middle of the platform and lift it to a suitable height, then stop lifting and install N2 and N3 on both sides of N1. After the installation is completed, it is lifted to a suitable height again and then N4 and N5 are assembled until the arch frame assembly in the upper step is completed.

[0016] Furthermore, the rotating and telescopic working platform has the function of adjusting in vertical and horizontal directions, and a worker who adjusts the position of the arch is arranged in the operating platform of the rotating and telescopic working platform.

[0017] The present invention has the advantages that:

[0018] 1. Through the implementation of this construction method, the initial support of the tunnel can be completed quickly, the overall force can be achieved, and the safety risk of tunnel construction can be reduced;

[0019] 2. This construction method greatly improves the construction efficiency. According to the commonly used self-made scaffolding, it takes 1 hour to install an arch frame, while this construction method only takes 0.5 hours, and the construction efficiency is doubled;

[0020] 3. The number of laborers involved in this construction method is reduced from 6 to 4, which effectively reduces construction costs and reduces the safety risks of tunnel construction. It does not require special equipment and uses general equipment, with high equipment utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the arch structure of the present invention.

[0022] Figure 2 It is a structural schematic diagram of the quick connector in the arch frame of the present invention.

[0023] 1. Top arch frame; 2. Middle arch frame; 3. Base arch frame; 4. Support arch frame; 5. Arch frame diagonal brace; 6. Quick connector; 61. Connecting piece; 62. Bolt; 63. Ear plate; 64. Right-angle bolt. DETAILED DESCRIPTION

[0024] As shown in the figure, a tunnel platform-free arch frame comprises a plurality of groups of curved arched main bodies and a plurality of groups of arch frame diagonal braces, each group of curved arched main bodies comprises an upper step arch frame and a lower step arch frame, the upper step arch frame comprises a top arch frame 1N1 located at the middle top, middle arch frames 2N2 and N3 located at both sides of the top arch frame 1, and also comprises base arch frames 3N4 and N5 located at the bottoms of both sides of the middle arch frame, the lower step arch frame comprises supporting arch frames 4N6 and N7 located at the bottom of the base arch frame 3, two arch frame diagonal braces 5 are symmetrically arranged on both sides of each group of arched main bodies, and the arch frame diagonal braces 5 are respectively arranged on both sides of the base arch frame 3; the plurality of groups of curved arched main bodies are arranged in sequence at intervals along the depth direction of the tunnel to form an integral tunnel arch frame protection, and adjacent curved arched main bodies are connected by connecting steel plates; one end of the arch frame diagonal brace 5 is fixedly connected to the edge of the base arch frame 3, and the other end is inclined downward toward the end of the curved arched main body. The arch frame extends to support the curved arch body, the arch frame diagonal brace 5 is inserted obliquely downward and supported on the peripheral wall of the tunnel arch, the arch frame diagonal brace 5 and the base arch frame 3 are connected by a connecting steel plate, and the adjacent arch frames of the curved arch body are connected by a quick connector 6, the quick connector 6 includes two connecting pieces 61 located on both sides of the connection between adjacent arch frames, the connecting pieces are located at the vertical rib position in the middle of the arch frame I-beam, and bolts 62 for fixing the two connecting pieces 61 on the arch frame, and long holes are provided at positions corresponding to the connecting pieces 61 on the arch frame, and the quick connector 6 also includes an adjustment component, the adjustment component includes connecting ear plates 63 respectively arranged at the bottom of adjacent arch frames, and right-angle bolts 64 connecting the two connecting ear plates 63, the two ear plates 63 at the bottom of adjacent arch frames are arranged vertically, and the two ends of the right-angle bolt 64 pass through the ear plates 63 respectively and are then fastened by nuts;

[0025] A method for installing an arch frame without a platform in a tunnel comprises the following steps: when the tunnel is constructed by the upper and lower step method, after the upper step is excavated and slag is discharged, on-site spraying of concrete is immediately organized to seal the excavation surface and lay the first layer of steel mesh, and at the same time, the arch frame is transported to a position close to the excavation face at the construction site, and an operator is organized on the ground to first place a top arch frame N1 in the middle position of a platform, and after the platform vehicle is slightly lifted, the middle arch frames N2 and N3 are respectively connected to the top arch frame N1 through quick connectors, and after the connection is completed, the platform vehicle is slightly lifted again, and the base arch frames N4 and N5 are respectively connected to the middle arch frames N2 and N3 through quick connectors, so that the upper step N1 to N5 sections of the arch frame connection is completed, and each section of the steel arch frame is connected by a quick connector, and the steel plates are closely attached to each other, and then the arch frame diagonal braces are installed on both sides of the base arch frames N4 and N5.

[0026] After the closed excavation surface is sprayed with concrete and the steel mesh is installed, the assembled arch frame is lifted upwards through the vertical lifting function of the telescopic arm of the rotating telescopic work platform, and then the arch frame is transported to the predetermined installation position using its horizontal telescopic function. There are two laborers in the operating platform of the rotating telescopic work platform who can adjust the position of the arch frame at any time, and then accurately locate it through on-site measurement, and construct locking anchor rods and longitudinal connecting steel bars according to the design to fix the arch frame and complete the installation of the upper step arch frame.

[0027] The lower step of the tunnel is excavated alternately on the left and right sides. After the excavation of the lower step is completed, the supporting arch frames N6 and N7 are installed alternately by manual means in a timely manner.

[0028] The rotating and telescopic working platform is flexible and maneuverable and can be used for arch installation, mesh installation, anchor installation, climbing operations, etc.

Claims

1. A tunnel arch without a platform, characterized in that: It includes multiple groups of curved arched body parts and multiple groups of arch frame diagonal braces, each group of curved arched body parts includes an upper step arch frame and a lower step arch frame, the upper step arch frame includes a top arch frame N1 located at the middle top, middle arch frames N2 and N3 located on both sides of the top arch frame, and also includes base arch frames N4 and N5 located at the bottom of both sides of the middle arch frame, the lower step arch frame includes supporting arch frames N6 and N7 located at the bottom of the base arch frame, and two arch frame diagonal braces are symmetrically arranged on both sides of each group of arched body parts, and the arch frame diagonal braces are respectively arranged on both sides of the base arch frame; multiple groups of curved arched body parts are arranged in sequence at intervals along the depth direction of the tunnel, and adjacent curved arched body parts are connected by connecting steel plates; one end of the arch frame diagonal brace is fixedly connected to the edge of the base arch frame, and the other end is inclined downward toward the end of the curved arched body part The arch frame extends in the end direction to support the curved arch main body, the arch frame diagonal brace is inserted obliquely downward and supported on the peripheral wall of the tunnel arch, and the arch frame diagonal brace and the base arch frame are connected by a connecting steel plate; adjacent arch frames of the curved arch main body are connected by a quick connector, and the quick connector includes two connecting plates located on both sides of the connection between adjacent arch frames, and bolts for fixing the two connecting plates on the arch frame, and long holes are provided at positions corresponding to the connecting plates on the arch frame, and the quick connector also includes an adjustment component, which includes connecting ear plates respectively arranged at the bottom of adjacent arch frames, and right-angle bolts connecting the two connecting ear plates, and the two ear plates at the bottom of adjacent arch frames are vertically arranged, and the two ends of the right-angle bolt pass through the ear plates respectively and are then fastened by nuts.

2. A method for installing a tunnel arch frame without a scaffold as claimed in claim 1, characterized in that: The following steps are involved: After the tunnel upper step is excavated and slag is discharged, the on-site spraying of concrete is organized to seal the excavation surface and the first layer of steel mesh is laid at the same time; Transport the arch frame to the construction site near the excavation face, and assemble the arch frame by connecting bolts and steel plates through the coordination of the platform vehicle and construction workers; The assembled arch frame is delivered to the predetermined installation position by rotating the telescopic arm of the telescopic working platform; After on-site measurement and positioning, the locking anchor rods and longitudinal connecting steel bars are constructed according to the design, the arch frame is fixed and the upper step arch frame installation is completed; The lower steps of the tunnel are excavated alternately on the left and right sides. After the excavation is completed, the arch frames are installed alternately by manual labor. Repeat steps 1)-5) until the arch frame in the entire tunnel is installed.

3. The tunnel arch installation method without a scaffold as claimed in claim 2, characterized in that: In the step 2), the arch frames are assembled according to the numbers. The arch frame located in the middle of the top is numbered N1, and the symmetrical positions on the left and right sides are N2 and N3 respectively. The arch frames further down are N4 and N5. During assembly, a rotating telescopic working platform is used to place N1 in the middle of the platform and lift it to a suitable height. Then the lifting is stopped and N2 and N3 are installed on both sides of N1. After the installation is completed, it is lifted to a suitable height again and then N4 and N5 are assembled until the arch frame assembly in the upper step is completed.

4. The tunnel arch installation method without a scaffold as claimed in claim 2, characterized in that: The rotating and telescopic working platform has the function of adjusting in vertical and horizontal directions, and a worker for adjusting the position of the arch frame is arranged in the operating platform of the rotating and telescopic working platform.

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