Assembled box culvert vertical prefabricated light formwork and manufacturing method and box culvert prefabrication method

Abstract

The present invention discloses a prefabricated vertical light-weight template for assembled box culverts and a manufacturing method and a prefabricated method for box culverts, including a base, an outer mold, a connecting rod mechanism, an inner mold, an end mold and a hydraulic support mechanism. The base is composed of two longitudinal beams, three transverse beams and two walking platforms. The outer mold is composed of four integral templates, each template is attached with a steel plate inside and welded with a diagonal brace outside. The inner mold is composed of an inner layer of grid ribs and an outer layer of inner mold steel plate. The inner mold steel plate is stamped from a whole piece of steel plate. The whole section is provided with only one joint. Two longitudinal ribs are provided at the joint of the folded section. Walking wheels are provided at the lower end of the longitudinal ribs. The assembly and disassembly of the inner mold is realized by the extension and contraction of the hydraulic support mechanism. The outer mold of the present invention adopts an integral, large-block template design, which can be driven by a connecting rod mechanism or a hydraulic system. The inner mold is driven by a full hydraulic support. The whole section is provided with only one joint. Vertical casting is adopted, and the end plates are matched for production. The finished segment has a good appearance effect.

Description

Technical field:

[0002] The invention relates to a civil engineering technology, in particular to an assembled box culvert vertical prefabricated light formwork and a manufacturing method thereof and a box culvert prefabrication method. Background technology:

[0004] With the increasingly widespread use of prefabricated box culverts in highways, railways, municipal administration and other fields, its characteristics of high degree of mechanization and factory production, small impact of climate, short construction period, simple prefabrication, safe and fast installation, and reliable quality have been well known in many fields. It has become the preferred solution for related industries to compare solutions and has good development prospects.

[0005] In actual application, after multiple observations and analyses, it was found that prefabricated box culverts still have some shortcomings. For example, in areas with high seismic resistance and weak foundation, prefabricated box culverts are usually designed to be connected into a whole by setting sockets and spigots, connecting the ends and ends, and tensioning the steel bars. The segments are centrally prefabricated and assembled on site.

[0006] When segments are prefabricated centrally, errors in the production, installation, and turnover of the templates will lead to differences in the cross-sectional dimensions of the finished segments, such as the thickness of the bottom plate, top plate, side wall thickness, clear height, clear width, and the perpendicularity of the end to the longitudinal (length direction) axis. Although the deviation of a single template prefabricated product can be controlled within the allowable range, when a large number of segments of the same model produced by different templates are installed, the socket and plug ends will not be completely close together, that is, poor matching. After the segments are combined and prestressed, torsion, bending, stress concentration, local damage and peeling of the socket, different joint widths, and misalignment will occur, resulting in poor visual effects. In addition, since the joints cannot be completely close together, the waterproof ability is reduced.

[0007] Traditional prefabricated box culvert segment templates are mostly horizontal structures, and the inner molds are mostly foldable, with 2 to 3 turning points and 2 to 3 joints on the cross section. For segments with larger spans (L ≥ 3m), when horizontal construction is adopted, it is impossible to cast the entire structure, and the bottom plate needs to be cast first. In this way, the bottom plate of the inner mold must be made movable (lifting or sideways), which increases the joints, makes installation difficult, casting relatively difficult, and the appearance effect is not ideal. Summary of the invention:

[0009] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a prefabricated light formwork for an assembled box culvert with reasonable design, light structure, convenient use, reusability and conducive to factory production, and a method for making the same.

[0010] The technical solution of the present invention is:

[0011] A prefabricated light-weight vertical formwork for assembled box culverts, comprising a base, an outer formwork, a connecting rod mechanism, an inner formwork, an end formwork and a hydraulic support mechanism, wherein the base is composed of two longitudinal beams, three transverse beams and two walking platforms, wherein the longitudinal beams, transverse beams and walking platforms correspond to the structures of the outer formwork and the inner formwork; the outer formwork is composed of four integral formworks, each of which is welded into a grid structure by section steel, and a steel plate is pasted inside and welded to the ribs of the grid; two diagonal braces are arranged at intervals on the outer surface of each formwork, and a walking wheel is arranged at the lower end of each diagonal brace, and the walking wheel falls on the longitudinal beams and transverse beams; the inner formwork is composed of an inner layer of grid ribs and an outer layer of inner formwork steel plates The inner mold steel plate is stamped from a whole piece of steel plate, and only one seam is set on the entire cross-section. The left and lower sections are fixed sections, the upper section is a folded section, the seam is set in the middle, and the right side is a lateral displacement section. A bending point is set at the upper left, upper right and lower right corners of the inner mold respectively, and a longitudinal rib is set on both sides of each bending point to form a wedge-shaped opening. A transverse corner rib is set at the other turning point to enhance rigidity. Two longitudinal ribs are set at the seam of the folded section, and universal wheels are respectively installed at the bottom of the longitudinal ribs and the bottom of the middle longitudinal rib of the lateral displacement section. The universal wheels are supported on the walking platform, and the installation and removal of the inner mold are realized by the extension and contraction of the hydraulic support mechanism.

[0012] A support frame is provided on the side or end of the cross beam and the longitudinal beam, and the top end of the support frame is fixedly connected to the outer sleeve of the bearing. The rotary rod passes through the inner sleeve of the bearing and is fixedly connected to the inner sleeve. One end of the connecting rod is fixed on the rotary rod, and the other end is fixed to the longitudinal rib provided on the outer surface of the template in a hinged form. Short ribs are welded on the outer end of the rotary rod, and a steel pipe is inserted to form a handle. The steel pipe is rotated to drive the outer mold to open and close.

[0013] Two limiting steel plates are added to the bottom of the lower end of each diagonal brace, and the net distance between the limiting plates on both sides is slightly larger than the width of the longitudinal beam or the cross beam. A welded fence is added to the top of the diagonal brace, and the height and width of the fence are based on the convenience of personnel operation.

[0014] A longitudinal rib is arranged on each side of the joint of the upper folded section of the inner mold, and a longitudinal rib is arranged in the middle of the right outward section for connecting the hydraulic rod of the hydraulic support mechanism. Fasteners are installed on the longitudinal ribs on both sides of the joint to fix and clamp them.

[0015] According to the design of the box culvert segment, the socket end plate is arranged at the lower end, arranged along the longitudinal beam and the transverse beam direction of the base, and all are fixed on the base. The inner mold and the outer mold are respectively close to the inner and outer sides of the end plate. The socket end plate and the flat end plate are both arranged at the upper end. The socket end plate is a movable structure and is fixed to the inner mold and the outer mold by bolts. There is no end plate at the flat end, which can be leveled when pouring concrete.

[0016] A method for manufacturing the vertical prefabricated lightweight formwork of the assembled box culvert comprises the following steps:

[0017] a. Production of the base:

[0018] Cut materials according to the designed size and model, and lay out and splice on a flat ground or pedestal. During the splicing process, strictly control the spacing between the longitudinal beams and cross beams and the positions of the two walking platforms, and level each component to ensure that the top surface of the base is horizontal. During the welding process, spot weld each part first, and then weld after leveling to avoid local deformation;

[0019] b. Production of the outer mold:

[0020] (1) Cut materials according to the designed size and model, weld them into a grid-shaped frame, strengthen the longitudinal ribs connected to the diagonal braces, and weld the entire steel plate on the inner layer. During the welding process, take measures such as cooling to avoid local bending and concavity of the steel plate;

[0021] (2) Fabrication and installation of diagonal braces. Cut materials according to the designed size and model. Each outer mold is equipped with two diagonal braces, and their spacing is the same as the center spacing of the longitudinal beams and cross beams. Two running wheels are installed at the bottom of each diagonal brace. The diagonal brace is welded to the longitudinal ribs on the outside of the template into a whole. The verticality of the template is strictly controlled during welding;

[0022] (3) After welding is completed, the entire template is erected on the base, and the walking wheels are placed on the longitudinal beams and cross beams. It is driven slowly by hand to check its stability during walking, and its center of gravity is adjusted by counterweighting the diagonal braces;

[0023] (4) According to the spacing between the longitudinal beams and cross beams of the base and the requirements of manual operation, select appropriate types of steel bars or steel pipes as the rotating rods, weld three short bars at the manual operation end, distributed at 120 degrees, and weld short bars at the ends or sides of the two longitudinal beams and cross beams on one side as the rotating rod brackets;

[0024] (5) Pass the two bearings through the rotating rod, first spot weld the bearing outer sleeve to the top of the bracket, and make sure the elevations of the two bearing top surfaces are consistent, then spot weld the bearing inner sleeve to the rotating rod;

[0025] (6) Adjust the opening and closing range of the outer mold on site, and install one end of the two processed connecting rods at the hinge point on the longitudinal rib of the outer mold, and spot weld the other end to the rotating rod for a short while. The outer mold is driven manually to rotate with the rotating rod. After determining the appropriate position together, spot weld one end of the connecting rod to the rotating rod;

[0026] (7) Install the processed fence on the top of the diagonal brace, connect it by welding or bolting, and check the stability of the template when walking again. If necessary, adjust the counterweight on the diagonal brace to maintain stability, and weld the limiting steel plate on the outside of the walking wheel at the bottom of the diagonal brace so that the inner spacing is slightly larger than the base width;

[0027] c. Production of inner mold:

[0028] (1) Select a whole steel plate with uniform texture, appropriate thickness and smooth surface, punch it on special equipment, make the full section of the inner mold, and set the cross section of the steel plate into a step form at the joint. Check the cross-sectional dimensions of the stamped steel plate, and make slight corrections with a jack on a special workbench. Fix the section after meeting the accuracy requirements;

[0029] (2) Select appropriate steel sections and weld them on the inside of the section according to the designed position to form longitudinal ribs and transverse ribs. Welding should be carried out at intervals on all four sides to avoid concentrated welding on the same side, which may cause deformation of the steel plate wing.

[0030] (3) Set reinforcing ribs at the designed positions in the middle of the four sides of the section, and weld a hinge point in the middle of the reinforcing ribs, i.e., the jack support point;

[0031] (4) At the designed bending points, i.e., the turning points at the lower ends of the upper left, upper right, and lower right corners, a longitudinal rib is provided at each end, with a wedge-shaped opening, and a corner rib is welded at the adjacent turning points to increase the rigidity of the area;

[0032] (5) A universal wheel is installed at the lower end of the reinforcing ribs on both sides of the joint of the folded section and the lower end of the reinforcing rib in the middle of the side shift section, respectively, and supported on the walking platform of the base;

[0033] d. Production of end mold:

[0034] In order to reasonably match the segments and facilitate demoulding, the socket template of the end mold is set at the bottom, that is, welded and fixed on the base, and the inner and outer molds are installed close to its side;

[0035] The socket end plate is located at the top and is movable. It is connected to the outer mold by bolts. To ensure the installation effect, the segments of the same unit are installed in sequence and the socket and plug templates are processed by the same equipment to ensure good matching and smooth installation. There is no end plate for the flat mouth. It can be leveled after pouring to the top surface.

[0036] The overall installation and debugging process of the assembled box culvert vertical prefabricated lightweight formwork is:

[0037] a. Base positioning and layout:

[0038] Choose a flat and solid ground, place the base on it, then measure the elevation of the top surface of the base, and take appropriate measures such as support to ensure that the top surface of the base is level. Release the lower socket end plate position and the inner mold walking wheel and support position according to the design. After checking that they are correct, connect the end plate and the top surface of the base into a whole through electric welding;

[0039] b. Inner mold installed in place:

[0040] Glue waterproof tapes to the inside and outside of the end plate, hoist the inner mold in place as a whole, make its inner side fit with the inner side of the end plate, use rod support or screw support to make it fit tightly with the end plate, and check the cross-sectional dimensions, verticality and tightness of the inner mold with the end plate at the same time. If there is a dimensional error exceeding the standard or the fit is not tight, correct the cross-sectional dimensions of the inner mold or the position of the end plate as appropriate until the cross-sectional dimensions, verticality and sealing meet the requirements;

[0041] c. Fixed inner mold:

[0042] According to the design requirements, the left side and the lower section of the inner mold are fixed sections, and a pad is added to the bottom. The pad has holes and is connected to the base through bolts to form a whole.

[0043] Universal wheels are installed at the bottom of the longitudinal ribs on both sides of the joint of the folded section so that they are supported on the walking platform. Similarly, universal wheels are installed at the bottom of the middle longitudinal ribs of the side shift section so that they are supported on the walking platform. Finally, the inner mold is temporarily fixed;

[0044] d. Install hydraulic components:

[0045] Install the oil pump at a suitable position on the base, fix the control box at a suitable position on the inner mold fixed section, and install the three hydraulic rods in the following order:

[0046] The first hydraulic rod connects the hinge point on the middle longitudinal rib of the left fixed section of the inner mold with the hinge point on the left half longitudinal rib of the folded section; the second hydraulic rod connects the hinge point on the right half longitudinal rib of the folded section with the hinge point on the middle longitudinal rib of the right side displacement section; the third hydraulic rod connects the hinge point on the middle longitudinal rib of the right side displacement section with the hinge point on the middle longitudinal rib of the lower fixed section;

[0047] e. Hydraulic system debugging:

[0048] Install the oil pipes respectively, connect the hydraulic rod and the oil pump, then connect the power supply between the oil pump and the control box, fill the oil pump with hydraulic oil, start the oil pump, first exhaust the air in the pipeline, start the three hydraulic rods respectively for telescopic operation, observe the opening and closing of the inner mold folding section and the right side shifting section, and the tightness of the end plate until the adjustment is appropriate;

[0049] f. External mold installation and debugging:

[0050] Lift the four outer molds that are made into an integral whole into place, install the rotating rod and connecting rod, manually rotate the handle to push the outer mold to open and close, check the verticality of the inner wall, the sealing condition with the side of the lower end plate, and whether there is any twisting when opening and closing, etc.;

[0051] g. Overall debugging:

[0052] Adjust the inner and outer molds into place at the same time, check the cross-sectional dimensions, joint sealing, tightness of fasteners after assembly, and correct the deviations;

[0053] Then follow the demoulding sequence and simulate the operation: first loosen the fasteners at the joints of the inner and outer molds; turn the handle to loosen the four outer molds respectively;

[0054] Start the oil pump and retract the first hydraulic rod, the second hydraulic rod and the third hydraulic rod in sequence. At the same time, determine the deformation at the three bending points and whether the left and lower fixed sections are deformed. The slight deformation is used as the basis to determine the extension and retraction range of the hydraulic rod.

[0055] A method for prefabricating a box culvert using the assembled box culvert vertical prefabricated lightweight formwork comprises the following steps:

[0056] a. Preparation:

[0057] Clean each formwork component, lubricate the rotation points, inspect the sand and stone materials, and verify and approve the construction mix ratio;

[0058] b. Steel bar manufacturing:

[0059] Mark the position of the segment main reinforcement and distribution reinforcement on the special formwork, install and weld the semi-finished products one by one according to the design drawings, set appropriate pads to control the protective layer, and report the finished products according to the procedures;

[0060] c. Inner mold positioning and steel bar installation:

[0061] By adjusting the hydraulic rod, the inner mold is positioned and the mold release agent is applied, and the outer mold is moved to the outermost end to facilitate the operator to put the steel bars in place and apply the mold release agent at the same time;

[0062] Lift the steel frame on the formwork with a special lifting device and slowly move it to the working surface to avoid hitting the formwork. During the falling process, be gentle and align to reduce the falling of the pads. After it is in place, check the condition of the protective layer, correct the deviation, make up for the fallen pads, install the embedded parts, and reserve holes;

[0063] d. Close the template and install the end plate:

[0064] Move the four outer molds into position, install the top socket end plate, check the joints and fasteners, and install the attached vibrator;

[0065] e. Concrete pouring:

[0066] Concrete is mixed centrally at the mixing station according to the approved construction ratio, transported by tank trucks, put into the hopper, lifted into the mold by a gantry crane, poured in layers, and vibrated by an attached vibrator in conjunction with an inserted vibrator. During the pouring process, check whether there is leakage at the template joints, whether the fasteners are loose, and whether the embedded parts and reserved holes are offset. If any problems occur, correct and handle them in a timely manner, and make synchronous curing test pieces. After pouring, cover the exposed concrete on the top for curing;

[0067] f. Dismantling the mold, lifting and shifting:

[0068] When the concrete strength reaches the requirements for demolding, first loosen the fasteners on the template, remove the socket end plate at the top, turn the handles on the four outer molds in turn, apply force slowly, pull the outer mold outward, and separate it from the concrete surface;

[0069] Start the oil pump to drive the three hydraulic rods to retract in turn, so that the folded section and the side shift section of the inner mold are separated from the inner concrete, until a tiny gap visible to the naked eye appears between the inner mold of the two fixed sections and the concrete;

[0070] After the concrete strength reaches the lifting requirements, hang the special lifting equipment on the preset lifting point of the segment, lift it slowly, and tilt it slightly to the lower left so that the inner molds of the two fixed segments can be smoothly separated from the concrete, and move the segment to the storage area.

[0071] In step a, apply detergent and cement slurry to the inside of the template, polish it carefully to remove rust and stains on the surface, and make the surface smooth and without marks;

[0072] Add lubricant to the connecting rods, swivel rods and hinge points, lay power lines in a safe location, make steel bar processing molds, conduct safety inspections on steel bar processing equipment, check the cutting and bending accuracy, check the lifting equipment, and handle relevant procedures.

[0073] The beneficial effects of the present invention are:

[0074] 1. The materials and equipment such as the profiles, plates, connecting rods, hydraulic rods, etc. of the present invention are all standardized products, which are easy to manufacture and purchase, convenient to use, quick to install and disassemble, high in precision, easy to finalize and standardize, and have strong applicability.

[0075] 2. The template designed in the present invention is a vertical integral prefabricated template. When pouring concrete, the construction height is reduced, and it is convenient to put into the mold and vibrate, which is beneficial to ensure the appearance quality of the component.

[0076] 3. The outer mold designed in the present invention is a large-block integral movable structure, which can be driven by a connecting rod mechanism or a hydraulic system. It only needs one person to operate, which is safe and reliable.

[0077] 4. The inner mold designed in the present invention is an integral stamped steel plate structure with only one joint in the entire section. Concrete is poured in layers from bottom to top, and the work is continuous. After the mold is removed, the internal appearance of the segment is good, which is suitable for projects with high requirements on appearance.

[0078] 5. The inner mold support designed by the present invention is a full hydraulic system. The folding section and the side shift section are both supported by walking wheels. The oil pump can adjust the opening and closing range of the inner mold according to the hydraulic rod to set the automatic starting and closing pressure to achieve intelligent control. The degree of automation is high, and the removal and installation of the inner mold can be completed by one person, with high work efficiency.

[0079] 6. The two fixed sections of the inner mold designed in the present invention are connected to the base as a whole. The demolding is achieved by adjusting the hydraulic rods in the order of 1→2→3, and the mold closing is carried out in the order of 3→2→1, so that each hydraulic rod has a force point, which is accurate and fast.

[0080] 7. The segment end plate scheme designed by the present invention pays special attention to the fact that the socket end plates of the same unit (such as 3 sections undergoing one tensioning) must be precisely processed on the same processing equipment, and the socket end plate is fixed to the lower end of the template, and the socket end plate is arranged at the upper end of the template, which makes the socket end plate easy to install and disassemble and convenient to cast. The dimensions of the socket and plug ends are accurately controlled and well matched, which can effectively reduce the problems of misalignment and distortion at the joints of the segments during installation.

[0081] 8. The segment formwork of the same unit (such as 3 sections for 1 tensioning) of the present invention can also be arranged in a mode of 1 set of outer formwork + n sets of inner formwork (the number of segments in 1 unit), with the inner formwork fixed in situ, the outer formwork and the socket end plate rotating, which can reduce investment and is suitable for factory-scale production.

[0082] 9. The three bending points at the corners of the inner mold of the present invention can be slightly modified after being used a certain number of times. The corner ribs at the adjacent turning points can be removed, moved to the bending points for welding and fixing, and new bending points can be set to increase the service life of the inner mold.

[0083] 10. The present invention has a light structure, is easy to use, can be reused, and is conducive to factory production. It is widely used in highway, railway, municipal and other industries, and is particularly suitable for large-scale factory production and assembly construction. It is easy to finalize and mass produce and has good benefits. Description of the drawings:

[0085] Figure 1 It is a structural schematic diagram of the vertical prefabricated lightweight formwork for the assembled box culvert;

[0086] Figure 2 for Figure 1 The top view of the structure of the vertical prefabricated lightweight formwork of the assembled box culvert is shown;

[0087] Figure 3 for Figure 1 The structure diagram of the removal of the inner mold;

[0088] Figure 4 for Figure 1 Schematic diagram of the structure of the middle base. Specific implementation method:

[0090] Example: See Figure 1-Figure 4In the figure, 1-diagonal brace, 2-external mold, 3-longitudinal rib, 4-fence, 5-inner mold, 6-first hydraulic rod, 7-inner mold folding section, 8-second hydraulic rod, 9-corner rib, 10-bending point, 11-reinforcement rib, 12-inner mold side shift section, 13-third hydraulic rod, 14-handle, 15-short rib, 16-rotating rod, 17-connecting rod, 18-support frame, 19-base crossbeam, 20-base longitudinal beam, 21-inner mold folding section walking platform, 22-middle crossbeam, 23-inner mold side shift section walking platform, 24-first bending point, 25-second bending point, 26-third bending point, 27-reserved hole.

[0091] 1. Template production:

[0092] 1. Production of the base:

[0093] Cut materials according to the design size and model, and lay out and splice on a flat ground or pedestal. During the splicing process, strictly control the spacing between the base longitudinal beam 20 and the base cross beam 19 and the positions of the two walking platforms (the inner mold folding section walking platform 21 and the inner mold side shifting section walking platform 23, and an intermediate cross beam 22 is set between the inner mold folding section walking platform 21 and the base cross beam 19), and level each component to ensure that the top surface of the base is horizontal. During the welding process, spot weld each part first, and then weld after leveling to avoid local deformation.

[0094] 2. Production of outer mold 2:

[0095] (1) Cut materials according to the designed size and model, weld them into a grid-shaped frame, and strengthen the longitudinal ribs 3 connected to the diagonal brace 1. The inner layer is welded to the entire steel plate. During the welding process, measures such as cooling are taken to prevent the steel plate from being partially bent or dented.

[0096] (2) Fabrication and installation of diagonal braces 1. Cut materials according to the designed size and model. Each outer mold 2 is equipped with two diagonal braces 1, and their spacing is the same as the spacing between the longitudinal and transverse beams of the base (center spacing). Two bearings are installed at the bottom of each diagonal brace 1. The diagonal brace 1 is welded to the longitudinal rib 3 on the outside of the template 2 into a whole. The verticality of the template is strictly controlled during welding.

[0097] (3) After welding is completed, the entire template is erected on the base, and the walking wheels are placed on the longitudinal and transverse beams. It is driven slowly by hand to check its stability during walking, and its center of gravity is adjusted by counterweighting the diagonal braces.

[0098] (4) According to the spacing between the longitudinal beams and transverse beams of the base and the requirements of manual operation, select appropriate types of steel bars or steel pipes as the rotating rod 16, and weld three short bars 15 at the manual operation end, distributed at 120 degrees. Weld support frames 18 at the ends or sides of the two longitudinal (transverse) beams on one side as brackets for the rotating rod 16.

[0099] (5) Pass the two bearings through the rotating rod 16, first spot weld the bearing outer sleeve to the top of the support frame 18, and control the elevation of the top surfaces of the two bearings to be consistent, and then spot weld the bearing inner sleeve to the rotating rod 16.

[0100] (6) Adjust the opening and closing range of the outer mold on site, and install one end of the two processed connecting rods 17 at the hinge point on the outer mold longitudinal rib 3, and spot weld the other end to the rotating rod 16 for a short while. Drive the outer mold 2 manually to cooperate with the rotating rod 16 to rotate. After jointly determining the appropriate position, spot weld one end of the connecting rod 17 to the rotating rod.

[0101] (7) Install the processed fence 4 on the top of the diagonal brace 1 (weld or bolted), and check the stability of the template when walking again. If necessary, adjust the counterweight on the diagonal brace to maintain stability. And weld the limit steel plate on the outside of the walking wheel at the bottom of the diagonal brace so that the inner spacing is slightly larger than the base width.

[0102] 3. Production of inner mold 5:

[0103] (1) Select a whole steel plate with uniform texture, appropriate thickness and smooth surface, punch it on special equipment, make the full section of the inner mold, and set the cross section of the steel plate into a step form at the joint. Check the cross-sectional dimensions of the stamped steel plate, and make slight corrections with a jack on a special workbench. Fix the section after meeting the accuracy requirements.

[0104] (2) Select appropriate steel sections and weld them on the inside of the section according to the designed position to form longitudinal ribs and transverse ribs. Welding should be carried out at intervals on all four sides to avoid concentrated welding on the same side, which may cause deformation of the steel plate.

[0105] (3) A reinforcing rib 11 is arranged at the designed position in the middle of the four sides of the cross section, and a hinge point (i.e., a jack support point) is welded in the middle of the reinforcing rib 11 (1 / 2 height).

[0106] (4) At the designed bending points, i.e., the turning points at the lower ends of the upper left, upper right, and lower right corners, a longitudinal rib is provided at each end, with a wedge-shaped opening, and a corner rib 9 is welded at the adjacent turning points to increase the rigidity of the parts. The three bending points 10 are: the first bending point 24, the second bending point 25, and the third bending point 26.

[0107] (5) A universal wheel is installed at the lower end of the reinforcing ribs on both sides of the joint of the inner mold folding section 7 and the lower end of the middle reinforcing rib of the inner mold side displacement section 12, respectively, and supported on the two walking platforms of the base.

[0108] 4. Production of end mold:

[0109] In order to reasonably match the segments and facilitate demoulding, the socket template of the end mold is set at the bottom, that is, it is welded and fixed on the base, and the inner mold and outer mold are installed close to its side.

[0110] The socket end plate is located at the top and is movable, connected to the outer mold by bolts. To ensure the installation effect, the segments of the same unit (such as 3 sections tensioned to form a section) are processed with the same equipment according to the installation sequence to achieve good matching and smooth installation. There is no end plate for the flat mouth, and it can be leveled after pouring to the top surface.

[0111] 2. Overall installation and debugging of template:

[0112] 1. Position and lay out the base:

[0113] Choose a flat and solid ground, place the base on it, then measure the elevation of the top surface of the base, and take appropriate measures such as pads to ensure that the top surface of the base is level. Release the position of the lower socket end plate and the support position of the inner mold walking wheel (universal wheel) according to the design. After checking that they are correct, connect the end plate and the top surface of the base into a whole through electric welding.

[0114] 2. Install the inner mold in place:

[0115] Glue waterproof tape (5mm thick) on the inside and outside of the end plate, hoist the inner mold in place as a whole, make its inner side fit with the inner side of the end plate, take support measures (such as rod support, screw support) to make it fit tightly with the end plate, and check the cross-sectional dimensions, verticality and tightness of the inner mold with the end plate. If the dimensional error exceeds the standard or the fit is not tight, the cross-sectional dimensions of the inner mold can be corrected (on a special pedestal) or the position of the end plate can be corrected as needed until the cross-sectional dimensions, verticality and sealing meet the requirements.

[0116] 3. Fixed inner mold:

[0117] According to the design requirements, pads are added to the left side (fixed section) and the bottom of the lower section (fixed section) of the inner mold. Holes are opened on the pads, which are connected to the base as a whole through bolts.

[0118] Universal wheels are installed at the bottom of the longitudinal ribs on both sides of the joint of the folded section to support them on the walking platform. Similarly, universal wheels are installed at the bottom of the middle longitudinal rib of the side shift section to support them on the walking platform. Finally, the inner mold is temporarily fixed.

[0119] 4. Install hydraulic components:

[0120] Install the oil pump at the appropriate position of the base (in the annular area outside the inner mold), and fix the control box at the appropriate position of the inner mold fixed section. Install the three hydraulic rods in the following order:

[0121] The first hydraulic rod 6 connects the hinge point on the middle longitudinal rib of the left fixed section of the inner mold and the hinge point on the left half longitudinal rib of the folded section.

[0122] The second hydraulic rod 8 connects the hinge point on the right half longitudinal rib of the folded section and the hinge point on the middle longitudinal rib of the right side displacement section.

[0123] The third hydraulic rod 13 connects the hinge point on the middle longitudinal rib of the right side displacement section with the hinge point on the middle longitudinal rib of the lower end fixed section.

[0124] 5. Hydraulic system debugging:

[0125] Install the oil pipes separately, connect the hydraulic rod and the oil pump, then connect the power supply between the oil pump and the control box, fill the hydraulic oil into the oil pump, start the oil pump, first exhaust the air in the pipeline, start the three hydraulic rods separately for telescopic operation, observe the opening and closing of the inner mold folding section, the right side shifting section, and the tightness of the fit with the end plate until it is adjusted appropriately.

[0126] 6. External mold installation and debugging:

[0127] Lift the four integral outer molds into place, install the swivel rod and connecting rod, manually rotate the handle to push the outer mold to open and close, check the verticality of the inner wall, the sealing condition with the side of the lower end plate, and whether there is any twisting when opening and closing.

[0128] 7. Overall debugging:

[0129] Adjust the inner and outer molds into place at the same time, check the cross-sectional dimensions, joint sealing, tightness of fasteners after assembly, and correct any deviations.

[0130] Then follow the demoulding sequence and simulate the operation: first loosen the fasteners at the joints of the inner and outer molds;

[0131] Turn the handle to loosen the four outer molds respectively;

[0132] Start the oil pump and retract hydraulic rod 1, hydraulic rod 2, and hydraulic rod 3 in sequence. At the same time, determine the deformation at the three bending points and whether the left and lower fixed sections have any deformation. The slight deformation is used as the basis to determine the extension and retraction range of the hydraulic rod.

[0133] 3. Box culvert prefabrication method:

[0134] 1. Preparation:

[0135] Apply detergent and cement slurry on the inside of the template and polish it carefully to remove surface rust and stains to make the surface smooth and free of marks.

[0136] Lubricate the connecting rods, rotating rods and hinge points, and lay power lines in safe locations. Make steel bar processing molds, conduct safety inspections on steel bar processing equipment, and check the accuracy of cutting and bending. Check lifting equipment and handle relevant procedures.

[0137] Inspect sand and stone materials, verify and approve construction mix ratios. Organize technical and safety briefings, and submit construction organization design.

[0138] 2. Steel bar manufacturing:

[0139] Mark the positions of segment main reinforcement and distribution reinforcement on the special formwork, install and weld the semi-finished products one by one according to the design drawings, set appropriate forms of pads to control the protective layer, and report the finished products according to the procedures.

[0140] 3. Inner mold positioning and steel bar installation:

[0141] By adjusting the hydraulic rod, the inner mold is positioned and the release agent is applied, and the outer mold is moved to the outermost end to facilitate the operator to put the steel bars in place and apply the release agent at the same time.

[0142] Lift the steel frame on the formwork with a special lifting device and slowly move it to the working surface to avoid hitting the formwork. During the falling process, be gentle and align to reduce the falling of the pads. After it is in place, check the condition of the protective layer, correct the deviation, make up for the fallen pads, install the embedded parts, and reserve holes.

[0143] 4. Close the template and install the end plate:

[0144] Move the four outer molds into place and install the top socket end plate (if the top is flat, there is no need to do this operation). Check the joints and fasteners and install the attached vibrator.

[0145] 5. Concrete pouring:

[0146] Concrete is mixed centrally at the mixing station according to the approved construction ratio, transported by tank trucks, put into the hopper, and lifted into the mold by the gantry crane. Layered pouring, vibrated by the attached vibrator and the inserted vibrator, and during the pouring process, check whether there is leakage at the template joints, whether the fasteners are loose, and whether the embedded parts and reserved holes are offset. If any problems occur, they will be corrected and handled in time. A synchronous curing test piece is also made, and after the pouring is completed, the exposed concrete on the top is covered and cured.

[0147] 6. Mould removal, lifting and shifting:

[0148] When the concrete strength reaches the requirement for demolding, first loosen the fasteners on the formwork, remove the socket end plate at the top, turn the handles on the four outer forms in turn, apply force slowly, pull the outer forms outward, and separate them from the concrete surface.

[0149] Start the oil pump to drive the three hydraulic rods to retract in turn, so that the folded section and the side-shifted section of the inner mold are separated from the inner concrete, until a tiny gap visible to the naked eye appears between the inner mold and the concrete of the two fixed sections.

[0150] After the concrete strength reaches the lifting requirements, hang the special lifting equipment on the preset lifting point of the segment, lift it slowly, and tilt it slightly to the lower left so that the inner molds of the two fixed segments can be smoothly separated from the concrete, and move the segment to the storage area.

[0151] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A prefabricated light-weight vertical formwork for assembled box culverts, comprising a base, an outer formwork, a connecting rod mechanism, an inner formwork, an end formwork and a hydraulic support mechanism, characterized in that: The base is composed of two longitudinal beams, three transverse beams and two walking platforms, and the longitudinal beams, transverse beams and walking platforms correspond to the structures of the outer mold and the inner mold; the outer mold is composed of four integral templates, each of which is welded into a grid structure by steel sections, and a steel plate is pasted inside and welded to the ribs of the grid. Two diagonal braces are arranged on the outer surface of each template at intervals, and a walking wheel is arranged at the lower end of each diagonal brace, and the walking wheel falls on the longitudinal beams and transverse beams; the inner mold is composed of an inner layer of grid ribs and an outer layer of inner mold steel plates, and the inner mold steel plates are stamped from a whole piece of steel plate, and the entire section is only provided with A joint, the left and lower sections of which are fixed sections, the upper section is a folding section, the joint is set in the middle, and the right side is a side shifting section. The three corners of the upper left, upper right and lower right of the inner mold are respectively provided with a bending point, and a reinforcing rib is provided on both sides of each bending point to form a wedge-shaped opening. Horizontal corner ribs are provided at adjacent turning points to enhance rigidity. Two longitudinal ribs are provided at the joint of the folding section, and universal wheels are respectively installed at the bottom of the longitudinal ribs and the bottom of the middle longitudinal rib of the side shifting section. The universal wheels are supported on the walking platform, and the installation and removal of the inner mold are realized by the extension and contraction of the hydraulic support mechanism; A support frame is provided on the side or end of the cross beam and the longitudinal beam, and the top end of the support frame is fixedly connected to the outer sleeve of the bearing. The rotary rod passes through the inner sleeve of the bearing and is fixedly connected to the inner sleeve. One end of the connecting rod is fixed on the rotary rod, and the other end is fixed to the longitudinal rib provided on the outer surface of the template in a hinged form. Short ribs are welded on the outer end of the rotary rod, and a steel pipe is inserted to form a handle. The steel pipe is rotated to drive the outer mold to open and close.

2. The prefabricated vertical lightweight formwork for assembled box culvert according to claim 1 is characterized by: Two limiting steel plates are added to the bottom of the lower end of each diagonal brace, and the net distance between the limiting steel plates on both sides is slightly larger than the width of the longitudinal beam or the cross beam. A welded fence is added to the top of the diagonal brace, and the height and width of the fence are based on the convenience of personnel operation.

3. The assembled box culvert vertical prefabricated lightweight formwork according to claim 1 is characterized by: A longitudinal rib is arranged on each side of the joint of the upper folded section of the inner mold, and a longitudinal rib is arranged in the middle of the right outward section for connecting the hydraulic rod of the hydraulic support mechanism. Fasteners are installed on the longitudinal ribs on both sides of the joint to fix and clamp them.

4. The assembled box culvert vertical prefabricated lightweight formwork according to claim 1 is characterized by: According to the design of the box culvert segment, the socket end plate is arranged at the lower end, arranged along the longitudinal beam and the transverse beam direction of the base, and all are fixed on the base. The inner mold and the outer mold are respectively close to the inner side and the outer side of the socket end plate. The socket end plate and the flat end plate are both arranged at the upper end. The socket end plate is a movable structure and is fixed to the inner mold and the outer mold by bolts. The flat end plate has no end plate and can be leveled when pouring concrete.

5. A method for manufacturing the prefabricated vertical lightweight formwork for an assembled box culvert according to any one of claims 1 to 4, comprising the following steps: a. Production of the base: Cut materials according to the designed size and model, and lay out and splice on a flat ground or pedestal. During the splicing process, strictly control the spacing between the longitudinal beams and cross beams and the positions of the two walking platforms, and level each component to ensure that the top surface of the base is horizontal. During the welding process, spot weld each part first, and then weld after leveling to avoid local deformation; b. Production of the outer mold: (1) Cut materials according to the designed size and model, weld them into a grid-shaped frame, strengthen the longitudinal ribs connected to the diagonal braces, and weld the entire steel plate on the inner layer. During the welding process, take cooling measures to avoid local bending and concavity of the steel plate; (2) Fabrication and installation of diagonal braces. Cut materials according to the designed size and model. Each outer mold is equipped with two diagonal braces, and their spacing is the same as the center spacing of the longitudinal beams and cross beams. Two running wheels are installed at the bottom of each diagonal brace. The diagonal brace is welded to the longitudinal ribs on the outside of the template into a whole. The verticality of the template is strictly controlled during welding; (3) After welding is completed, the entire template is erected on the base, and the walking wheels are placed on the longitudinal beams and cross beams. It is driven slowly by hand to check its stability during walking, and its center of gravity is adjusted by counterweighting the diagonal braces; (4) According to the spacing between the longitudinal beams and cross beams of the base and the requirements of manual operation, select appropriate types of steel bars or steel pipes as the rotating rods, weld three short bars at the manual operation end, distributed at 120 degrees, and weld short bars at the ends or sides of the two longitudinal beams and cross beams on one side as the rotating rod brackets; (5) Pass the two bearings through the rotating rod, first spot weld the outer sleeve of the bearing to the top of the support frame, and make sure that the top surface elevations of the two bearings are consistent, then spot weld the inner sleeve of the bearing to the rotating rod; (6) Adjust the opening and closing range of the outer mold on site, and install one end of the two processed connecting rods at the hinge point on the longitudinal rib of the outer mold, and spot weld the other end to the rotating rod for a short while. The outer mold is driven manually to rotate with the rotating rod. After determining the appropriate position together, spot weld the other end of the connecting rod to the rotating rod; (7) Install the processed fence on the top of the diagonal brace, connect it by welding or bolting, and check the stability of the template when walking again. If necessary, adjust the counterweight on the diagonal brace to maintain stability, and weld the limiting steel plate on the outside of the walking wheel at the bottom of the diagonal brace so that the inner spacing is slightly larger than the base width; c. Production of inner mold: (1) Select a whole steel plate with uniform texture, appropriate thickness and smooth surface, punch it on special equipment, make the full section of the inner mold, and set the cross section of the steel plate into a step form at the joint. Check the cross-sectional dimensions of the stamped steel plate, and make slight corrections with a jack on a special workbench. Fix the section after meeting the accuracy requirements; (2) Select appropriate steel sections and weld them on the inside of the section according to the designed position to form longitudinal ribs and transverse ribs. Welding should be carried out at intervals on all four sides to avoid concentrated welding on the same side, which may cause deformation of the steel plate wing. (3) Set reinforcing ribs at the designed positions in the middle of the four sides of the section, and weld a hinge point in the middle of the reinforcing ribs, i.e., the jack support point; (4) At the designed bending points, i.e., the turning points at the lower ends of the upper left, upper right, and lower right corners, a longitudinal rib is provided at each end, with a wedge-shaped opening, and a transverse corner rib is welded at the adjacent turning points to increase the rigidity of the area; (5) A universal wheel is installed at the lower end of the longitudinal ribs on both sides of the joint of the folded section and the lower end of the middle longitudinal rib of the side shift section, respectively, and supported on the walking platform of the base; d. Production of end mold: In order to reasonably match the segments and facilitate demoulding, the socket end plate of the end mold is set at the bottom, that is, welded and fixed on the base, and the inner mold and outer mold are installed close to its side; The socket end plate is located at the top and is movable. It is connected to the outer mold by bolts. To ensure the installation effect, the segments of the same unit are installed in sequence and the socket and plug end plates are processed by the same equipment to ensure good matching and smooth installation. There is no end plate for the flat end. It can be leveled after pouring to the top surface.

6. The method according to claim 5, characterized in that: The overall installation and debugging process of the assembled box culvert vertical prefabricated lightweight formwork is: a. Base positioning and layout: Choose a flat and solid ground, place the base on it, then measure the elevation of the top surface of the base, and take appropriate support measures to ensure that the top surface of the base is level. Release the position of the lower socket end plate and the support position of the inner mold walking wheel according to the design. After checking that they are correct, connect the end plate and the top surface of the base into a whole through electric welding; b. Inner mold installed in place: Glue waterproof tapes to the inside and outside of the end plate, hoist the inner mold in place as a whole, make its inner side fit with the inner side of the end plate, use rod support or screw support to make it fit tightly with the end plate, and check the cross-sectional dimensions, verticality and tightness of the inner mold with the end plate at the same time. If there is a dimensional error exceeding the standard or the fit is not tight, correct the cross-sectional dimensions of the inner mold or the position of the end plate as appropriate until the cross-sectional dimensions, verticality and sealing meet the requirements; c. Fixed inner mold: According to the design requirements, the left side and the lower section of the inner mold are fixed sections, and a pad is added to the bottom. The pad has holes and is connected to the base through bolts to form a whole. Universal wheels are installed at the bottom of the longitudinal ribs on both sides of the joint of the folded section so that they are supported on the walking platform. Similarly, universal wheels are installed at the bottom of the middle longitudinal ribs of the side shift section so that they are supported on the walking platform. Finally, the inner mold is temporarily fixed; d. Install the hydraulic support mechanism: Install the oil pump at a suitable position on the base, fix the control box at a suitable position on the inner mold fixed section, and install the three hydraulic rods in the following order: The first hydraulic rod connects the hinge point on the middle longitudinal rib of the left fixed section of the inner mold with the hinge point on the left half longitudinal rib of the folded section; the second hydraulic rod connects the hinge point on the right half longitudinal rib of the folded section with the hinge point on the middle longitudinal rib of the right side displacement section; the third hydraulic rod connects the hinge point on the middle longitudinal rib of the right side displacement section with the hinge point on the middle longitudinal rib of the lower fixed section; e. Hydraulic system debugging: Install the oil pipes respectively, connect the hydraulic rod and the oil pump, then connect the power supply between the oil pump and the control box, fill the oil pump with hydraulic oil, start the oil pump, first exhaust the air in the pipeline, start the three hydraulic rods respectively for telescopic operation, observe the opening and closing of the inner mold folding section and the right side shifting section, and the tightness of the end plate until the adjustment is appropriate; f. External mold installation and debugging: Lift the four outer molds that are made into an integral whole into place, install the rotating rod and connecting rod, and manually rotate the handle to push the outer mold to open and close, check the verticality of the inner wall, the sealing condition with the side of the lower end plate, and whether there is any twisting when opening and closing; g. Overall debugging: Adjust the inner and outer molds into place at the same time, check the cross-sectional dimensions, joint sealing, tightness of fasteners after assembly, and correct the deviations; Then follow the demoulding sequence and simulate the operation: first loosen the fasteners at the joints of the inner and outer molds; turn the handle to loosen the four outer molds respectively; Start the oil pump and retract the first hydraulic rod, the second hydraulic rod and the third hydraulic rod in sequence. At the same time, measure the deformation at the three bending points and whether the left and lower fixed sections are deformed. The extension and retraction range of the hydraulic rod is determined based on the slight deformation of the left and lower fixed sections.

7. A method for prefabricating a box culvert using the vertical prefabricated lightweight formwork of any one of claims 1 to 4, comprising the following steps: a. Preparation: Clean each formwork component, lubricate the rotation points, inspect the sand and stone materials, and verify and approve the construction mix ratio; b. Steel bar manufacturing: Mark the position of the segment main reinforcement and distribution reinforcement on the special formwork, install and weld the semi-finished products one by one according to the design drawings, set appropriate pads to control the protective layer, and report the finished products according to the procedures; c. Inner mold positioning and steel bar installation: By adjusting the hydraulic rod, the inner mold is positioned and the mold release agent is applied, and the outer mold is moved to the outermost end to facilitate the operator to put the steel bars in place and apply the mold release agent at the same time; Lift the steel frame on the formwork with a special lifting device and slowly move it to the working surface to avoid hitting the formwork. During the falling process, be gentle and align to reduce the falling of the pads. After it is in place, check the condition of the protective layer, correct the deviation, make up for the fallen pads, install the embedded parts, and reserve holes; d. Close the template and install the end plate: Move the four outer molds into position, install the top socket end plate, check the joints and fasteners, and install the attached vibrator; e. Concrete pouring: Concrete is mixed centrally at the mixing station according to the approved construction ratio, transported by tank trucks, put into the hopper, lifted into the mold by a gantry crane, poured in layers, and vibrated by an attached vibrator in conjunction with an inserted vibrator. During the pouring process, check whether there is leakage at the template joints, whether the fasteners are loose, and whether the embedded parts and reserved holes are offset. If any problems occur, correct and handle them in a timely manner, and make synchronous curing test pieces. After pouring, cover the exposed concrete on the top for curing; f. Dismantling the mould, lifting and shifting: When the concrete strength reaches the requirements for demolding, first loosen the fasteners on the template, remove the socket end plate at the top, turn the handles on the four outer molds in turn, apply force slowly, pull the outer mold outward, and separate it from the concrete surface; Start the oil pump to drive the three hydraulic rods to retract in turn, so that the folded section and the side shift section of the inner mold are separated from the inner concrete, until a tiny gap visible to the naked eye appears between the inner mold of the two fixed sections and the concrete; After the concrete strength reaches the lifting requirements, hang the special lifting equipment on the preset lifting point of the segment, lift it slowly, and tilt it slightly to the lower left so that the inner molds of the two fixed segments can be smoothly separated from the concrete, and move the segment to the storage area.

8. The box culvert prefabrication method according to claim 7 is characterized in that: In step a, the inner side of the template is coated with a cleaning agent and cement slurry, and the surface is carefully polished to remove rust and stains, so that the surface is smooth and free of marks; Add lubricant to the connecting rods, swivel rods and hinge points, lay power lines in a safe location, make steel bar processing molds, conduct safety inspections on steel bar processing equipment, check the cutting and bending accuracy, check the lifting equipment, and handle relevant procedures.

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