Tunnel unilateral cable trench construction method and formwork

Abstract

The invention discloses a tunnel unilateral cable trench construction method and formwork, and relates to the technical field of tunnel cable trench construction.The combined unilateral cable trench formwork is designed and applied, firstly, a cable trench positioning datum line and a horizontal datum line are lofted, and cable trench steel bars are installed; then the combined unilateral cable trench formwork is used for installing and supporting a trench wall inner formwork and a trench wall outer formwork, then concrete is poured evenly in a layered mode according to the design requirement, when the concrete reaches certain strength, an ejector rod structure of the formwork can be loosened, the formworks are dismantled, and the formwork is moved to conduct construction of the next section along one side of the tunnel. According to the technology, application construction can be flexibly adjusted, use of different cable trench structures can be met, the working intensity of constructors can be reduced, the construction efficiency of cable trench walls can be improved, use of other equipment is not easily hindered by mounting and erecting, and the problem that a secondary lining structure is damaged due to the fact that a pull rod needs to be arranged for fixing a formwork in traditional single-side cable trench construction is solved.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel cable trench construction, in particular to a tunnel single-side cable trench construction method and a formwork. Background Art

[0002] With the continuous development of highway construction, the ratio of bridges to tunnels in mountainous areas is high, the tunnels are numerous and long, and the supporting facilities are relatively complete. The tunnel structure is mainly composed of two categories: the main structure and the auxiliary structure. Among them, the cable trench is an important part of the auxiliary structure, which provides space for the laying of cables and pipelines used in tunnel operations.

[0003] The formed tunnel usually uses the cable trench boundary as the lateral limit of the tunnel pavement width, where the side of the cable trench close to the pavement is the cable trench side wall cast by concrete. The cross section of the cable trench side wall is generally a rectangular cross section, which can be cast by ordinary molds. On-site casting of cable trenches is also an important part of tunnel engineering. Due to the shortcomings of traditional assembly formwork technology, such as large labor input, repeated splicing, limited support, and poor linear control, the constructed trenches are tortuous or misaligned, and the quality is poor, and it has been gradually eliminated in engineering construction. In order to reduce labor intensity, some construction units use automated trolleys as integrated formwork tools to construct and cast the side walls of cable trenches. The cable trench trolleys are capable of moving, accurately positioning, and reinforcing the shaped formwork, thereby saving most of the formwork time and reducing labor intensity. However, the cost of tunnel cable trench trolleys on the market is high. During construction, the cable trench trolley can only reach 12 meters at a time. Therefore, it is necessary to wait until the concrete has initially set before demolding and moving to the next section for use. It is installed across the tunnel. The simultaneous construction of cable trenches on both sides of the tunnel is likely to hinder the use of other construction equipment, which will delay the construction progress. In addition, the external dimensions of the formwork are not adjustable and cannot meet the construction width of the cable trench, so the adaptability is low.

[0004] In addition, it was found through actual construction that different design units have different standards for designing tunnel cable trenches. Tunnel cable trenches mainly have single-groove and three-groove structural designs of different sizes. The traditional formwork trolley construction is only used for one type of cable trench structure and cannot meet the cable trench construction requirements. Therefore, it is necessary to design a new tunnel single-sided cable trench construction technology. Summary of the invention

[0005] The purpose of the present invention is to provide a method and formwork for constructing a single-sided cable trench in a tunnel. The construction technology of the present application is not likely to hinder the use of other tunnel construction equipment. The formwork structure used is simple and easy to operate, and the application construction can be flexibly adjusted, which can improve the construction efficiency of the cable trench wall.

[0006] In order to achieve the purpose of the present invention, the technical solution adopted is: A method for constructing a single-side cable trench in a tunnel, the construction comprising the following steps: Step 1: Design the tunnel single-sided cable trench formwork according to the cable trench structure.

[0007] Step 2: Construction preparation: personnel, formwork, and equipment are in place, and the formwork is assembled on flat ground.

[0008] Step 3: Lay out the cable trench positioning reference line and horizontal reference line, lay out the template positioning installation edge line, then make the joint surface between the short side walls and the cable trough smooth and roughen it to ensure that the cable trough wall and the short side walls constructed later are firmly bonded.

[0009] Step 4: Rebar binding and installation. Cable trench steel bars are processed centrally and uniformly distributed to the construction site for installation and binding. The cable trench steel bars need to be tied firmly. The size, spacing and protective layer of the cable trench steel bars must meet the design and specification requirements.

[0010] Step 5. Vertically install the cable trench body template. The gap between the templates must be controlled within 2mm. The templates are connected with bolts. The uneven parts of the base are sealed with mortar after the template is closed. φ22 fixed steel bars are installed every 2 meters along the bottom of the template in the longitudinal direction of the base. They are firmly reinforced with iron wire and the concrete blocks on the board surface are removed.

[0011] Step 6: Transport the assembled formwork to the construction area, adjust the height of the adjustable running wheels according to the flatness of the ditch, and place it in the ditch to ensure that the main body of the formwork is placed horizontally.

[0012] Step 7. Set longitudinal and vertical round bars on the outer formwork of the trench wall, open the matching buckles at the same time, lower the inner and outer cross brace top bars, adjust the length of the inner and outer cross brace top bars, adjust the position and height of the top bars as needed, ensure a tight connection with the main frame and the formwork, and then fix the cable trench formwork, then remeasure the position of the formwork to ensure its verticality and verify the accuracy of the cable trench line type, and apply a release agent on the formwork after the remeasurement is completed.

[0013] Step 8. According to the flatness of the site, adjust the angle and length of the diagonal brace top rod and connect it with the fixed seat to ensure that its supporting surface is firmly fixed on the roadbed working surface.

[0014] Step nine, pour concrete evenly in layers according to design requirements. The cable trench is poured in two layers. The first layer is poured to the trench bottom elevation using an inserted vibrator. The second layer is poured to complete the cable trench to the designed top elevation at one time. Vibrate and compact the surface until it is smooth. After pouring to the designed top surface, perform the first smoothing in time. Perform the second smoothing when the concrete is initially set to ensure that the concrete surface is flat, free of bubbles, and has distinct corners.

[0015] Step 10. When the concrete reaches a certain strength, the top rod structure can be loosened and the formwork can be removed, and the trolley can be moved along one side of the tunnel to carry out the next section construction.

[0016] Further preferred: the tunnel single-sided cable trench formwork includes a formwork body, the formwork body is a gantry-type main frame spanning the outer trench wall of the single-sided cable trench, the formwork body includes multiple frames consisting of a first vertical rod, a third vertical rod and a cross rod, the two ends of the cross rod are respectively vertically connected to the top of the first vertical rod and the third vertical rod through a first vertical rod connecting seat and a third vertical rod connecting seat, the multiple frames are arranged in parallel and two adjacent frames are connected through a longitudinal rod, the longitudinal rods are respectively connected to the two ends of two adjacent cross rods, the longitudinal rods respectively detachably connect two adjacent first vertical rod connecting seats and two adjacent third vertical rod connecting seats, and can be adjusted according to the site The number of frames can be set arbitrarily according to construction requirements. The length of the trolley can be changed by connecting the longitudinal rods between the two frames to meet the construction requirements of the tunnel cable trench. The first vertical rod is placed outside the cable trench, and the third vertical rod is placed inside the cable trench. The two sides of the third vertical rod are respectively provided with inner mold cross brace top rods for supporting the inner template of the trench wall on both sides of the cable trench, and the bottom of the third vertical rod is installed with inner trench running wheels. The inner side of the first vertical rod is provided with an outer mold cross brace top rod for supporting the outer template of the trench wall, and the outer side of the first vertical rod is provided with an inclined brace top rod for connecting and supporting with the ground; the mold frame body located outside the cable trench is installed with adjustable running wheels with adjustable height. The contact end of the inner mold cross brace top rod and the inner template of the trench wall is provided with a round steel pad for expanding the contact surface, and the contact surface of the round steel pad and the inner template of the trench wall is additionally provided with a rubber pad. The template cross brace top rod is installed at the template connection position between the inner templates of the trench wall on both sides of the cable trench, and the contact end of the template cross brace top rod and the inner template of the trench wall is also provided with a round steel pad and a rubber pad for expanding the contact surface. The main body of the formwork is assembled on the leveled ground. When the main body of the formwork is moved to the position of the cable trench to be constructed, the running wheels in the trench are placed in the body of the cable trench, the height of the adjustable running wheels is adjusted, and the formwork is placed in the trench, ensuring that the main body of the formwork is placed horizontally.

[0017] Further preferred: the inner mold cross brace push rod comprises a screw sleeve, a mounting seat and a cross brace screw, one end of the cross brace screw is threadedly connected to the screw sleeve, and the length of the push rod is adjusted by rotating the screw, one end of the screw sleeve is hinged to the third vertical rod through the mounting seat, and the mounting seat is provided with a bottom support for limiting the downward swing position of the cross brace screw, so that the cross brace screw can only swing down to a horizontal state at the lowest; the third vertical rod is provided with an inner mold cross brace push rod buckle for retracting and releasing the cross brace screw; the outer mold cross brace push rod comprises a screw The screw sleeve is hingedly mounted on the first vertical rod through the external mold horizontal support top rod mounting seat, one end of the screw is threadedly connected in the screw sleeve, and the external mold horizontal support top rod mounting seat is provided with a bottom support for limiting the screw rod's swing position; the end of the screw is provided with a semicircular top support for connecting with the vertical round rod provided on the back of the trench wall external template, and a longitudinal round rod is provided between the vertical round rod and the back of the trench wall external template; the first vertical rod is provided with an external mold horizontal support top rod buckle for retracting the screw. In the non-working state, the top rod can be fastened to the vertical rod by the buckle to achieve more convenient installation and storage.

[0018] Further preferred: the diagonal support rod comprises a diagonal support rod mounting seat, a diagonal support screw rod sleeve and a diagonal support screw rod, the diagonal support screw rod sleeve is hinged on the first vertical rod through the diagonal support screw rod mounting seat, one end of the diagonal support screw rod is threadedly connected in the diagonal support screw rod sleeve, and the length of the rod is adjusted by rotating the screw rod, and the other end of the diagonal support screw rod is provided with a support seat supported on the ground; the first vertical rod is provided with a diagonal support rod buckle for retracting the diagonal support rod, and in the non-working state, the diagonal support rod can be fastened to the main frame using the diagonal support rod buckle to achieve more convenient installation and storage.

[0019] Further preferred: the adjustable walking wheel includes a screw lift, which is connected to two adjacent first vertical rods through a longitudinal rod, and the two ends of the longitudinal rod are respectively detachably connected to the two adjacent first vertical rods through connecting plates and connecting bolts. The screw lift is installed on the longitudinal rod and the lifting screw of the screw lift is arranged vertically. The bottom end of the lifting screw is equipped with a walking wheel, and the screw length is adjusted according to the screw lifting principle to ensure that the walking wheel is close to the ground and the mold frame body is placed horizontally to adapt to different complex working conditions; the screw lift is a manual and electric dual-purpose screw lift or a manual screw lift, and the screw lift is commercially purchased and installed for use.

[0020] Further preferred: when the cable trench is a three-groove structure, the cross bar includes a first cross bar and a second cross bar, one end of the first cross bar is detachably connected to one end of the second cross bar through a second vertical bar mounting seat, the bottom of the second vertical bar mounting seat is vertically connected to the second vertical bar, and the two sides of the second vertical bar are respectively provided with inner mold cross brace top bars for supporting the inner formwork of the trench wall, and a longitudinal bar is connected between the two adjacent second vertical bar mounting seats; the third vertical bar connecting seat extends away from the first vertical bar and is connected with a third cross bar, the bottom of the protruding end of the third cross bar is vertically connected to the fourth vertical bar through a fourth vertical bar mounting seat, the top of the fourth vertical bar is connected to the fourth vertical bar mounting seat, the two sides of the fourth vertical bar are respectively provided with inner mold cross brace top bars for supporting the inner formwork of the trench wall, and a longitudinal bar is connected between the two adjacent fourth vertical bar mounting seats.

[0021] Further preferred: the top end of the second cross bar is connected to the socket of the second vertical bar mounting seat, the upper end of the second cross bar is provided with a height adjustment hole for bolting to the second vertical bar mounting seat, and the lower end of the second cross bar is provided with a bottom plate bolting hole for bolting to the connecting ear of the bottom plate. During installation, it is necessary to bolt the bottom plate bolting hole of the second cross bar to the connecting ear of the groove bottom plate. During design, the groove bottom plate needs to be pre-welded with connecting ears, and the upper end of the second cross bar is inserted into the second vertical bar mounting seat and bolted to the corresponding height adjustment hole so that it is at a suitable height.

[0022] Further preferably, the top end of the fourth vertical rod is connected to the bottom end socket of the fourth vertical rod mounting seat, the upper end of the fourth vertical rod is provided with a height adjustment hole for bolting to the fourth vertical rod mounting seat, and the lower end of the fourth vertical rod is provided with a bottom plate bolting hole for bolting to the connecting ear of the bottom plate.

[0023] Further preferably, the second vertical rod mounting seat or the fourth vertical rod mounting seat comprises a sleeve, the sleeve is arranged horizontally, the two ends of the sleeve are used to pass the cross bar, the front and rear sides of the sleeve are provided with slot plates for connecting with the longitudinal rod, the bottom of the sleeve is provided with a sleeve pipe for connecting with the vertical rod sleeve, the sleeve pipe is provided with a connection hole corresponding to the height adjustment hole, and the sleeve and the slot plate are respectively provided with locking bolt holes for installing bolts to lock the rod. The structure of the first vertical rod connecting seat and the third vertical rod connecting seat can adopt a structure similar to the second vertical rod mounting seat or the fourth vertical rod mounting seat, which can meet the requirements of detachable connection of the rod.

[0024] The application of the single-sided cable trench construction method and formwork in this tunnel can flexibly adjust the application construction to meet the use of three cable trench design structures: single trench, double trench and triple trench. It is easy to operate, can reduce the work intensity of construction personnel, and improve the efficiency of cable trench wall construction. The installation and erection are not easy to hinder the use of other equipment. It solves the problems of traditional tunnel single-sided cable trench construction, such as large labor investment in assembling formwork technology, multiple repeated splicing, limited support, tortuous or misaligned ditches, and poor quality. It also avoids the problem of traditional single-sided cable trench construction requiring the setting of tie rods to fix the formwork and thus damaging the secondary lining structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the mold frame in Example 1; Figure 2 This is a schematic diagram of the end surface structure of the mold frame installation application in Example 1; Figure 3 It is a schematic diagram of the structure of the mold frame in Example 2; Figure 4 It is a schematic diagram of the end surface structure of the mold frame installation application in Example 2; Figure 5 It is a schematic diagram of the structure of the second and fourth vertical rod hinge seats; Figure 6 It is a structural schematic diagram of an adjustable traveling wheel; The names corresponding to the numbers in the figure are: 1. Adjustable running wheel; 2. First vertical bar; 3. External mold cross brace top bar; 4. Semicircular top support; 5. External mold cross brace top bar buckle; 6. First cross bar; 7. Internal mold cross brace top bar; 8. Mounting seat; 9. Second vertical bar; 10. Second vertical bar mounting seat; 11. Second cross bar; 12. Running wheel in the groove; 13. Internal mold cross brace top bar buckle; 14. Third vertical bar; 15. Fourth vertical bar; 16. Fourth vertical bar mounting seat; 17. Bottom plate bolting hole; 18. Height adjustment hole; 1 9. The third horizontal bar; 20. The third vertical bar connecting seat; 21. The longitudinal bar; 22. The first vertical bar connecting seat; 23. The diagonal support top rod; 24. The diagonal support top rod buckle; 25. The vertical round rod; 26. The longitudinal round rod; 27. The diagonal support top rod mounting seat; 28. The diagonal support screw rod sleeve; 29. ​​The diagonal support screw rod; 30. The supporting seat; 31. The walking wheel; 32. The lifting screw rod; 33. The screw rod lifting machine; 34. The sleeve tube; 35. The groove plate; 36. The locking bolt hole; 37. The sleeve. DETAILED DESCRIPTION

[0026] In order to make the technical solution and advantages of the present application more clear, the technical solution is clearly and completely described below in conjunction with embodiments. Example 1

[0027] A method for constructing a single-side cable trench in a tunnel, the construction comprising the following steps: Step 1: Design the tunnel single-side cable trench formwork according to the cable trench structure; Figure 1 As shown, the tunnel single-sided cable trench formwork includes a formwork body, which is a gantry-type main frame spanning the outer trench wall of the single-sided cable trench, and the formwork body includes multiple frames composed of a first vertical rod 2, a third vertical rod 14 and a cross rod, and the two ends of the cross rod are respectively vertically connected to the top of the first vertical rod 2 and the third vertical rod 14 through a first vertical rod connecting seat 22 and a third vertical rod connecting seat 20, and the multiple frames are arranged in parallel and two adjacent frames are connected through a longitudinal rod 21, and the longitudinal rod 21 is respectively connected to the two ends of two adjacent cross rods, and the longitudinal rod 21 respectively connects two adjacent first vertical rod connecting seats 22 and two adjacent third vertical rod connecting seats 20 in a detachable manner, which can be adjusted according to the site The number of frames can be set arbitrarily according to construction requirements. The length of the trolley can be changed by connecting the longitudinal rods between the two frames to meet the construction requirements of the tunnel cable trench. The first vertical rod 2 is placed outside the cable trench, and the third vertical rod 14 is placed inside the cable trench. The two sides of the third vertical rod 14 are respectively provided with inner mold cross brace top rods 7 for supporting the inner template of the trench wall on both sides of the cable trench, and the bottom of the third vertical rod 14 is installed with inner trench running wheels 12; the inner side of the first vertical rod 2 is provided with an outer mold cross brace top rod 3 for supporting the outer template of the trench wall, and the outer side of the first vertical rod 2 is provided with an inclined brace top rod 23 for connecting and supporting with the ground; the mold frame body located outside the cable trench is installed with an adjustable running wheel 1 with adjustable height. The contact end of the inner mold cross brace top rod 7 and the inner template of the trench wall is provided with a round steel pad for expanding the contact surface, and the contact surface between the round steel pad and the inner template of the trench wall is additionally provided with a rubber pad. The template cross brace top rod is installed at the template connection position between the trench wall templates on both sides of the cable trench. The contact end between the template cross brace top rod and the trench wall template is also provided with round steel pads and rubber pads for expanding the contact surface. The main body of the formwork is assembled on the leveled ground. After the main body of the formwork is moved to the position of the cable trench to be constructed, the trench running wheels are placed in the cable trench body, the height of the adjustable running wheels is adjusted, and it is placed in the ditch, and the main body of the formwork is ensured to be placed horizontally.

[0028] The inner mold cross brace push rod 7 includes a screw sleeve, a mounting seat 8 and a cross brace screw. One end of the cross brace screw is threadedly connected to the screw sleeve. The length of the push rod is adjusted by rotating the screw. One end of the screw sleeve is hinged to the third vertical rod 14 through the mounting seat 8. The mounting seat 8 is provided with a bottom support for limiting the downward swing position of the cross brace screw so that the cross brace screw can only swing down to a horizontal state at the lowest; the third vertical rod 14 is provided with an inner mold cross brace push rod buckle 13 for retracting and releasing the cross brace screw; the outer mold cross brace push rod 3 includes a screw sleeve, a screw The screw rod and the outer mold cross brace top rod mounting seat, the screw rod sleeve is hingedly mounted on the first vertical rod 2 through the outer mold cross brace top rod mounting seat, one end of the screw rod is threadedly connected in the screw rod sleeve, and the outer mold cross brace top rod mounting seat is provided with a bottom support for limiting the screw rod's swing position; the end of the screw rod is provided with a semicircular top support 4 for top connection with the vertical round rod 25 provided on the back of the trench wall outer template, and a longitudinal round rod 26 is provided between the vertical round rod 25 and the back of the trench wall outer template; the outer mold cross brace top rod buckle 5 for retracting the screw rod is provided on the first vertical rod 2. In the non-working state, the top rod can be fastened to the vertical rod by the buckle to achieve more convenient installation and storage.

[0029] The diagonal support rod 23 includes a diagonal support rod mounting seat 27, a diagonal support screw rod sleeve 28 and a diagonal support screw rod 29. The diagonal support screw rod sleeve 28 is hinged on the first vertical rod 2 through the diagonal support screw rod mounting seat 27. One end of the diagonal support screw rod 29 is threadedly connected in the diagonal support screw rod sleeve 28. The length of the rod is adjusted by rotating the screw rod. The other end of the diagonal support screw rod 29 is provided with a support seat 30 supported on the ground; the first vertical rod 2 is provided with a diagonal support rod buckle 24 for retracting and releasing the diagonal support rod 23. In the non-working state, the diagonal support rod can be fastened to the main frame using the diagonal support rod buckle to achieve more convenient installation and storage.

[0030] The adjustable walking wheel 1 includes a screw lift 33, which is connected to two adjacent first vertical rods 2 through a longitudinal rod 21. The two ends of the longitudinal rod 21 are respectively detachably connected to the two adjacent first vertical rods 2 through connecting plates and connecting bolts. The screw lift 33 is installed on the longitudinal rod 21 and the lifting screw 32 of the screw lift is arranged vertically. The bottom end of the lifting screw 32 is installed with a walking wheel 31. The screw length is adjusted according to the screw lifting principle to ensure that the walking wheel is close to the ground and the mold frame body is placed horizontally to adapt to different complex working conditions. The screw lift 33 is a manual and electric dual-purpose screw lift or a manual screw lift. The screw lift is purchased commercially and installed for use.

[0031] Step 2: Construction preparation: personnel, formwork, and equipment are in place, and the formwork is assembled on flat ground.

[0032] Step 3: Lay out the cable trench positioning reference line and horizontal reference line, lay out the template positioning installation edge line, then make the joint surface between the short side walls and the cable trough smooth and roughen it to ensure that the cable trough wall and the short side walls constructed later are firmly bonded.

[0033] Step 4: Rebar binding and installation. Cable trench steel bars are processed centrally and uniformly distributed to the construction site for installation and binding. The cable trench steel bars need to be tied firmly. The size, spacing and protective layer of the cable trench steel bars must meet the design and specification requirements.

[0034] Step 5. Vertically install the cable trench body template. The gap between the templates must be controlled within 2mm. The templates are connected with bolts. The uneven parts of the base are sealed with mortar after the template is closed. φ22 fixed steel bars are installed every 2 meters along the bottom of the template in the longitudinal direction of the base. They are firmly reinforced with iron wire and the concrete blocks on the board surface are removed.

[0035] Step 6. Transport the assembled formwork to the construction area, place the in-ditch running wheels at the bottom of the cable trench, adjust the height of the adjustable running wheels according to the flatness of the trench, and place them in the trench to ensure that the main body of the formwork is placed horizontally.

[0036] Step 7. Set longitudinal and vertical round bars on the outer formwork of the trench wall, open the matching buckles at the same time, lower the inner and outer cross brace top bars, adjust the length of the inner and outer cross brace top bars, adjust the position and height of the top bars as needed, ensure a tight connection with the main frame and the formwork, and then fix the cable trench formwork, then remeasure the position of the formwork to ensure its verticality and verify the accuracy of the cable trench line type, and apply a release agent on the formwork after the remeasurement is completed.

[0037] Step 8. According to the flatness of the site, adjust the angle and length of the diagonal brace top rod and connect it with the fixed seat to ensure that its supporting surface is firmly fixed on the roadbed working surface.

[0038] Step nine, pour concrete evenly in layers according to design requirements. The cable trench is poured in two layers. The first layer is poured to the trench bottom elevation using an inserted vibrator. The second layer is poured to complete the cable trench to the designed top elevation at one time. Vibrate and compact the surface until it is smooth. After pouring to the designed top surface, perform the first smoothing in time. Perform the second smoothing when the concrete is initially set to ensure that the concrete surface is flat, free of bubbles, and has distinct corners.

[0039] Step 10. When the concrete reaches a certain strength, the top rod structure can be loosened and the formwork can be removed, and the trolley can be moved along one side of the tunnel to carry out the next section construction. Example 2

[0040] A method for constructing a single-side cable trench in a tunnel, the construction comprising the following steps: Step 1: Design the tunnel single-side cable trench formwork according to the cable trench structure; Figure 4-6 As shown, the formwork includes a formwork body, which is a gantry main frame spanning the outer trench wall of a single-sided cable trench. The formwork body includes multiple frames consisting of a first vertical rod 2, a third vertical rod 14 and a cross rod, and the two ends of the cross rod are respectively vertically connected to the top of the first vertical rod 2 and the third vertical rod 14 through a first vertical rod connecting seat 22 and a third vertical rod connecting seat 20. The multiple frames are arranged in parallel and two adjacent frames are connected through a longitudinal rod 21, and the longitudinal rod 21 is respectively connected to the two ends of two adjacent cross rods. The longitudinal rod 21 detachably connects two adjacent first vertical rod connecting seats 22 and two adjacent third vertical rod connecting seats 20, which can be installed according to on-site construction requirements. The number of frames can be set arbitrarily, and the length of the trolley can be changed by connecting the longitudinal rods between the two frames to meet the construction requirements of the tunnel cable trench; the first vertical rod 2 is placed outside the cable trench, and the third vertical rod 14 is placed inside the cable trench. The two sides of the third vertical rod 14 are respectively provided with inner mold cross brace top rods 7 for supporting the inner template of the trench wall on both sides of the cable trench, and the bottom of the third vertical rod 14 is installed with inner trench running wheels 12; the inner side of the first vertical rod 2 is provided with an outer mold cross brace top rod 3 for supporting the outer template of the trench wall, and the outer side of the first vertical rod 2 is provided with an inclined brace top rod 23 for connecting and supporting with the ground; the mold frame body located outside the cable trench is installed with an adjustable running wheel 1 with adjustable height. The contact end of the inner mold cross brace top rod 7 and the inner template of the trench wall is provided with a round steel pad for expanding the contact surface, and the contact surface between the round steel pad and the inner template of the trench wall is additionally provided with a rubber pad. The template cross brace top rod is installed at the template connection position between the trench wall templates on both sides of the cable trench. The contact end between the template cross brace top rod and the trench wall template is also provided with round steel pads and rubber pads for expanding the contact surface. The main body of the formwork is assembled on the leveled ground. After the main body of the formwork is moved to the position of the cable trench to be constructed, the trench running wheels are placed in the cable trench body, the height of the adjustable running wheels is adjusted, and it is placed in the ditch, and the main body of the formwork is ensured to be placed horizontally.

[0041] The inner mold cross brace push rod 7 includes a screw sleeve, a mounting seat 8 and a cross brace screw. One end of the cross brace screw is threadedly connected to the screw sleeve. The length of the push rod is adjusted by rotating the screw. One end of the screw sleeve is hinged to the third vertical rod 14 through the mounting seat 8. The mounting seat 8 is provided with a bottom support for limiting the downward swing position of the cross brace screw so that the cross brace screw can only swing down to a horizontal state at the lowest; the third vertical rod 14 is provided with an inner mold cross brace push rod buckle 13 for retracting and releasing the cross brace screw; the outer mold cross brace push rod 3 includes a screw sleeve, a screw The screw rod and the outer mold cross brace top rod mounting seat, the screw rod sleeve is hingedly mounted on the first vertical rod 2 through the outer mold cross brace top rod mounting seat, one end of the screw rod is threadedly connected in the screw rod sleeve, and the outer mold cross brace top rod mounting seat is provided with a bottom support for limiting the screw rod's swing position; the end of the screw rod is provided with a semicircular top support 4 for top connection with the vertical round rod 25 provided on the back of the trench wall outer template, and a longitudinal round rod 26 is provided between the vertical round rod 25 and the back of the trench wall outer template; the outer mold cross brace top rod buckle 5 for retracting the screw rod is provided on the first vertical rod 2. In the non-working state, the top rod can be fastened to the vertical rod by the buckle to achieve more convenient installation and storage.

[0042] The diagonal support rod 23 includes a diagonal support rod mounting seat 27, a diagonal support screw rod sleeve 28 and a diagonal support screw rod 29. The diagonal support screw rod sleeve 28 is hinged on the first vertical rod 2 through the diagonal support screw rod mounting seat 27. One end of the diagonal support screw rod 29 is threadedly connected in the diagonal support screw rod sleeve 28. The length of the rod is adjusted by rotating the screw rod. The other end of the diagonal support screw rod 29 is provided with a support seat 30 supported on the ground; the first vertical rod 2 is provided with a diagonal support rod buckle 24 for retracting and releasing the diagonal support rod 23. In the non-working state, the diagonal support rod can be fastened to the main frame using the diagonal support rod buckle to achieve more convenient installation and storage.

[0043] The adjustable walking wheel 1 includes a screw lift 33, which is connected to two adjacent first vertical rods 2 through a longitudinal rod 21. The two ends of the longitudinal rod 21 are respectively detachably connected to the two adjacent first vertical rods 2 through connecting plates and connecting bolts. The screw lift 33 is installed on the longitudinal rod 21 and the lifting screw 32 of the screw lift is arranged vertically. The bottom end of the lifting screw 32 is installed with a walking wheel 31. The screw length is adjusted according to the screw lifting principle to ensure that the walking wheel is close to the ground and the mold frame body is placed horizontally to adapt to different complex working conditions. The screw lift 33 is a manual and electric dual-purpose screw lift or a manual screw lift. The screw lift is purchased commercially and installed for use.

[0044] The cross bar includes a first cross bar 6 and a second cross bar 11. One end of the first cross bar 6 is detachably connected to one end of the second cross bar 11 through a second vertical bar mounting seat 10. The bottom of the second vertical bar mounting seat 10 is vertically connected to a second vertical bar 9. Both sides of the second vertical bar 9 are respectively provided with inner mold cross support top bars 7 for supporting the inner mold of the trench wall. A longitudinal bar 21 is connected between two adjacent second vertical bar mounting seats 10.

[0045] The top end of the second cross bar 11 is connected to the bottom end socket of the second vertical bar mounting seat 10, the upper end of the second cross bar 11 is provided with a height adjustment hole 18 for bolting to the fourth vertical bar mounting seat 16, and the lower end of the second cross bar 11 is provided with a bottom plate bolting hole 17 for bolting to the connecting ear of the bottom plate.

[0046] The third vertical rod connecting seat 20 is connected to a third cross rod 19 extending from the side away from the first vertical rod 2. The bottom of the extended end of the third cross rod 19 is vertically connected to the fourth vertical rod 15 through a fourth vertical rod mounting seat 16. The top of the fourth vertical rod 15 is connected to the fourth vertical rod mounting seat 16. The two sides of the fourth vertical rod 15 are respectively provided with inner mold cross bracing top rods 7 for supporting the inner mold of the trench wall. A longitudinal rod 21 is connected between two adjacent fourth vertical rod mounting seats 16.

[0047] The top end of the fourth vertical rod 15 is connected to the bottom end socket of the fourth vertical rod mounting seat 16, the upper end of the fourth vertical rod 15 is provided with a height adjustment hole 18 for bolting to the fourth vertical rod mounting seat 16, and the lower end of the fourth vertical rod 15 is provided with a bottom plate bolting hole 17 for bolting to the connecting ear of the bottom plate.

[0048] The second vertical rod mounting seat 10 and the fourth vertical rod mounting seat 16 include a sleeve 37, which is horizontally arranged. The two ends of the sleeve 37 are used to pass the cross bar. The front and rear sides of the sleeve 37 are provided with groove plates 35 for connecting with the longitudinal rod 21. The bottom of the sleeve 37 is provided with a sleeve tube 34 for connecting with the vertical rod. The sleeve tube 34 is provided with a connecting hole corresponding to the height adjustment hole 18. The sleeve 37 and the groove plate 35 are respectively provided with locking bolt holes 36 for installing bolts to lock the rod.

[0049] Step 2: Construction preparation: personnel, formwork, and equipment are in place, and the formwork is assembled on flat ground.

[0050] Step 3: Lay out the cable trench positioning reference line and horizontal reference line, lay out the template positioning installation edge line, then make the joint surface between the short side walls and the cable trough smooth and roughen it to ensure that the cable trough wall and the short side walls constructed later are firmly bonded.

[0051] Step 4: Rebar binding and installation. Cable trench steel bars are processed centrally and uniformly distributed to the construction site for installation and binding. The cable trench steel bars need to be tied firmly. The size, spacing and protective layer of the cable trench steel bars must meet the design and specification requirements.

[0052] Step 5. Vertically install the cable trench body template. The gap between the templates must be controlled within 2mm. The templates are connected with bolts. The uneven parts of the base are sealed with mortar after the template is closed. Along the bottom of the template supported by the third vertical rod 14, φ22 fixed steel bars are installed every 2 meters in the longitudinal direction of the base. They are firmly reinforced with iron wire and the concrete blocks on the board surface are removed.

[0053] Step 6. Transport the assembled formwork to the construction area, place the in-ditch running wheels at the bottom of the cable trench, adjust the height of the adjustable running wheels according to the flatness of the trench, and place them in the trench to ensure that the main body of the formwork is placed horizontally.

[0054] Step 7. Set longitudinal and vertical round bars on the outer formwork of the trench wall, open the matching buckles at the same time, lower the inner and outer cross brace top bars, adjust the length of the inner and outer cross brace top bars, adjust the position and height of the top bars as needed, ensure a tight connection with the main frame and the formwork, and then fix the cable trench formwork, then remeasure the position of the formwork to ensure its verticality and verify the accuracy of the cable trench line type, and apply a release agent on the formwork after the remeasurement is completed.

[0055] Step 8. According to the flatness of the site, adjust the angle and length of the diagonal brace top rod and connect it with the fixed seat to ensure that its supporting surface is firmly fixed on the roadbed working surface.

[0056] Step nine, pour concrete evenly in layers according to design requirements. The cable trench is poured in two layers. The first layer is poured to the trench bottom elevation using an inserted vibrator. The second layer is poured to complete the cable trench to the designed top elevation at one time. Vibrate and compact the surface until it is smooth. After pouring to the designed top surface, perform the first smoothing in time. Perform the second smoothing when the concrete is initially set to ensure that the concrete surface is flat, free of bubbles, and has distinct corners.

[0057] Step 10. When the concrete reaches a certain strength, the top rod structure can be loosened and the formwork can be removed, and the trolley can be moved along one side of the tunnel to carry out the next section construction.

[0058] The above description is not a limitation of the present application, and the present application is not limited to the above examples. Any changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present application should fall within the scope of protection of the present application.

Claims

1. A method for constructing a single-side cable trench in a tunnel, characterized in that: The construction process includes the following steps: Step 1: Design the tunnel single-side cable trench formwork according to the cable trench structure; Step 2: Construction preparation: personnel, formwork, and equipment are in place, and the formwork is assembled on flat ground; Step 3: Lay out the cable trench positioning reference line and horizontal reference line, lay out the template positioning installation edge line, then make the joint surface between the short side walls on both sides and the cable trench smooth, and use roughening treatment to ensure that the cable trench wall and the short side wall constructed later are firmly bonded; Step 4: Tie and install the steel bars. The cable trench steel bars are processed centrally and uniformly delivered to the construction site for installation and tying. The cable trench steel bars need to be tied firmly. The size, spacing and protective layer of the cable trench steel bars must meet the design and specification requirements. Step 5: Install the cable trench body template vertically. The gap between the templates must be controlled within 2mm. The templates are connected with bolts. The uneven parts of the base are sealed with mortar after the template is closed. φ22 fixed steel bars are installed every 2 meters along the bottom of the template in the longitudinal direction of the base. They are reinforced with iron wire and the concrete blocks on the board surface are removed. Step 6: Transport the assembled formwork to the construction area, adjust the height of the adjustable running wheels according to the flatness of the ditch, and place it in the ditch to ensure that the main body of the formwork is placed horizontally; Step 7. Set longitudinal round bars and vertical round bars on the outer template of the trench wall, open the matching buckle at the same time, lower the inner mold cross brace top bar and the outer mold cross brace top bar, adjust the length of the inner mold cross brace top bar and the outer mold cross brace top bar, adjust the position and height of the top bar as needed, ensure that the connection with the main frame and the template is tight, and then fix the cable trench template, and then re-measure the template position to ensure its verticality and verify the accuracy of the cable trench line type. After completing the re-measurement, apply a release agent on the template; Step 8: According to the flatness of the site, adjust the angle and length of the diagonal support top rod and connect it with the fixed seat to ensure that its supporting surface is firmly fixed on the roadbed working surface; Step 9. Pour concrete evenly in layers according to design requirements. The cable trench is poured in two layers. The first layer is poured to the bottom elevation of the trench. An inserted vibrator is used. The second layer is poured to the designed top elevation at one time. The surface is vibrated and smoothed. After pouring to the designed top surface, the first surface is smoothed in time. When the concrete is initially set, the second surface is smoothed to ensure that the concrete surface is flat, free of bubbles, and has clear corners. Step 10. When the concrete reaches a certain strength, the top rod structure can be loosened and the formwork can be removed, and the trolley can be moved along one side of the tunnel to carry out the next section construction.

2. The method for constructing a single-side cable trench in a tunnel according to claim 1, characterized in that: The mold frame comprises a mold frame body, which is a gantry-type main frame spanning the outer trench wall of a single-sided cable trench. The mold frame body comprises a plurality of frames composed of a first vertical rod (2), a third vertical rod (14) and a cross rod, the two ends of the cross rod being vertically connected to the top of the first vertical rod (2) and the third vertical rod (14) through a first vertical rod connecting seat (22) and a third vertical rod connecting seat (20), respectively. The plurality of frames are arranged in parallel and two adjacent frames are connected through a longitudinal rod (21), the longitudinal rod (21) being connected to the two ends of two adjacent cross rods, and the longitudinal rod (21) connecting two adjacent first vertical rod connecting seats (22) and two adjacent third vertical rods. The vertical rod connecting seat (20) is detachably connected, the first vertical rod (2) is arranged outside the cable trench, the third vertical rod (14) is arranged inside the cable trench, both sides of the third vertical rod (14) are respectively provided with inner mold cross bracing top rods (7) for supporting the inner mold of the trench wall on both sides of the cable trench, and the bottom of the third vertical rod (14) is provided with inner trench running wheels (12); the inner side of the first vertical rod (2) is provided with outer mold cross bracing top rods (3) for supporting the outer mold of the trench wall, and the outer side of the first vertical rod (2) is provided with oblique bracing top rods (23) for connecting and supporting with the ground; and adjustable running wheels (1) with adjustable height are installed on the mold frame body located outside the cable trench.

3. The method for constructing a single-side cable trench in a tunnel according to claim 2, characterized in that: The inner mold cross brace push rod (7) comprises a screw sleeve, a mounting seat (8) and a cross brace screw, one end of the cross brace screw is threadedly connected to the screw sleeve, one end of the screw sleeve is hinged to the third vertical rod (14) through the mounting seat (8), and a bottom bracket for limiting the downward swing position of the cross brace screw is arranged on the mounting seat (8); the outer mold cross brace push rod (3) comprises a screw sleeve, a screw and an outer mold cross brace push rod mounting seat, the screw sleeve is hingedly mounted on the first vertical rod (2) through the outer mold cross brace push rod mounting seat, one end of the screw is threadedly connected to the screw sleeve, and a bottom bracket for limiting the downward swing position of the screw is arranged on the outer mold cross brace push rod mounting seat; the end of the screw is provided with a semicircular top bracket (4) for top connection with a vertical round rod (25) arranged on the back of the trench wall outer template.

4. The method for constructing a single-side cable trench in a tunnel according to claim 2, characterized in that: The diagonal support rod (23) comprises a diagonal support rod mounting seat (27), a diagonal support screw rod sleeve (28) and a diagonal support screw rod (29); the diagonal support screw rod sleeve (28) is hinged to the first vertical rod (2) via the diagonal support screw rod mounting seat (27); one end of the diagonal support screw rod (29) is threadedly connected in the diagonal support screw rod sleeve (28); and the other end of the diagonal support screw rod (29) is provided with a support seat (30) supported on the ground.

5. The method for constructing a single-side cable trench in a tunnel according to claim 2, characterized in that: The adjustable running wheel (1) comprises a screw lift (33), wherein the screw lift (33) is connected to two adjacent first vertical rods (2) via a longitudinal rod (21), and the two ends of the longitudinal rod (21) are respectively detachably connected to the two adjacent first vertical rods (2) via a connecting plate and a connecting bolt, the screw lift (33) is mounted on the longitudinal rod (21) and the lifting screw (32) of the screw lift is arranged vertically, and the running wheel (31) is mounted at the bottom end of the lifting screw (32).

6. The method for constructing a single-side cable trench in a tunnel according to claim 2, characterized in that: The cross bar comprises a first cross bar (6) and a second cross bar (11), one end of the first cross bar (6) is detachably connected to one end of the second cross bar (11) via a second vertical bar mounting seat (10), a second vertical bar (9) is vertically connected to the bottom of the second vertical bar mounting seat (10), both sides of the second vertical bar (9) are respectively provided with inner mold cross bracing top bars (7) for supporting the inner mold of the trench wall, and a longitudinal bar (21) is connected between two adjacent second vertical bar mounting seats (10); the third vertical bar is connected to the A third cross bar (19) is extended and connected to the side of the receiving seat (20) away from the first vertical bar (2); the bottom of the extended end of the third cross bar (19) is vertically connected to the fourth vertical bar (15) via a fourth vertical bar mounting seat (16); the top of the fourth vertical bar (15) is connected to the fourth vertical bar mounting seat (16); inner mold cross bracing top bars (7) for supporting the inner mold of the trench wall are respectively arranged on both sides of the fourth vertical bar (15); and a longitudinal bar (21) is connected between two adjacent fourth vertical bar mounting seats (16).

7. The method for constructing a single-side cable trench in a tunnel according to claim 6, characterized in that: The top end of the second cross bar (11) is connected to the bottom end socket of the second vertical bar mounting seat (10), the upper end of the second cross bar (11) is provided with a height adjustment hole (18) for bolting to the second vertical bar mounting seat (10), and the lower end of the second cross bar (11) is provided with a bottom plate bolting hole (17) for bolting to the connecting ear of the bottom plate.

8. The method for constructing a single-side cable trench in a tunnel according to claim 6, characterized in that: The top end of the fourth vertical rod (15) is connected to the bottom end socket of the fourth vertical rod mounting seat (16), the upper end of the fourth vertical rod (15) is provided with a height adjustment hole (18) for bolting to the fourth vertical rod mounting seat (16), and the lower end of the fourth vertical rod (15) is provided with a bottom plate bolting hole (17) for bolting to the connecting ear of the bottom plate.

9. The method for constructing a single-side cable trench in a tunnel according to claim 7 or 8, characterized in that: The second vertical rod mounting seat (10) or the fourth vertical rod mounting seat (16) comprises a sleeve (37), the sleeve (37) being arranged horizontally, the two ends of the sleeve (37) being used for passing the cross rod, the front and rear sides of the sleeve (37) being provided with slot plates (35) for connecting with the longitudinal rod (21), the bottom of the sleeve (37) being provided with a sleeve pipe (34) for connecting with the vertical rod, the sleeve pipe (34) being provided with a connection hole corresponding to the height adjustment hole (18), and the sleeve (37) and the slot plate (35) being provided with locking bolt holes (36) for installing bolts to lock the rod.

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