Comprehensive stand erecting method for tunnel primary support stand

Abstract

The invention discloses a comprehensive erecting method for a tunnel primary support erecting frame, which comprises the following steps of: respectively mounting channels on two symmetrical longitudinal beams on two sides of a center line in the depth direction of a tunnel excavation trolley, matching the channels with jacks which slide back and forth, movably connecting a bracket above the top of each jack, and arranging two jacks which are adjacent left and right as a group, no less than two groups of jacks are matched in the two channels in a front-back sliding manner; in the tunnel deslagging stage, the excavation trolley is placed on a supported tunnel section, and an integral arch frame is correspondingly erected in the two supporting grooves in the same set of jacks and is clamped and fixed; after tunnel slag discharging and danger discharging are completed, the excavation trolley is moved backwards to the tunnel face, and the front-back distance of the arch frame is adjusted by sliding the jacks; and the jack is started to jack the arch frame, the side wall arch frame is mechanically connected, and clamping and fixing of the arch frame are relieved. The problems that an existing manual stand is long in consumed time and high in cost, the quality is difficult to control, and a stand of a fully-mechanized stand trolley is poor in adaptability are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel construction engineering, and in particular relates to a comprehensive erection method for an initial support frame of a tunnel. Background Art

[0002] The construction process of road tunnels mainly includes tunnel planning, surveying, design, penetration control measurement and construction. In the process of building reinforced concrete structures, primary support is an indispensable link. It can support the formwork and steel bars and provide a solid foundation for concrete construction. At the same time, primary support can also improve the overall stability and safety of the structure and prevent safety accidents such as collapse and landslides during construction.

[0003] At present, the initial support frame of the tunnel is generally set up manually or by a fully mechanized frame trolley. The problems with manual support frame are: 1) It takes a long time. The frame construction can only start after the slag is discharged and the danger is eliminated. The workers work in the tunnel for a long time, which poses a greater safety risk; 2) Due to manpower reasons, the top arch frame cannot be processed as a whole, but must be processed in sections and bolted on site, wasting connecting plates and bolts; 3) It is difficult for workers to adjust the arch frame spacing, and the quality is difficult to control. The problems with fully mechanized frame trolley support frame are: 1) It has high requirements for the work site, and the tunnel width must be much larger than the width of the frame trolley; 2) It has high requirements for tunnel entry, and the entrance slope is steep and inconvenient to enter. Summary of the invention

[0004] The purpose of the present invention is to provide a comprehensive erection method for initial tunnel support, which solves the problems of existing manual erection, such as long time consumption, high cost, difficult quality control, and poor adaptability of fully mechanized erection trolley erection.

[0005] The technical solution adopted by the present invention is: a comprehensive erection method for a tunnel initial support frame, comprising the following steps: Step 1: Install grooves on two symmetrical longitudinal beams on both sides of the center line of the tunnel excavation trolley in the depth direction, and each groove is equipped with a jack that slides forward and backward. A bracket is movably connected above the top of each jack. Two adjacent jacks on the left and right form a group. There are no less than two groups of jacks that slide forward and backward in the two grooves. Step 2: During the tunnel slag discharge stage, the excavation trolley is placed on the supported tunnel section, and an integral arch frame is set up and clamped in the two brackets on the same group of jacks; Step 3: After the tunnel is deslagging and dangerous, move the excavation trolley backward to the tunnel face, and slide each set of jacks to adjust the front and rear distance of the arch frame to the design requirements; Step 4: Start the jack to lift the arch frame to the designed vertical position, mechanically connect the side wall arch frame, release the clamping of the arch frame, and retract the jack.

[0006] The present invention is also characterized in that: The jacks in the same group adjacent to each other on the left and right are connected with synchronization rods.

[0007] Positioning rods with the same length are connected between two adjacent groups of jacks in the same groove.

[0008] Step 2 is specifically as follows: during the tunnel slag discharge stage, the excavation trolley is placed in the supported tunnel section, and the supporting points are marked at symmetrical positions on both sides of the arch frame centerline according to the spacing between the two longitudinal beams of the excavation trolley. Then, an integral arch frame is erected in the two brackets on the same group of jacks, and the two supporting points are located in the two brackets. The fastening bolts are screwed into the vertical plates of the brackets to clamp and fix the arch frame front and back.

[0009] The jack is a hydraulic jack, and the range of the hydraulic jack is greater than the height from the top of the excavation trolley to the designed excavation surface.

[0010] The beneficial effects of the present invention are as follows: the comprehensive erection method for the initial support of the tunnel of the present invention, the preliminary work of the erection is completed in the supported area while the slag is discharged and the danger is eliminated, the trolley is moved to the erection area and the design parameters are adjusted, and the arch frame is installed as a whole by the jack, which reduces the workers' stay time in the erection area, reduces the safety risk, and greatly reduces the erection time and shortens the construction period; and the integrity of the arch frame reduces the use of connecting plates between arch frames, saving materials, and due to semi-mechanization, less manpower is required, reducing human investment; the integrity of the arch frame also avoids the stress concentration of the arch frame caused by improper arch frame connection, and the arch frame spacing can be strictly controlled in combination with the groove, so as to facilitate quality control. In addition, compared with the fully mechanized erection trolley erection, the present invention is not affected by geographical conditions and tunnel width, has low requirements on the construction site, can be directly installed on the excavation trolley, and has good adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of a top view of the present invention when used for initial support frame erection in a tunnel; Figure 2 It is a side view schematic diagram of the hydraulic jack used for the initial support frame of a tunnel according to the present invention.

[0012] In the figure, 1. excavation trolley, 2. longitudinal beam, 3. heading face, 4. channel, 5. hydraulic jack, 6. bracket, 7. fastening bolt, 8. synchronization rod, 9. positioning rod. DETAILED DESCRIPTION

[0013] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0014] Example 1 The present invention provides a comprehensive erection method for initial tunnel support, such as Figure 1and Figure 2 As shown, the following steps are included: Step 1, grooves 4 are respectively installed on the left and right longitudinal beams 2 symmetrically on both sides of the midline of the tunnel excavation trolley 1 in the depth direction, close to one end of the heading face 3, and a hydraulic jack 5 that slides forward and backward is matched in each groove 4. The hydraulic jack 5 and the groove 4 can be matched through a sliding pair with built-in damping, that is, a fixed slide rail is in the groove 4, and a sliding block is slidably engaged on the slide rail, and then the hydraulic jack 5 is fixed above the sliding block. The range of the hydraulic jack 5 is greater than the height from the top of the excavation trolley 1 to the designed excavation surface. A horizontally rotatable bracket 6 is hingedly connected above the top of each hydraulic jack 5. Two hydraulic jacks 5 adjacent to each other at the same front and rear position are a group. In order to ensure the synchronization of the two hydraulic jacks 5 in the same group, a synchronization rod 8 can also be installed between the two. The two groups of hydraulic jacks 5 slide forward and backward in the two grooves 4.

[0015] Step 2: During the tunnel slag discharge stage, the excavation trolley 1 is placed in the supported tunnel section. The surveyor marks the supporting points at symmetrical positions on both sides of the arch frame centerline according to the spacing between the two longitudinal beams 2 of the excavation trolley 1. Then, an integral arch frame is correspondingly erected in the two brackets 6 on the same group of hydraulic jacks 5, and the two supporting points are located in the two brackets 6. Marking the supporting points can prevent the left and right heights from being inconsistent when the integral arch frame is erected in the brackets 6, causing deviation. Then, the fastening bolts 7 are screwed into the vertical plates of the brackets 6 to clamp the vertical surfaces of the arch frame I-beams in front and back.

[0016] Step 3, after the tunnel slag removal and danger removal are completed, the excavation trolley 1 is moved backward to the heading face 3, and each group of hydraulic jacks 5 are slid to adjust the front and rear spacing of the arch frames to the design requirements. If the arch frame spacing design requires equal spacing, the front and rear adjacent groups of jacks in the same channel 4 can also be connected with positioning rods 9 of the same length, for example 1m. In this way, there is no need to adjust the spacing between the two arch frames to be jacked each time. When the excavation trolley 1 is moved backward, it is only necessary to adjust the spacing between the front one of the two arch frames and the last arch frame in the supported area. The front and rear position of the last arch frame in the supported area can be equivalent to the top of the excavation trolley 1 through vertical rods, so that the equal spacing of the overall arch frames can be completed.

[0017] Step 4: Start the hydraulic jack 5 to lift the arch frame to the designed vertical position, mechanically connect the side wall arch frame, release the clamping fixation of the arch frame, and retract the hydraulic jack 5.

[0018] Example 2 The present invention provides a comprehensive erection method for a tunnel initial support frame, comprising the following steps: Step 1, grooves 4 are respectively installed on the left and right longitudinal beams 2 symmetrically on both sides of the midline of the tunnel excavation trolley 1 in the depth direction, close to one end of the heading face 3, and a hydraulic jack 5 that slides forward and backward is matched in each groove 4. The hydraulic jack 5 and the groove 4 can be matched through a sliding pair with built-in damping, that is, a fixed slide rail is in the groove 4, and a sliding block is slidably engaged on the slide rail, and then the hydraulic jack 5 is fixed above the sliding block. The range of the hydraulic jack 5 is greater than the height from the top of the excavation trolley 1 to the designed excavation surface. A horizontally rotatable bracket 6 is hingedly connected above the top of each hydraulic jack 5. Two hydraulic jacks 5 adjacent to each other at the same front and rear position are a group. In order to ensure the synchronization of the two hydraulic jacks 5 in the same group, a synchronization rod 8 can also be installed between the two. Three groups of hydraulic jacks 5 slide forward and backward in the two grooves 4.

[0019] Step 2: During the tunnel slag discharge stage, the excavation trolley 1 is placed in the supported tunnel section. The surveyor marks the supporting points at symmetrical positions on both sides of the arch frame centerline according to the spacing between the two longitudinal beams 2 of the excavation trolley 1. Then, an integral arch frame is correspondingly erected in the two brackets 6 on the same group of hydraulic jacks 5, and the two supporting points are located in the two brackets 6. Marking the supporting points can prevent the left and right heights from being inconsistent when the integral arch frame is erected in the brackets 6, causing deviation. Then, the fastening bolts 7 are screwed into the vertical plates of the brackets 6 to clamp the vertical surfaces of the arch frame I-beams in front and back.

[0020] Step 3, after the tunnel slag removal and danger removal are completed, the excavation trolley 1 is moved backward to the heading face 3, and each group of hydraulic jacks 5 are slid to adjust the front and rear spacing of the arch frames to the design requirements. If the arch frame spacing design requires equal spacing, the front and rear adjacent groups of jacks in the same channel 4 can also be connected with positioning rods 9 of the same length, for example 1m. In this way, there is no need to adjust the spacing between the two arch frames to be jacked each time. When the excavation trolley 1 is moved backward, it is only necessary to adjust the spacing between the frontmost of the three arch frames and the last arch frame in the supported area. The front and rear position of the last arch frame in the supported area can be equivalent to the top of the excavation trolley 1 through vertical rods, so as to complete the equal spacing of the overall arch frames.

[0021] Step 4: Start the hydraulic jack 5 to lift the arch frame to the designed vertical position, mechanically connect the side wall arch frame, release the clamping fixation of the arch frame, and retract the hydraulic jack 5.

[0022] Example 3 The present invention provides a comprehensive erection method for a tunnel initial support frame, comprising the following steps: Step 1, grooves 4 are respectively installed on the left and right longitudinal beams 2 symmetrically on both sides of the midline of the tunnel excavation trolley 1 in the depth direction, close to one end of the heading face 3, and a hydraulic jack 5 that slides forward and backward is matched in each groove 4. The hydraulic jack 5 and the groove 4 can be matched through a sliding pair with built-in damping, that is, a fixed slide rail is in the groove 4, and a sliding block is slidably engaged on the slide rail, and then the hydraulic jack 5 is fixed above the sliding block. The range of the hydraulic jack 5 is greater than the height from the top of the excavation trolley 1 to the designed excavation surface. A horizontally rotatable bracket 6 is hingedly connected above the top of each hydraulic jack 5. Two hydraulic jacks 5 adjacent to each other at the same front and rear position are a group. In order to ensure the synchronization of the two hydraulic jacks 5 in the same group, a synchronization rod 8 can also be installed between the two. Four groups of hydraulic jacks 5 slide forward and backward in the two grooves 4.

[0023] Step 2: During the tunnel slag discharge stage, the excavation trolley 1 is placed in the supported tunnel section. The surveyor marks the supporting points at symmetrical positions on both sides of the arch frame centerline according to the spacing between the two longitudinal beams 2 of the excavation trolley 1. Then, an integral arch frame is correspondingly erected in the two brackets 6 on the same group of hydraulic jacks 5, and the two supporting points are located in the two brackets 6. Marking the supporting points can prevent the left and right heights from being inconsistent when the integral arch frame is erected in the brackets 6, causing deviation. Then, the fastening bolts 7 are screwed into the vertical plates of the brackets 6 to clamp the vertical surfaces of the arch frame I-beams in front and back.

[0024] Step 3, after the tunnel slag removal and danger removal are completed, the excavation trolley 1 is moved backward to the heading face 3, and each group of hydraulic jacks 5 are slid to adjust the front and rear spacing of the arch frames to the design requirements. If the arch frame spacing design requires equal spacing, the front and rear adjacent groups of jacks in the same channel 4 can also be connected with positioning rods 9 of the same length, for example 1m. In this way, there is no need to adjust the spacing between the two arch frames to be jacked each time. When the excavation trolley 1 is moved backward, it is only necessary to adjust the spacing between the frontmost of the four arch frames and the last arch frame in the supported area. The front and rear position of the last arch frame in the supported area can be equivalent to the top of the excavation trolley 1 through vertical rods, so that the equal spacing of the overall arch frames can be completed.

[0025] Step 4: Start the hydraulic jack 5 to lift the arch frame to the designed vertical position, mechanically connect the side wall arch frame, release the clamping fixation of the arch frame, and retract the hydraulic jack 5.

Claims

1. A comprehensive erection method for initial tunnel support, characterized in that: The following steps are involved: Step 1: Install grooves on two symmetrical longitudinal beams on both sides of the center line of the tunnel excavation trolley in the depth direction, and each groove is equipped with a jack that slides forward and backward. A bracket is movably connected above the top of each jack. Two adjacent jacks on the left and right form a group. There are no less than two groups of jacks that slide forward and backward in the two grooves. Step 2: During the tunnel slag discharge stage, the excavation trolley is placed on the supported tunnel section, and an integral arch frame is set up and clamped in the two brackets on the same group of jacks; Step 3: After the tunnel is deslagging and dangerous, move the excavation trolley backward to the tunnel face, and slide each set of jacks to adjust the front and rear distance of the arch frame to the design requirements; Step 4: Start the jack to lift the arch frame to the designed vertical position, mechanically connect the side wall arch frame, release the clamping of the arch frame, and retract the jack.

2. The comprehensive erection method for initial tunnel support according to claim 1, characterized in that: The jacks in the same group adjacent to each other on the left and right are connected with synchronization rods.

3. The comprehensive erection method for initial tunnel support according to claim 2, characterized in that: Positioning rods with the same length are connected between two adjacent groups of jacks in the same groove.

4. The comprehensive erection method for initial tunnel support according to claim 1, characterized in that: The step 2 is specifically as follows: during the tunnel slag discharge stage, the excavation trolley is placed in the supported tunnel section, and the supporting points are marked at symmetrical positions on both sides of the arch frame centerline according to the spacing between the two longitudinal beams of the excavation trolley. Then, an integral arch frame is erected in the two brackets on the same group of jacks so that the two supporting points are located in the two brackets, and the fastening bolts are screwed into the vertical plates of the brackets to clamp and fix the arch frame front and back.

5. The comprehensive erection method for initial tunnel support according to any one of claims 1 to 4, characterized in that: The jack is a hydraulic jack, and the measuring range of the hydraulic jack is greater than the height from the top of the excavation trolley to the designed excavation surface.

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