Mobile segmental beam wet joint UHPC rapid closure construction method

Abstract

The invention discloses a movable segment beam wet joint UHPC rapid closure construction method which comprises the following steps: S1, wet joint arrangement: wet joints are located in the midspan of a side span, the midspan of a middle span and two sides of the top of a transition pier of each box beam, and the length of the wet joints is 8-20 cm; s2, a closure section is hoisted, a wet joint locking device and a formwork are installed, specifically, a temporary positioning device is installed to lock the box girders on the two sides and the closure section, and then the wet joint formwork is installed; s3, wet joint mixing is conducted, specifically, strain hardening type UHPC is mixed on the beam face through a UHPC mixer, and after mixing is completed, the mixture is put into a pouring hopper of 1 cubic meter; s4, closure section wet joint concrete is poured, specifically, a bridge girder erection machine lifting crown block is adopted to lift a pouring hopper to a wet joint for pouring, and for the position with the pouring height larger than two meters, a chute is arranged on site for discharging; and S5, formwork dismantling, wherein after the joint strength of the closure section reaches the concrete strength standard, the wet joint formwork and the temporary positioning device are dismantled.

Description

Technical Field

[0001] The present application relates to the technical field of segmental beam construction, and in particular to a method for rapid closure construction of movable segmental beam wet joints using UHPC. Background Art

[0002] During the construction of segmental beams of bridges, the symmetrical cantilever splicing process of the bridge erection machine is generally adopted. The wet joint design of the closure section adopts C55 concrete cast-in-place construction to complete the closure. The design requires that the C55 concrete reaches a compressive strength of 55MPa and an elastic modulus of more than 32GPa before tensioning. It takes about 5 days to reach this strength, which will greatly affect the construction period. Summary of the Invention

[0003] The purpose of this application is to provide a mobile segmental beam wet joint UHPC rapid closure construction method to improve the problem of long wet joint construction period.

[0004] In the first aspect, the present application provides a method for rapid closure of wet-jointed UHPC segments using the following technical solutions: A movable segmental beam wet joint UHPC rapid closure construction method comprises the following steps: S1. Wet joint arrangement: Wet joints are located at the mid-span of the side span, mid-span of the middle span and both sides of the top of the transition pier of each box girder, with a length of 8 to 20 cm; S2. Hoist the closing section, install the tensioning device to prevent concrete temperature stress cracking, install the wet joint locking device and formwork: The bridge erection machine symmetrically suspends the construction segment beams to the maximum suspension state and then begins to hoist the closing section. After hoisting to the designed elevation, install the tensioning device to prevent concrete temperature stress cracking, continue to adjust the segment position and elevation, install the temporary positioning device to lock the box beams and closing section on both sides, and then install the wet joint formwork; S3. Wet joint mixing: Use a UHPC mixer to mix strain hardening UHPC on the beam surface, and discharge the material into a 1 cubic meter casting hopper after mixing; S4. Pouring wet joint concrete of the closing section: Use a bridge crane crane to lift the pouring hopper to the wet joint for pouring. For locations where the pouring height exceeds two meters, set up a chute on site for discharge; S5. Formwork removal: After the joint strength of the closed section reaches the concrete strength standard, remove the wet joint formwork and temporary positioning device.

[0005] By adopting the above technical solution and using strain-hardened UHPC as the casting material, the forming speed of wet joints can be increased, and the strength after forming can be improved, the construction efficiency can be improved, and the construction quality can be guaranteed. At the same time, the UHPC mixer mixes directly on the box girder surface, and can be poured immediately after mixing, which can not only save transportation time but also ensure that the poured concrete is in a suitable state, thereby further ensuring the forming quality; however, UHPC high-strength concrete has a rapid strength increase, which makes it greatly affected by the thermal expansion and contraction of the climate and is extremely prone to cracking. Therefore, a tensioning device to prevent concrete temperature stress cracking is installed to solve the problem of wet joint cracking.

[0006] Optionally, in step S4, the order of pouring wet joint concrete is to pour the bottom plate first, then pour the belly formwork, and finally pour the top plate. The surface of the top plate is roughened and covered with water for maintenance.

[0007] Optionally, in step S2, the wet joint is located between the closing section and the box beam, and the temporary positioning device includes a positioning frame and a limiter. The limiters are provided in three groups, and the three groups of limiters are respectively fixedly connected to two box beams and a closing section, and the positioning frame is fixedly connected to the three groups of limiters.

[0008] Through the above technical solution, three sets of limiters are first fixedly connected to two box girders and a closing section respectively, and then the three sets of limiters are connected to the positioning frame, thereby realizing the positioning and fixation of the closing section and the box girders on both sides, providing a stable foundation for subsequent construction.

[0009] Optionally, in step S2, the wet joint formwork includes a bottom formwork, two web forms, two top forms and two side forms from the middle to both sides, the side forms are hinged to the adjacent top forms, and the ends of the side forms away from the top forms are connected with hanging rings; the box beam and the closing section are provided with the same set of positioning plates, and each set of positioning plates is provided with multiple positioning plates along the width direction of the box beam, and the positioning plates are located above the wet joints, and the positioning plates are connected to the bottom formwork or the top formwork through hanging rods.

[0010] Through the above technical solution, the side formwork and the top formwork are hinged to better fit the box girder. At the same time, the lifting ring facilitates the lifting of the wet joint formwork as a whole, and the positioning plate can cooperate with the lifting rod to fix the wet joint formwork as a whole between the box girder and the closing section by pulling.

[0011] Optionally, a reinforcement plate is provided under the wet joint template, and the reinforcement plate includes a first reinforcement transverse plate, two reinforcement oblique plates and two second reinforcement transverse plates. The first reinforcement transverse plate is fixedly connected to the bottom template, and the two second reinforcement transverse plates are respectively fixedly connected to the two top templates, and the two reinforcement oblique plates are respectively supported against the corresponding abdominal templates through a group of supporting members.

[0012] Through the above technical solution, the reinforcing plate can strengthen the wet joint formwork, reducing the possibility of the wet joint formwork bending during the lifting process and causing it to fit loosely with the box girder or the closing section. At the same time, the supporting parts can support the web formwork, ensuring that the web formwork and the box girder closing section fit tightly, reducing the possibility of concrete leakage.

[0013] Optionally, connecting holes for inserting the hanger are provided on the second reinforcing cross plate and the top mold, and the connecting holes are set through the second reinforcing cross plate and the top mold. A threaded section is provided at the bottom of the hanger, and the threaded section is threadedly connected to the inner wall of the connecting hole. The top of the hanger passes through the positioning plate and is threadedly connected with a locking nut.

[0014] By adopting the above technical solution, during installation, the hanger is passed through the positioning plate, and the threaded section is passed through the connecting hole and threadedly connected to the side wall of the connecting hole, so that the operator can complete the installation of the wet joint formwork above the box girder, reducing the risk of high-altitude construction.

[0015] Optionally, a sliding groove is provided on the side wall of the connecting hole, a slider slides in the sliding groove, an annular groove for inserting the slider is provided on the side wall of the threaded section, a compression spring is provided in the sliding groove, one end of the compression spring abuts against the end of the slider away from the sliding groove, and the other end abuts against the end of the sliding groove away from the annular groove, and a first inclined surface is provided on the end of the slider facing the sliding groove, and the first inclined surface is provided on the side of the slider facing the positioning plate.

[0016] By adopting the above technical solution, when the threaded section is threadedly connected to the inner hole of the connecting hole, the threaded section moves downward as a whole, first abutting against the first inclined surface, causing the slider to be pressed back into the slide groove, and then when the slide groove and the annular groove are aligned in the height direction, the slider pops out under the action of the compression spring and is stuck in the annular groove, realizing secondary fixation between the hanger and the top mold and the second reinforcing cross plate, cooperating with the connection between the threaded section and the inner wall of the connecting hole, ensuring a reliable connection between the hanger and the top mold.

[0017] Optionally, a shift rod is provided on the side wall of the slider, and an end of the shift rod away from the slider passes through the bottom of the second reinforcing transverse plate, and a shift groove for the shift rod to move is provided on the second reinforcing transverse plate.

[0018] Through the above technical solution, the push rod can easily drive the slider to move, and then it is convenient to separate the hanger and the top formwork after the wet joint formwork is removed from the box girder, so as to facilitate the reuse of the wet joint formwork.

[0019] Optionally, the supporting member includes a push plate and a push rod, the push plate is slidably connected to the reinforcing inclined plate along the length direction of the reinforcing inclined plate, the push rod is perpendicular to the reinforcing inclined plate and slidably connected to the reinforcing inclined plate, a second inclined surface is provided on the push plate, and a driving rod is provided on the side wall of the push rod, when the push plate moves toward the bottom mold, the second inclined surface abuts the driving rod and pushes the driving rod to move toward the abdominal mold until the push rod is tightly against the abdominal mold; the top of the push plate is fixedly connected to the driving plate, and the bottom of the threaded section is fixedly connected to a pressure rod, and the pressure rod is used to push the driving plate toward the bottom mold, and when the slider is stuck in the annular groove, the corresponding push rod is tightly against the abdominal mold.

[0020] By adopting the above technical solution, when the threaded section moves downward, it drives the pressure rod to move downward, and the pressure rod applies pressure to the driving plate, so that the push plate moves toward the bottom mold, and the push plate drives the second inclined surface to move, and the second inclined surface pushes the driving rod toward the web mold, thereby making the push rod and the web mold tightly pressed against each other, ensuring that the web mold and the box beam or the closing section fit tightly. At the same time, the driving plate also applies a reaction force to the pressure rod, so that a stable mechanical system is formed between the web mold, the push rod, the push plate, the hanger, the top mold and the positioning plate, thereby improving the overall stability and bearing capacity of the wet joint formwork.

[0021] Optionally, stretch ropes are fixedly connected to the bottom mold and the side molds.

[0022] By adopting the above technical solution, the stretch rope facilitates pulling down the wet joint template as a whole when the wet joint template is disassembled.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. Using strain-hardening UHPC as the casting material can speed up the formation of wet joints and improve the strength after forming, thereby improving construction efficiency and ensuring construction quality. Furthermore, the UHPC mixer mixes the concrete directly on the box girder surface, enabling immediate pouring after mixing. This not only saves transportation time but also ensures that the poured concrete is in the proper state, further ensuring the forming quality. 2. First, use three sets of limiters to fix the two box beams and the closing section respectively. Then connect all three sets of limiters to the positioning frame to achieve the positioning and fixation of the closing section and the box beams on both sides, providing a stable foundation for subsequent construction; 3. The side formwork is hinged to the top formwork to better fit the box girder. At the same time, the lifting ring facilitates the lifting of the wet joint formwork as a whole. The positioning plate can cooperate with the hanging rod to fix the wet joint formwork as a whole between the box girder and the closing section by pulling. 4. The reinforcement plate can strengthen the wet joint formwork, reducing the possibility of the wet joint formwork bending during the hoisting process, which may cause the formwork to fit loosely with the box beam or the closing section. At the same time, the supporting piece can support the web formwork, ensuring that the web formwork and the closing section of the box beam fit tightly, reducing the possibility of concrete leakage. 5. During installation, the boom is passed through the positioning plate, and the threaded section is passed through the connection hole and threadedly connected to the side wall of the connection hole. This allows the operator to complete the installation of the wet joint formwork above the box girder, reducing the risk of high-altitude construction; 6. When the threaded section is threadedly connected to the inner hole of the connecting hole, the threaded section moves downward as a whole, first abutting against the first inclined surface, causing the slider to be pressed back into the slide groove. Then, when the slide groove and the annular groove are aligned in the height direction, the slider pops out under the action of the compression spring and is stuck in the annular groove, realizing secondary fixation between the boom and the top mold and the second reinforcing cross plate. Cooperating with the connection between the threaded section and the inner wall of the connecting hole, a reliable connection between the boom and the top mold is ensured. 7. The lever is convenient for driving the slider to move, so that after the wet joint formwork is removed from the box girder, the hanger and the top formwork can be separated, so as to facilitate the reuse of the wet joint formwork; 8. When the threaded section moves downward, it drives the pressure rod to move downward. The pressure rod applies pressure to the driving plate, causing the push plate to move toward the bottom formwork. The push plate drives the second inclined surface to move, and the second inclined surface pushes the driving rod toward the web formwork, thereby making the push rod and the web formwork tightly pressed together, ensuring that the web formwork and the box beam or the closing section fit closely. At the same time, the driving plate also applies a reaction force to the pressure rod, forming a stable mechanical system between the web formwork, push rod, push plate, hanger, top formwork and positioning plate, thereby improving the overall stability and load-bearing capacity of the wet joint formwork. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram showing the location of the box girder, the closure section and the wet joint in the present invention.

[0025] Figure 2 It is a schematic diagram of the steel tooth ridge in the present invention.

[0026] Figure 3 It is a structural schematic diagram of the wet joint template in the present invention.

[0027] Figure 4 It is a schematic diagram of the cross-section structure of the wet joint template in the present invention.

[0028] Figure 5 yes Figure 4 A partial enlarged view of part A in the middle.

[0029] In the figure, 1, box girder; 11, stopper; 12, positioning frame; 2, closing section; 3, wet joint formwork; 31, bottom formwork; 311, stretch rope; 32, web formwork; 33, top formwork; 34, side formwork; 341, lifting ring; 35, hanging rod; 351, threaded section; 352, pressure rod; 353, locking nut; 354, conical surface; 355, ring groove; 36, positioning plate; 37, first reinforcing transverse plate; 38, reinforcing inclined plate; 381 , push plate; 3811, drive plate; 3812, second inclined surface; 382, ​​push rod; 3821, drive rod; 39, second reinforcing horizontal plate; 391, connecting hole; 392, slide groove; 393, slider; 394, compression spring; 395, first inclined surface; 396, shift rod; 397, shift groove; 4, tension device to prevent concrete temperature stress cracking; 41, steel tooth step; 411, vertical plate; 42, tension screw; 43, tension nut. DETAILED DESCRIPTION

[0030] The present invention will now be described in further detail with reference to the accompanying drawings, which are simplified schematic diagrams that illustrate the basic structure of the present invention in a schematic manner.

[0031] In the description of the present invention, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like, indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. In the description of the present invention, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be broadly understood, for example, to mean fixed, removable, or integral; mechanically or electrically connected; directly or indirectly through an intermediary; or internally connected between two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] Example 1 In a first aspect, the present application discloses a method for rapid closure of wet-jointed UHPC segments of movable beams.

[0033] A mobile segmental beam wet joint UHPC rapid closure construction method, referring to Figure 1 and Figure 2 , including the following steps: S1. Wet joint arrangement: The wet joint is located at the mid-span of the side span, the mid-span of the middle span and both sides of the top of the transition pier of each box girder 1. The length is 8 to 20 cm, and is 10 cm in this embodiment.

[0034] S2. Hoist Closing Segment 2, Install the Tensioning Device to Prevent Concrete Thermal Stress Cracking, Install the Wet Joint Locking Device, and Install the Formwork: The bridge-erecting crane symmetrically assembles the construction segment beams to their maximum cantilever position and then begins hoisting Closing Segment 2. The segment position and elevation are adjusted, and the tensioning device to prevent concrete thermal stress cracking is installed. A temporary positioning device is installed to lock the box girder 1 and closing segment 2 on both sides. Finally, wet joint formwork 3 is installed. To prevent grout leakage, expansion seals are installed at the contact points between the wet joint formwork 3, the box girder 1, and closing segment 2.

[0035] Specifically, the tensioning device 4 for preventing concrete thermal stress cracking includes a steel toothed sill 41 and tensioning screws 42. Two sets of steel toothed sills 41 are bolted or welded to the two box girders 1. Vertical plates 411 are fixedly connected to the steel toothed sill 41. The ends of the tensioning screws 42 pass through the vertical plates 411 of the two steel toothed sills 41 and are threadedly connected to tensioning nuts 43. The tensioning nuts 43 abut the corresponding vertical plates 411 to generate tensioning force, preventing cracking in the wet joint caused by thermal expansion and contraction during concrete pouring. Multiple sets of tensioning devices 4 for preventing concrete thermal stress cracking can be provided along the width of the box girder 1; in this embodiment, two sets are provided.

[0036] S3. Wet Joint Mixing: Strain-hardening UHPC is mixed on the beam surface using a UHPC mixer and then discharged into a 1-cubic-meter casting hopper. Strain-hardening UHPC can utilize the ultra-high-performance calcium-silicon nanocomposite material produced by Zhejiang Hongritai Nike New Material Technology Co., Ltd., combined with the company's specialized specialty fiber TF04C. Field tests have shown that using ultra-high-performance concrete (UHPC) wet joint material achieves a compressive strength of 72 MPa or higher and an elastic modulus of 32 GPa or higher after 36 hours. This meets the requirements after just 36 hours, shortening the construction period by over three days compared to traditional concrete materials.

[0037] S4. Pouring wet joint concrete of closing section 2: Use the overhead crane to lift the pouring hopper to the wet joint for pouring. For locations where the pouring height exceeds two meters, set up a chute on site for discharging the material.

[0038] S5. Formwork removal: After the joint strength of the closed section 2 reaches the concrete strength standard, remove the wet joint formwork 3 and the temporary positioning device.

[0039] By using strain-hardening UHPC as the casting material, the forming speed of wet joints can be increased, and the strength after forming can be improved, which can improve construction efficiency and ensure construction quality. At the same time, the UHPC mixer mixes directly on the surface of box girder 1, and can be poured immediately after mixing, which can not only save transportation time, but also ensure that the poured concrete is in the right state, thereby further ensuring the forming quality.

[0040] Specifically, in step S4, the order of pouring wet joint concrete is to pour the bottom plate first, then pour the belly formwork 32, and finally pour the top plate. The surface of the top plate is roughened and then covered with water for curing.

[0041] In step S2, the wet joint is located between the closing section 2 and the box girder 1. The temporary positioning device includes a positioning skeleton 12 and a limiter 11. The limiter 11 is provided in three groups. The three groups of limiters 11 are fixedly connected to the two box girders 1 and the closing section 2, respectively. The positioning skeleton 12 is fixedly connected to the three groups of limiters 11. The limiters 11 can be fixedly connected to the embedded parts on the box girder 1 or the closing section 2 by bolts, or can be directly welded. The limiters 11 and the positioning skeleton 12 can also be welded or bolted. First, the three groups of limiters 11 are fixedly connected to the two box girders 1 and the closing section 2, respectively. Then, the three groups of limiters 11 are connected to the positioning skeleton 12, thereby achieving the positioning and fixation of the closing section 2 and the box girders 1 on both sides, providing a stable foundation for subsequent construction.

[0042] In step S2, refer to Figures 3 to 5 The wet joint formwork 3 includes, from the center to the sides, a bottom formwork 31, two web forms 32, two top forms 33, and two side forms 34. The side forms 34 are hinged to their adjacent top forms 33, and a lifting ring 341 is connected to the end of the side formwork 34 away from the top formwork 33. The box girder 1 and the closing section 2 are provided with the same set of positioning plates 36. Each set of positioning plates 36 is provided with multiple positioning plates along the width direction of the box girder 1. The positioning plates 36 are located above the wet joint and are connected to the bottom formwork 31 or the top formwork 33 via a hanging rod 35. The side forms 34 are hinged to the top formwork 33 to better fit the box girder 1. At the same time, the lifting ring 341 facilitates the lifting of the wet joint formwork 3 as a whole. The positioning plates 36 can cooperate with the hanging rod 35 to fix the wet joint formwork 3 as a whole between the box girder 1 and the closing section 2 by pulling.

[0043] Furthermore, a reinforcing plate is provided below the wet joint formwork 3. The reinforcing plate includes a first reinforcing transverse plate 37, two reinforcing oblique plates 38, and two second reinforcing transverse plates 39. The first reinforcing transverse plate 37 is fixedly connected to the bottom formwork 31, and the two second reinforcing transverse plates 39 are respectively fixedly connected to the two top formworks 33. The two reinforcing oblique plates 38 are respectively supported against the corresponding web formwork 32 through a set of supporting members. The reinforcing plate can reinforce the wet joint formwork 3, reducing the possibility of the wet joint formwork 3 bending during the hoisting process, resulting in a loose fit between the box girder 1 or the closing section 2. At the same time, the supporting members can support the web formwork 32, ensuring that the web formwork 32 fits tightly with the box girder 1 and the closing section 2, reducing the possibility of concrete leakage. The traditional wet joint formwork 3 adopts a single steel plate integral structure. Due to its long overall length, it is very easy to bend and deform during hoisting, installation, and disassembly, resulting in a large gap between the box girder 1 and the closing section 2.

[0044] Specifically, the second reinforcing cross plate 39 and the top formwork 33 are provided with connecting holes 391 for inserting the suspension rod 35. The connecting holes 391 are provided through both the second reinforcing cross plate 39 and the top formwork 33. The bottom of the suspension rod 35 is provided with a threaded section 351, which is threadedly connected to the inner wall of the connecting hole 391. The top of the suspension rod 35 passes through the positioning plate 36 and is threadedly connected to a locking nut 353. During installation, the suspension rod 35 is passed through the positioning plate 36, and the threaded section 351 is inserted into the connecting hole 391 and threadedly connected to the side wall of the connecting hole 391. This allows the operator to complete the installation of the wet joint formwork 3 from above the box girder 1, reducing the risks of high-altitude construction.

[0045] More specifically, a sliding groove 392 is provided on the side wall of the connecting hole 391, and a slider 393 slides in the sliding groove 392. An annular groove 355 for inserting the slider 393 is provided on the side wall of the threaded section 351. A compression spring 394 is provided in the sliding groove 392, and one end of the compression spring 394 abuts against the end of the slider 393 away from the sliding groove 392, and the other end abuts against the end of the sliding groove 392 away from the annular groove 355. A first inclined surface 395 is provided on the end of the slider 393 facing the sliding groove 392, and the first inclined surface 395 is provided on the side of the slider 393 facing the positioning plate 36. When the threaded section 351 is threadedly connected to the inner hole of the connecting hole 391, the threaded section 351 moves downward as a whole, first abutting against the first inclined surface 395, causing the slider 393 to be pressed back into the slide groove 392, and then when the slide groove 392 and the annular groove 355 are aligned in the height direction, the slider 393 pops out and is stuck in the annular groove 355 under the action of the compression spring 394, realizing secondary fixation between the hanger 35 and the top mold 33 and the second reinforcing cross plate 39, and cooperating with the connection between the threaded section 351 and the inner wall of the connecting hole 391 to ensure a reliable connection between the hanger 35 and the top mold 33.

[0046] In addition, a lever 396 is provided on the side wall of the slider 393. The end of the lever 396, away from the slider 393, extends through the bottom of the second reinforcing transverse plate 39. The second reinforcing transverse plate 39 is provided with a shifting slot 397 for the lever 396 to move. The lever 396 facilitates movement of the slider 393, thereby facilitating separation of the hanger 35 from the top form 33 after the wet joint form 3 is removed from the box girder 1, thereby facilitating reuse of the wet joint form 3.

[0047] It should be noted that the connection structure between the bottom mold 31, the first reinforcing transverse plate 37 and the suspension rod 35 is the same as the connection structure between the top mold 33, the second reinforcing transverse plate 39 and the suspension rod 35, so it will not be repeated here.

[0048] The supporting member includes a push plate 381 and a plurality of push rods 382. The push plate 381 is slidably connected to the reinforcing inclined plate 38 along the length direction of the reinforcing inclined plate 38. The plurality of push rods 382 are arranged in an array along the length direction of the reinforcing inclined plate 38. The push rods 382 are perpendicular to the reinforcing inclined plate 38 and are slidably connected to the reinforcing inclined plate 38. A second inclined surface 3812 is provided on the push plate 381, and a driving rod 3821 is provided on the side wall of the push rod 382. When the push plate 381 moves toward the bottom mold 31, the second inclined surface 3812 abuts against the driving rod 3821 and pushes the driving rod 3821 to move toward the abdominal mold 32 until the push rod 382 abuts against the abdominal mold 32. The top of the push plate 381 is fixedly connected to the driving plate 3811, and the bottom of the threaded section 351 is fixedly connected to the pressure rod 352. The pressure rod 352 is used to push the driving plate 3811 toward the bottom mold 31. When the slider 393 is stuck in the annular groove 355, the corresponding push rod 382 is pressed against the abdominal mold 32. When the threaded section 351 moves downward, it drives the pressure rod 352 to move downward. The pressure rod 352 applies pressure to the driving plate 3811, so that the push plate 381 moves toward the bottom mold 31. The push plate 381 drives the second inclined surface 3812 to move, and the second inclined surface 3812 pushes the driving rod 3821 to move toward the web mold 32, thereby making the top rod 382 press against the web mold 32 to ensure that the web mold 32 is tightly fitted with the box beam 1 or the closing section 2. At the same time, the driving plate 3811 also applies a reaction force to the pressure rod 352, so that a stable mechanical system is formed between the web mold 32, the top rod 382, ​​the push plate 381, the hanger 35, the top mold 33 and the positioning plate 36, thereby improving the overall stability and bearing capacity of the wet joint formwork 3.

[0049] It should be noted that a tapered surface 354 is provided on the pressing rod 352 for easy guidance, and is also biased to cooperate with the first inclined surface 395 to press the slider 393 back into the sliding groove 392.

[0050] In addition, tension ropes 311 are fixedly connected to the bottom formwork 31 and the side formwork 34. The tension ropes 311 facilitate pulling the wet joint formwork 3 downward as a whole when removing the wet joint formwork 3. When removing the wet joint formwork 3, the locking nut 353 above the positioning plate 36 is loosened, and then the wet joint formwork 3 is pulled downward as a whole, separating the wet joint formwork 3 from the box girder 1 and the closing section 2, thereby completing the removal of the wet joint formwork 3.

[0051] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. A mobile segmental beam wet joint UHPC rapid closure construction method, characterized in that: The steps include: S1. Wet joint arrangement: The wet joint is located at the mid-span of the side span, the mid-span of the middle span and both sides of the top of the transition pier of each box girder (1), and its length is 8 to 20 cm; S2, hoisting the closing section (2), installing the tensioning device to prevent concrete temperature stress cracking, installing the wet joint locking device and the template: the bridge erection machine symmetrically hangs the construction segment beam to the maximum hanging state and then starts to hoist the closing section (2), adjust the segment position and elevation, install the tensioning device to prevent concrete temperature stress cracking, install the temporary positioning device to lock the box beams (1) and the closing section (2) on both sides, and then install the wet joint template (3); S3, wet joint mixing: using a UHPC mixer to mix strain hardening UHPC on the beam surface of the box beam (1), and after mixing, discharge the material into a 1 cubic meter casting hopper; S4. Pouring the wet joint concrete of the closing section (2): Use a bridge crane crane to lift the pouring hopper to the wet joint for pouring. For locations where the pouring height exceeds two meters, a chute is set up on site for discharge; S5. Formwork removal: After the joint strength of the closed section (2) reaches the concrete strength standard, the wet joint formwork (3) and the temporary positioning device are removed.

2. The method for rapid closure of wet-jointed UHPC segments according to claim 1 is characterized by: In step S4, the order of pouring wet joint concrete is to pour the bottom plate first, then pour the belly form (32), and finally pour the top plate. The surface of the top plate is roughened and covered with water for maintenance.

3. The method for rapid closure of wet-jointed UHPC segments according to claim 2, characterized in that: In step S2, the wet joint is located between the closing section (2) and the box beam (1), and the temporary positioning device includes a positioning frame (12) and a limiter (11). The limiter (11) is provided in three groups, and the three groups of limiters (11) are fixedly connected to two box beams (1) and one closing section (2) respectively. The positioning frame (12) is fixedly connected to the three groups of limiters (11).

4. The method for rapid closure of wet-jointed UHPC segments according to claim 3 is characterized by: In step S2, the wet joint template (3) includes a bottom template (31), two web templates (32), two top templates (33) and two side templates (34) in sequence from the middle to the two sides, the side templates (34) are hinged to the adjacent top templates (33), and the ends of the side templates (34) away from the top template (33) are connected to a hanging ring (341); The box beam (1) and the folding section (2) are provided with a same set of positioning plates (36), and each set of positioning plates (36) is provided with a plurality of positioning plates along the width direction of the box beam (1). The positioning plates (36) are located above the wet joints, and the positioning plates (36) are connected to the bottom mold (31) or the top mold (33) through a suspension rod (35).

5. The method for rapid closure of wet-jointed UHPC segments according to claim 4 is characterized in that: A reinforcing plate is provided below the wet joint template (3), and the reinforcing plate includes a first reinforcing transverse plate (37), two reinforcing inclined plates (38) and two second reinforcing transverse plates (39). The first reinforcing transverse plate (37) is fixedly connected to the bottom mold (31), and the two second reinforcing transverse plates (39) are respectively fixedly connected to the two top molds (33). The two reinforcing inclined plates (38) are respectively supported against the corresponding abdominal molds (32) through a group of supporting members.

6. The method for rapid closure of wet-jointed UHPC segments according to claim 5, characterized in that: The second reinforcing transverse plate (39) and the top mold (33) are provided with a connecting hole (391) for inserting the suspension rod (35). The connecting hole (391) is set to pass through the second reinforcing transverse plate (39) and the top mold (33). The bottom of the suspension rod (35) is provided with a threaded section (351). The threaded section (351) is threadedly connected to the inner wall of the connecting hole (391). The top of the suspension rod (35) passes through the positioning plate (36) and is threadedly connected to a locking nut (353).

7. The method for rapid closure of wet-jointed UHPC segments according to claim 6, characterized in that: A sliding groove (392) is provided on the side wall of the connecting hole (391), a slider (393) slides in the sliding groove (392), an annular groove (355) for the slider (393) to be inserted is provided on the side wall of the threaded section (351), a compression spring (394) is provided in the sliding groove (392), one end of the compression spring (394) abuts against the end of the slider (393) away from the sliding groove (392), and the other end abuts against the end of the sliding groove (392) away from the annular groove (355), and a first inclined surface (395) is provided on the end of the slider (393) facing the sliding groove (392), and the first inclined surface (395) is provided on the side of the slider (393) facing the positioning plate (36).

8. The method for rapid closure of wet-jointed UHPC segments according to claim 7, characterized in that: A shifting rod (396) is provided on the side wall of the slider (393), and one end of the shifting rod (396) away from the slider (393) passes through the bottom of the second reinforcing transverse plate (39), and a shifting groove (397) for the shifting rod (396) to move is provided on the second reinforcing transverse plate (39).

9. The method for rapid closure of wet-jointed UHPC segments according to claim 7, characterized in that: The supporting member includes a push plate (381) and a push rod (382), wherein the push plate (381) is slidably connected to the reinforcing inclined plate (38) along the length direction of the reinforcing inclined plate (38), and the push rod (382) is perpendicular to the reinforcing inclined plate (38) and slidably connected to the reinforcing inclined plate (38), and a second inclined surface (3812) is provided on the push plate (381), and a driving rod (3821) is provided on the side wall of the push rod (382). When the push plate (381) moves toward the bottom mold (31), the second inclined surface (3812) abuts against the driving rod (3821) and pushes the driving rod (3821) to move toward the abdominal mold (32) until the push rod (382) abuts against the abdominal mold (32); The top of the push plate (381) is fixedly connected to a driving plate (3811), and the bottom of the threaded section (351) is fixedly connected to a pressure rod (352). The pressure rod (352) is used to push the driving plate (3811) toward the bottom mold (31). When the slider (393) is inserted into the annular groove (355), the corresponding push rod (382) is pressed against the abdominal mold (32).

10. The method for rapid closure of wet-jointed UHPC segments according to claim 7, characterized in that: The bottom mold (31) and the side mold (34) are both fixedly connected with a stretching rope (311).

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