A combined formwork system and construction method for UHPC segmental beams

Abstract

A combined formwork system for UHPC segmental beams includes two oppositely arranged side formwork assemblies, a bottom formwork assembly located between the two side formwork assemblies, and an end formwork assembly located in front of the bottom formwork assembly. The tops of the two side formwork assemblies are connected to a top frame. Each side formwork assembly includes a side support frame, with a sliding unit connected to the bottom of the side support frame. The side support frame facing the side formwork assembly is connected to the side formwork via a second tensioning member. The bottom of the side support frame is connected to the bottom formwork assembly via a first tensioning member, and several third tensioning members are connected to the top. Thrust blocks are provided at both ends of the lower crossbeam of the top frame. The two ends of the lower crossbeam are respectively located in openings between the third tensioning members and the side support frames. The thrust blocks are located inside the third tensioning members, with a gap between them. A bolt passes through the thrust blocks and the third tensioning members. This formwork system can reduce the impact of lateral pressure on the formwork and cleverly solves the problem of difficult demolding of high-dimension segmental beams by utilizing the thrust blocks of the top frame.

Description

Technical Field

[0001] This invention relates to the field of segmental beam manufacturing technology, specifically to a combined formwork system and construction method for UHPC segmental beams. Background Technology

[0002] Ultra-high performance concrete (UHPC) is widely used in bridge engineering. The traditional method of use is a steel-UHPC combination, in which the steel main beam and the concrete bridge deck are an integral structure with an inverted trapezoidal shape, as shown in patent application number: CN202511526781.2.

[0003] Ultra-high performance concrete (UHPC) – steel box girder composite continuous bridge, as a novel composite structure, is beginning to be applied in bridge construction, especially in the construction of long-span bridges, fully utilizing the tensile strength of steel and the compressive strength of concrete. For example, patent application number CN202510996323.9, entitled "Welding Construction Device and Construction Process for UHPC-Steel Box Composite Continuous Bridge," demonstrates such a structure. In this design, the UHPC beam is an ultra-large U-shaped channel beam, comprising several segmental beams, with a single segment elevation ranging from 2.25m to 6.8m. Because this UHPC beam is a world-first ultra-heavy, irregularly shaped structural beam, a specially designed formwork system is required for its production, and the demolding problem of high-elevation UHPC beams must be addressed. Summary of the Invention

[0004] To address the technical problems existing in the background art, the present invention provides a combined formwork system and construction method for UHPC segmental beams.

[0005] The technical solution of this invention is as follows: A combined formwork system for UHPC segmental beams includes two side formwork components arranged opposite each other, a bottom formwork component is provided at the lower part between the two side formwork components, an end formwork component is provided in front of the bottom formwork component, and the tops of the two side formwork components are connected to the top frame.

[0006] The side mold assembly includes a side support frame. The bottom of the side support frame is connected to a sliding unit, which can slide left and right. The side support frame facing the bottom mold assembly is connected to the side template through a second tensioner. The bottom of the side support frame is connected to the bottom mold assembly through a first tensioner. Several third tensioners are connected to the top. An open slot structure is formed between the third tensioners and the side support frame.

[0007] The top frame includes several lower crossbeams arranged horizontally at the bottom. Thrust blocks are provided at both ends of the lower crossbeams. The two ends of the lower crossbeams are respectively located in the opening slots between the third tension member and the side support frame. The thrust blocks are located inside the third tension member and a gap is left between them. A screw rod passes through the thrust block and the third tension member, and the two ends of the screw rod are fixed with nuts. It also includes an inner mold assembly, located inside the U-shaped frame formed by the side mold assembly and the bottom mold assembly.

[0008] The side formwork assembly and bottom formwork assembly of this invention form a U-shaped frame to accommodate UHPC segmental beams with special shapes. For ultra-large UHPC segmental beams, compared to ordinary concrete, the pouring process generates extremely high lateral pressure. The side formwork of this invention is a vertical formwork, with its sides connected to the side support frame via a second tension member. To facilitate demolding, the lower end of the side support frame is connected to a sliding unit. However, the sliding unit lacks the capacity to withstand such high lateral pressure. Therefore, a first tension member at the bottom is designed to connect the side support frame to the bottom formwork assembly, transferring part of the lateral pressure on the lower half of the side formwork to the bottom formwork assembly. A third tension member at the top connects the side support frame to the top frame, transferring part of the lateral pressure on the upper half of the side formwork to the top frame. This prevents the side formwork assembly from deforming due to the enormous lateral pressure during pouring, thus preventing any impact on the quality of the segmental beam.

[0009] To further address the demolding issue of the side formwork, longitudinal beams are connected between adjacent lower crossbeams of the top frame, and mounting bases are connected to the top of the side support frame. Telescopic cylinders are installed on the mounting bases, and the rods of the telescopic cylinders can abut against the adjacent longitudinal beams.

[0010] Because the sliding unit is located at the lower end of the side support frame, the force acting on the top of the side formwork is relatively small, making it difficult for the top to separate from the poured segmental beam. Therefore, a telescopic cylinder is added between the top frame and the top of the side support frame. The reaction force of the telescopic cylinder is used to push the top of the side formwork to separate from the segmental beam. Since there are two side formwork assemblies, in actual operation, sometimes one side of the side formwork has separated, but the other side has not yet separated. Continuing to push the telescopic cylinder outward will only push the top frame to one side, making the opening on the separated side larger. At this time, the telescopic rod of the telescopic cylinder on the separated side can be retracted using the gap reserved between the thrust block of the top frame and the third tensioning member. Only the telescopic rod of the telescopic cylinder on the unseparated side is controlled to push the top frame to move, so that the thrust block of the top frame and the third tensioning member on the separated side come into contact, making the two form a whole. After that, if the telescopic cylinder continues to extend outward, it will be affected by the reaction force of the other side formwork assembly, which can accelerate the separation of the unseparated side formwork from the segmental beam.

[0011] Preferably, the side mold assembly further includes a fixed platform, and the sliding unit is located on the upper surface of the fixed platform. Several support members are fixed to the end of the fixed platform away from the bottom mold assembly, and the bottom of the side support frame is connected to the support members at the end away from the bottom mold assembly to prevent the side support frame from sliding due to lateral pressure during the pouring process.

[0012] In one embodiment, the side support frame is a triangular frame structure, specifically a right-angled triangular frame structure, including several horizontal braces, vertical braces, diagonal braces and internal reinforcing braces, and longitudinal braces connecting adjacent horizontal braces, vertical braces and diagonal braces.

[0013] Furthermore, the side support frame is higher than the side formwork to facilitate connection to the top frame. A workbench is provided on the outer side of the top, and an auxiliary ladder can be installed on the outer side of the side support frame to facilitate workers' access to the workbench.

[0014] In one embodiment, the third tensioning member includes an L-shaped side brace connected to one side of the top of the side support frame and parallel to the side template. The lower parts of the left and right sides of the side brace are provided with reinforcing plates connected to the side support frame. Through holes are opened on the reinforcing plates and the thrust block for the connecting rod to pass through.

[0015] As one embodiment, the side template is provided with several longitudinal braces on the side facing the side support frame, and the longitudinal braces include U-shaped connectors; The second tensioning component includes an outer clamp, which is clamped on the side of the vertical support of the side support frame away from the side template. A screw is threaded through the outer clamp, and one end of the screw is connected to a hook. The hook includes an upper downward hook and a lower straight support plate. The hook can clamp the longitudinal support, and the other end of the screw is provided with a locking nut.

[0016] In one embodiment, the first tensioning member includes a diagonal tie rod, and a tensioning seat is provided on one side of the bottom mold assembly. One end of the diagonal tie rod is connected to the tensioning seat, and the other end is inclined upward and connected to the side support frame.

[0017] In one embodiment, the sliding unit includes a sliding seat on which a sliding frame is slidably connected. Both ends of the sliding frame are hinged to elastic connectors, which are elastically connected to the lower end of the side support frame. It also includes a telescopic cylinder for driving the sliding frame to move.

[0018] This invention also provides a construction method for a combined formwork system for UHPC segmental beams, using the aforementioned combined formwork system, with the following specific steps: Step 1: Template system assembly; Transport the bottom mold assembly corresponding to the segment beam to be produced to the two side mold assemblies, and transport the formed segment beam adjacent to the segment beam to be produced and its corresponding bottom mold assembly to its rear end and align them. The drive side support frame moves toward the bottom mold assembly under the action of the sliding unit, and makes the side template flush with the outer wall of the forming segment beam; Connect the end mold assembly to the side mold assembly and the bottom mold assembly; Fix both ends of the top frame to the top of the side support frame; Hoist the steel reinforcement cage and install the inner formwork components; Step two: Cast the segmental beams; Step 3, exit the template; Release the first, second, and third tensioners on the side formwork assembly, drive the telescopic cylinder at the top of the side support frame to push it toward the top frame, and use the reaction force to push the upper part of the side support frame to separate from the poured segment beam; If only one side formwork assembly separates, the telescopic cylinder on the separated side retracts, and the telescopic cylinder on the unseparated side pushes the top frame alone, causing the thrust block at the bottom of the top frame to abut against the third tensioning member of the side formwork assembly on the separated side, and the telescopic cylinder continues to move until the side formwork assembly on the unseparated side separates from the cast segment beam. Drive the sliding unit to separate the lower part of the side support frame from the cast segment beam; Disconnect the inner formwork assembly and end formwork assembly from the poured segmental beam; The bottom formwork assembly, along with the poured segmental beams, is moved out along the track by a transfer vehicle.

[0019] Through the above design, this invention provides a combined formwork system and construction method for UHPC segmental beams. It utilizes a special combined formwork system designed for short-line construction of the unique U-shaped UHPC segmental beams. Addressing the issue of excessive lateral pressure on high-sized UHPCs, numerous tensioning components are designed into the combined structure of the side formwork assembly, bottom formwork assembly, and top frame to reduce the impact of lateral pressure on the formwork. Furthermore, the use of thrust blocks on the top frame cleverly solves the problem of difficult demolding of high-sized segmental beams. Attached Figure Description

[0020] In the attached diagram: Figure 1 A three-dimensional view of the modular template system; Figure 2 This is a schematic diagram showing the connection between the side mold assembly and the top frame; Figure 3 for Figure 2 A magnified view of the central X position; Figure 4 for Figure 2 Enlarged view of the Y-position in the middle; Figure 5 This is the front view of the modular template system; Figure 6 This is a schematic diagram of the side mold assembly. Figure 7 This is a schematic diagram of the sliding element structure; Figure 8 for Figure 6 A magnified view of the Z-position in the middle; Figure 9 This is a schematic diagram of the second tensioning component; Figure 10 This is a schematic diagram of the top frame structure; Figure 11 This is a schematic diagram of the bottom mold assembly. Figure 12 This is a schematic diagram of the end-mold assembly. Figure 13 for Figure 12A magnified view of the area at position W in the middle; Figure 14 This is a top view of the end-mold assembly; Figure 15 This is a schematic diagram of the internal mold assembly. Figure 16 This is a sectional view of the inner mold assembly; Figure 17 for Figure 16 A magnified view of the middle V position; The components represented by the various reference numerals in the diagram are: 1. Side mold assembly; 11. Side support frame; 111. Horizontal brace; 112. Vertical brace; 113. Diagonal brace; 114. Longitudinal brace; 115. Mounting base; 12. Side template; 13. Sliding unit; 131. Sliding seat; 132. Sliding frame; 1321. Clamping plate; 133. Elastic connector; 1331. Butterfly spring; 134. First hydraulic cylinder; 14. Fixed platform; 15. Support component; 16. First tensioning component; 17. Second tensioning component; 171. External clamp; 172. Hook; 173. Reinforcing plate; 18. Third tensioning component; 181. Side brace; 182. Reinforcing plate; 183. Connecting rod; 19. Workbench; 2. Top frame; 21. Lower crossbeam; 22. Longitudinal beam; 23. Thrust block; 24. Hanging plate; 25. Second hydraulic cylinder; 3. Bottom mold assembly; 31. Bottom support frame; 311. Fixed support leg; 312. Movable support leg; 313. Tensioning seat; 32. Bottom template; 321. End mold connecting frame; 4. End mold assembly; 41. Fixed frame; 42. Vertical frame; 43. Horizontal frame; 44. Adjusting rod; 45. Fixing component; 46. Side end mold; 47. Bottom end mold; 5. Inner mold assembly; 51. Pressure plate; 52. Intermediate beam; 53. Top beam; 54. Connecting seat; 55. Lower cover; 56. Elastic pad. Detailed Implementation

[0021] Example 1 See Figure 1 and Figure 5UHPC (Ultra-High Performance Concrete) is mainly composed of steel fibers, silica fume, and quartz powder. It utilizes the maximum bulk density theory to optimize particle size distribution, resulting in a low water-cement ratio (0.15-0.25) and the absence of coarse aggregate. Its compressive strength can reach over 400 MPa. This embodiment primarily addresses two main issues: first, how to fabricate multiple segments of UHPC with a limited number of modular formwork systems, given that each segment has the same shape but different heights; and second, how to design a modular formwork system specifically for UHPC segments, which remain in a fluid state during pouring and require 9-10 hours for initial setting, exhibiting increasing outward expansion on the sides that could damage the side formwork, and significant buoyancy on the bottom that could damage the bottom formwork.

[0022] Specifically, the combined template system of this embodiment includes two side mold components 1 arranged opposite to each other, a bottom mold component 3 is provided at the lower part between the two side mold components 1, an end mold component 4 is provided in front of the bottom mold component 3, and the tops of the two side mold components 1 are connected to the top frame 2.

[0023] The side mold assembly 1 includes a side support frame 11. The bottom of the side support frame 11 is connected to a sliding unit 13, which can slide left and right. The side support frame 11 facing the bottom mold assembly 3 is connected to the side template 12 through a second tensioner 17. The bottom of the side support frame 11 is connected to the bottom mold assembly 3 through a first tensioner 16. The top is connected to several third tensioners 18, and an opening groove structure is formed between the third tensioners 18 and the side support frame 11.

[0024] The top frame 2 includes several lower crossbeams 21 arranged horizontally at the bottom. Thrust blocks 23 are provided at both ends of the lower crossbeams 21. The two ends of the lower crossbeams 21 are respectively located in the opening slots between the third tension member 18 and the side support frame 11. The thrust blocks 23 are located inside the third tension member 18 and a gap is left between them. A screw is passed between the thrust blocks 23 and the third tension member 18, and the two ends of the screw are fixed with nuts.

[0025] It also includes an inner mold component 5, located inside the U-shaped frame formed by the side mold component 1 and the bottom mold component 3.

[0026] The side formwork assembly 1 and the bottom formwork assembly 3 of this invention form a U-shaped frame to accommodate UHPC segmental beams with special shapes. For ultra-large UHPC segmental beams, compared to ordinary concrete, the pouring process generates extremely high lateral pressure. The side formwork 12 of this invention is a vertical formwork, with its side connected to the side support frame 11 via a second tensioner 17. To facilitate demolding, the lower end of the side support frame 11 is connected to the sliding unit 13. The sliding unit 13 does not have the capacity to withstand such high lateral pressure. Therefore, a first tensioner 16 at the bottom is designed to connect the side support frame 11 to the bottom formwork assembly 3, transferring part of the lateral pressure on the lower half of the side formwork 12 to the bottom formwork assembly 3. A third tensioner 18 at the top connects the side support frame 11 to the top frame 2, transferring part of the lateral pressure on the upper half of the side formwork 12 to the top frame 2. This prevents the side formwork assembly 1 from deforming due to the enormous lateral pressure during pouring, thus preventing any impact on the quality of the segmental beam.

[0027] See below. Figure 11 Let's introduce the bottom formwork assembly 3. The bottom formwork assembly 3 includes a lower bottom support frame 31 and an upper bottom formwork 32. The bottom support frame 31 is a rectangular frame with fixed legs 311 at each of the four lower corners and two movable legs 312 in the middle. The heights of the fixed legs 311 and movable legs 312 are adjustable. The bottom formwork assembly 3 is transported along a ground rail by a transfer vehicle. During transport, the two movable legs 312 are first disassembled to facilitate the transfer vehicle's access to the underside of the bottom support frame 31. During pouring, the transfer vehicle is moved separately, and the two movable legs 312 can be assembled into the underside of the bottom support frame 31 for better support.

[0028] The transfer vehicle includes wheels at the bottom, a rotating shaft in the middle, several telescopic cylinders at the top to lift the bottom mold assembly 3, and several telescopic cylinders around the perimeter to drive the upper part of the transfer vehicle to rotate around the central rotating shaft. After the bottom mold assembly 3 is transported to its position, its position can be fine-tuned.

[0029] The bottom support frame 31 has several tension seats 313 on its side for connecting the first tension member 16.

[0030] Since the adjacent beam segments have varying heights, their top surfaces are flat for overlapping with the steel box, and their bottom surfaces are sloped. Therefore, the upper surface of the bottom formwork 32 is a slope with the same angle. An end formwork connecting frame 321 is detachably connected along the length of one side of the bottom formwork 32 to connect the end formwork assembly 4, and can be removed after pouring.

[0031] Preferably, when producing several segment beams, the middle segment beam with the highest height is first made using the long-line method, and then the remaining segment beams are made using the short-line method. Therefore, the end formwork connecting frame 321 is located on the side with the higher height of the bottom formwork 32.

[0032] The following is a combination of... Figures 5-9 Let's introduce the specific structure of the side mold assembly 1.

[0033] The side formwork assembly 1 includes a fixed platform 14, which is made of concrete and is lower than the bottom formwork assembly 3. The fixed platform 14 is used to support the sliding unit 13, which supports and can push the side support frame 11 to move.

[0034] In this embodiment, the side support frame 11 is a triangular frame structure, specifically a right-angled triangular frame structure, including several horizontal braces 111, vertical braces 112, diagonal braces 113, and internal reinforcing braces. A longitudinal brace 114 connects adjacent horizontal braces 111, vertical braces 112, and diagonal braces 113. The side template 12 is vertically connected to one side of the vertical brace 112. In this embodiment, there are four horizontal braces 111, four vertical braces 112, and four diagonal braces 113, arranged in parallel. See [reference needed]. Figure 1 As shown. The structure of the horizontal brace 111, vertical brace 112, diagonal brace 113 and longitudinal brace 114 adopts an I-shaped structure composed of double channel steel connected back to back.

[0035] Furthermore, the side support frame 11 is higher than the side template 12, with both its top and bottom ends extending beyond the side template 12. The outer side of the extended top portion is connected to a third tensioning member 18 for easy connection to the top frame 2. A workbench 19 is provided on the outer side of the top portion. To facilitate workers' access to the workbench 19, an auxiliary ladder can also be provided on the outer side of the side support frame 11.

[0036] Since the UHPC segmental beams targeted by this invention consist of several segments with the same bottom slope and the same height difference between adjacent segments, manufacturing separate side mold assemblies 1 would be too costly and would also occupy storage space. Therefore, the side support frame 11 of this invention adopts a multi-layer bolted structure. Except for the bottom layer, which requires a large support frame and a connection structure with the first tensioning member 16 and the sliding unit 13, and the top layer, which requires the installation of the workbench 19, the middle layers are divided into several layers according to the height difference between adjacent segments. Correspondingly, the side mold 12 is also designed as a multi-layer bolted structure, just like the side support frame 11. In this way, when producing the segmental beam with the highest height, all layers are used to form the side support frame 11. When producing other heights, the excess layers are removed from top to bottom, reducing the cost of manufacturing the side mold assembly 1. Only one set of side mold assembly 1 is needed to produce all types of UHPC segmental beams.

[0037] Moreover, when assembling the side mold assembly 1, the side support frame 11 and the side template 12 can be bolted together layer by layer from bottom to top, which reduces the assembly difficulty.

[0038] See Figure 7The sliding unit 13 is located on the upper surface of the fixed platform 14 and includes a lower sliding seat 131 and an upper sliding frame 132 that are slidably connected. There are two sliding seats 131, which are arranged laterally on the fixed platform 14 and a connecting frame is provided in the middle. There are two sliding frames 132, which are provided in the middle. Each sliding frame 132 is secured to the upper part of the sliding seat 131 by several lower inwardly extending clamping plates 1321 at both ends to prevent the sliding frame 132 from falling off. The upper part of the sliding seat 131 is a flat plate structure with a gap between it and the clamping plates 1321.

[0039] The sliding frame 132 is hinged at both ends with elastic connectors 133, which are elastically connected to the cross brace 111 at the lower end of the side support frame 11. In this embodiment, the elastic connector 133 includes an inverted U-shaped hinge seat at the lower part, which is used to hinge the sliding frame 132 to both ends via a rotating shaft. A threaded rod is connected above the hinge seat, with nuts at both ends and a butterfly spring 1331 in the middle. When connected to the cross brace 111, the butterfly spring 1331 is located at the lower part of the cross brace 111, and the upper end of the threaded rod passes vertically through the cross brace 111 and is locked by the nut. By using the butterfly spring 1331, errors caused by unsuitable pouring height of the fixed platform 14 can be eliminated, and the vibration force of the attached vibrator installed on the side template 12 can be reduced, thus reducing the impact on the fixed platform 14.

[0040] The movement of the sliding frame 132 is accomplished by a telescopic cylinder, specifically a first hydraulic cylinder 134, which is laterally connected between the sliding seat and the connecting frame of the sliding frame. When the first hydraulic cylinder 134 laterally pushes the sliding frame 131 to move, the sliding frame drives the side support frame 11 to move through the elastic connector 133.

[0041] To facilitate easier separation of the side template 12 from the segmental beam during demolding, the sliding seat 131 is designed as a 5-degree wedge-shaped sliding seat, with the end near the bottom mold assembly 3 being higher than the other end. The sliding frame 132 has the same tilt angle. Thus, during demolding, the gravity of the side support frame 11 can be used to make the side template 12 easier to separate.

[0042] Furthermore, in addition to using the sliding unit 13 to elastically support the side support frame 11, a fixed support structure is also needed to support the side support frame 11. In this embodiment, several support members 15 are fixed at the end of the fixed platform 14 away from the bottom mold assembly 3, and the end of the bottom cross brace 111 of the side support frame 11 away from the bottom mold assembly 3 is connected to the support member 15. The support member 15 includes a threaded steel bar vertically fixed on the fixed platform 14, and its upper end passes through the cross brace 111 and is locked by a nut. In this way, the far end of the side support frame 11 is supported, which can prevent the side support frame 11 from sliding due to lateral pressure during the casting process. When demolding, the nuts of the support members 15 need to be loosened appropriately to accommodate the change in the slope of the sliding seat 131.

[0043] The sliding unit 13 and the support member 15 alone are not enough to support the side support frame 11 and the side template 12 to resist the lateral pressure borne by the side template 12. Therefore, a first tensioning member 16 is also provided on the side support frame 11 near the bottom mold assembly 3 to convert the lateral pressure into internal force.

[0044] The following is combined with Figure 8 In this embodiment, the first tensioning member 16 includes a diagonal tie rod. An inclined reinforcing brace is provided between the horizontal brace 111 and the vertical brace 112 near the bottom mold assembly 3 on the side support frame 11. A longitudinal brace 114 is fixed above the four reinforcing braces. The diagonal tie rod passes through the longitudinal brace 114 and is connected to the tensioning seat 313 on one side of the bottom mold assembly 3. The connection end of the diagonal tie rod and the tensioning seat 313 is designed in the shape of a hook, and a nut and a pressure plate are provided at the connection end with the side support frame 11.

[0045] Regarding the connection between the side support frame 11 and the side template 12, the side template 12 consists of a vertically arranged pressure plate and a longitudinal brace 114 fixed on one side. The two channel steels of the longitudinal brace 114 are arranged vertically. Due to the high height of the large-size segmental beam, bolting the side support frame 11 and the side template 12 with bolt holes is prone to failure due to drilling errors, and this method is also inefficient. This invention uses a second tensioning member 17 that is easy to disassemble to connect the two.

[0046] The second tensioning member 17 includes an outer clamping member 171 in the shape of a channel steel. The outer clamping member 171 is clamped on the side of the vertical support 112 of the side support frame 11 away from the side template 12, with its opening facing the side template 12. A screw rod is inserted through the center of the outer clamping member 171, and one end of the screw rod is connected to a hook head 172. The hook head 172 includes an upper lower bent hook and a lower straight support plate. The lower bent hook is used to clamp the outer edge of the upper channel steel of the longitudinal support 114, and the straight support plate is used to insert between the two channel steels of the longitudinal support 114 and support the upper channel steel. See details. Figure 8 As shown. During installation, first tilt the hook 172 through the gap in the middle of the vertical support 112 so that the upper part of the hook 172 is locked inside the longitudinal support 114 of the side template 12. Then rotate the second tensioning member 17 until the lower part of the hook extends to the bottom of the upper channel steel of the longitudinal support 114. Finally, tighten the nut at the other end of the screw to tighten the side template 12 onto the vertical support 112. In this way, there is no need to consider the machining error of the side template 12, which facilitates the connection between the side support frame 11 and the side template 12.

[0047] Preferably, a reinforcing plate 173 may be vertically provided on the inner side of the outer clamp 171 to further improve the connection strength between the second tensioning member 17 and the vertical support 114.

[0048] As a further preferred option, in addition to using the second tensioner 17 to laterally tension the side template 12, a support assembly can also be bolted to one side of the vertical brace 112, see [reference]. Figure 8As shown, one end of the lower support component is connected to the side of the vertical support 112, and the other end is connected to the vertical clamping member. The top of the vertical clamping member can press against the inner bottom surface of the lower channel steel of the longitudinal support 114 on the back of the side template 12.

[0049] By means of several second tensioning members 17 and lower support assembly connected to the vertical support 112, the side template 12 can be tightened onto the side support frame 21 to prevent it from sinking.

[0050] Regarding the connection of the top frame 2 to the side support frame 11, please refer to [the relevant documentation]. Figure 10 Let's examine the structure of the top frame 2. In this embodiment, the top frame 2 includes two sets of trapezoidal frames, one at the front and one at the back. The bottom of each trapezoidal frame is a lower crossbeam 21, the length of which is greater than the distance between the tops of the two side formwork components 1. Several longitudinal beams 22 are connected between the tops of the two sets of trapezoidal frames and between the lower crossbeams 21. Several hanging plates 24 are also provided between the thrust blocks 23 at both ends of the lower crossbeams 21. The hanging plates 24 have round holes for hoisting the reinforcing steel skeleton.

[0051] In this embodiment, the thrust block 23 includes two vertical plates perpendicular to the bottom of the lower crossbeam 21. The vertical plates have openings, and several reinforcing ribs are welded between the two vertical plates, with the reinforcing ribs positioned away from the axis of the openings.

[0052] See Figure 4 The third tensioning component 18 includes an L-shaped side brace 181. The side brace 181 is constructed using a double-channel steel open-end butt-welded method to improve its strength. The side brace 181 is connected to one side of the top of the side support frame 11, and its lower horizontal section is connected to the vertical support 112 of the side support frame 11. The left and right outer surfaces of the side brace 181 are parallel to the side template 12. Reinforcing plates 182 are also provided on the lower parts of the left and right sides of the side brace 181, connecting to the vertical support 112 of the side support frame 11. Through holes are provided on both the reinforcing plates 182 and the thrust block 23 for the connecting rod 183 to pass through. After screwing nuts into both ends of the connecting rod 183, the top of the side support frame 11 can be fixed to the top frame 2.

[0053] Furthermore, the distance between the vertical support 112 and the vertical supports 112 on both sides of the side support frame 11 is greater than the width of the lower crossbeam 21. The lower surface of the lower crossbeam 21 is located on the upper surface of the reinforcing plate 182, and the length of the lower crossbeam 21 is greater than the length of the processed segment beam, so that when the upper end of the side template 12 is demolded, the lower crossbeam 21 is still located on the third tensioner 18.

[0054] To further address the demolding issue of the side formwork 12, longitudinal beams 22 are vertically connected between adjacent lower crossbeams of the top frame 2. The vertical supports 112 at the top of the side support frame 11 are all connected to a horizontal mounting base 115 on the side facing the bottom formwork assembly 3. The length of the mounting base 115 is less than the length of the longitudinal beam 22, so that it does not hinder the lateral movement of the top frame 2. A telescopic cylinder is installed on the side away from the vertical support 112. Specifically, the telescopic cylinder is a second hydraulic cylinder 25. The rod head of the second hydraulic cylinder 25 can horizontally abut against the adjacent longitudinal beam 22.

[0055] Because the sliding unit 13 is located at the lower end of the side support frame 11, the force acting on the top of the side formwork 12 is relatively small, making it difficult for the top to separate from the poured segmental beam. Therefore, a second hydraulic cylinder 25 is added between the top frame 2 and the top of the side support frame 11. First, the locking of the connecting rod 183 is released, and then the reaction force of the second hydraulic cylinder 25 is used to push the top of the side formwork 12 to separate from the segmental beam. Since there are two side formwork assemblies 1, in actual operation, sometimes one side of the side formwork 12 has separated, but the other side has not yet separated. Continuing to control the telescopic cylinder to push outward will only push the top frame 2 to one side, making the opening on the separated side larger. At this point, the telescopic rod of the second hydraulic cylinder 25 on the separation side can be retracted by utilizing the gap reserved between the thrust block 23 of the top frame 2 and the third tensioning member 18 on the separation side. Only the telescopic rod of the second hydraulic cylinder 25 on the non-separated side is controlled to push the top frame 2 to move, so that the thrust block 23 of the top frame 2 and the side reinforcing plate 182 of the third tensioning member 18 on the separation side come into contact, so that the two form an integral structure that abuts together. After that, if the second hydraulic cylinder 25 continues to extend outward, it will be affected by the reaction force of the side mold assembly 1 on the other side, which can accelerate the separation of the side mold 12 on the non-separated side from the segment beam.

[0056] Example 2 The following is combined with Figures 12-15 This section will introduce the specific connection structure between the end mold assembly 4 and the side mold assembly 1 and the bottom mold assembly 3.

[0057] This invention primarily targets U-shaped UHPC segmental beams. Therefore, the end mold assembly 4 includes side end molds 46 on both sides and a bottom end mold 47 at the bottom, with specific shapes adapted to the end face shape of the segmental beam. Both the side end molds 46 and the bottom end mold 47 are detachably connected to the fixing frame 41. The end mold assembly 4 is located in front of the side mold assembly 1, and after the side mold assembly 1 is moved into place, it can push the side end molds 46 and the bottom end mold 47 to abut against and connect with the side template 12 and the bottom template 32. The end mold assembly 4 is not needed behind the side mold assembly 1; instead, the size and shape of the segmental beam to be manufactured are positioned using the already formed adjacent segmental beams.

[0058] The bottom mold 47 is laterally bolted to the end mold connecting frame 321 on the high-end extension of the bottom mold assembly 3. The end mold connecting frame 321 can be a U-shaped structure with the opening facing downwards, which facilitates manual assembly of the nut.

[0059] In this embodiment, the fixing frame 41 stands on the ground, and its height matches the height of the highest segment beam when it is made on the bottom mold assembly 1. One fixing frame 41 can be used to connect the side end mold 46 and bottom end mold 47 corresponding to each segment beam, so as to reduce the cost of making several end mold assemblies 3.

[0060] The connection between the fixed frame 41 and the side mold 46 and bottom mold 47 is a combination of the fixed frame 41 and the movable side mold 46 and bottom mold 47. Vertical frames 42 and horizontal frames 43 are movably connected to the sides and bottom of the fixed frame 41, respectively.

[0061] In one embodiment, both the vertical frame 42 and the horizontal frame 43 are I-shaped structures composed of double channel steel with a gap in the middle. A horizontal adjusting rod 44 is welded at the gap. The adjusting rod 44 can be a lead screw, one end of which passes through the fixed frame 41 and is fixed with a nut. By using the adjusting rod 44, the extension distance of the vertical frame 42 and the horizontal frame 43 can be manually adjusted.

[0062] Regarding the support of the vertical frame 42 and the horizontal frame 43, several fasteners 45 are fixed on the vertical frame 42 and the horizontal frame 43 and bolted to the fixed frame 41. The fasteners 45 can be channel steel parts with elongated holes along their upper length. They can be connected to the fixed frame 41 by inserting screws. This makes it easy to adjust the relative position of the vertical frame 42 and the horizontal frame 43 with the fixed frame 41, and can also achieve stable support after tightening.

[0063] The side end mold 46 and the bottom end mold 47 are arranged perpendicular to the side template 12. The shape of the side facing the bottom mold assembly 1 is adapted to the shape of the segment beam end face. In order to achieve quick disassembly, the bolt connection between the vertical frame 42 and the side end mold 46, and between the horizontal frame 43 and the bottom end mold 47, is also abandoned. Instead, a connecting component is provided. Specifically, the style of the second tensioning member 17 can be adopted. It can be used in both the forward and reverse directions. Several channel steels are provided on the side end mold 46 and the bottom end mold 47 to facilitate the tightening of the hook 273 of the second tensioning member 27.

[0064] Since segmental beams come in various models and adjacent segmental beams are connected by a concave-convex interlocking structure, the side end mold 46 and bottom end mold 47 need to be designed with not only bosses but also damping grooves on the other side. Thus, it is necessary to manufacture side end molds 46 of various heights. To address this, the present invention combines the traditional fixed end mold and movable end mold structures. The side end mold 46 and bottom end mold 47 are not directly connected to the fixed frame 41, but are first quickly connected to the vertical frame 42 and the horizontal frame 43 through the second tensioning member 17. The vertical frame 42 and the horizontal frame 43 are detachably connected to the fixed frame 41 through the adjusting rod 44. However, the UHPC segmental beam will generate a large external tension during casting, which cannot be supported by the adjusting rod 44 alone. Therefore, after the vertical frame 42 and the horizontal frame 43 are adjusted into place by the adjusting rod 44, the fixing member 45 is then fastened to the fixed frame 41. Through the above interlocking design, only one set of fixing frame 41, vertical frame 42, and horizontal frame 43 needs to be manufactured to accommodate various models of side end molds 46 and bottom end molds 47, saving on the manufacturing cost of end mold assembly 3. Moreover, the side end mold 46 and bottom end mold 47 are connected by a second tensioning member 17, which facilitates loading and unloading and improves work efficiency.

[0065] To further improve work efficiency, the fixing frame 41 of this invention can be connected to the side end mold 46 and the bottom end mold 47 on both sides respectively, and two sets of bottom mold components 1 are arranged on both sides to produce two segment beams simultaneously. See [link to relevant documentation]. Figure 12 and Figure 14 As shown.

[0066] The remaining technical features of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0067] Example 3 The following is combined with Figures 15-17 Let's introduce the specific connection structure between the inner mold assembly 5 and the bottom mold assembly 3 and the end mold assembly 4.

[0068] The inner mold assembly 5 mainly fits the internal structure of the segmental beam. After the bottom mold assembly 3, side mold assembly 1, and end mold assembly 4 are assembled and the reinforcing steel cage is placed, the inner mold assembly 5 can be installed. It is connected to the bottom mold assembly 3 and side mold assembly 1 by inserting precision-rolled threaded steel bars, and to the end mold assembly 4 by bolting. In this embodiment, the UHPC segmental beam is U-shaped with a reinforcing rib plate in the middle.

[0069] In this embodiment, the inner mold assembly 5 includes a pressure plate 51, an intermediate beam 52, and a top beam 53.

[0070] The pressure plate 51 is attached to the outer surface of the steel reinforcement cage, and several L-shaped intermediate beams 52 perpendicular to the ribs are connected to it. A top beam 53 arranged parallel to the ribs is placed above the intermediate beams 52. Both the intermediate beams 52 and the top beam 53 are I-shaped structures composed of double channel steel with a gap in the middle. After the top beam 53 is placed in place, a precision rolled threaded steel bar is inserted through the middle gap. The threaded steel bar passes through the top beam 53, intermediate beams 52, pressure plate 51, and steel reinforcement cage in sequence and is then connected and fixed to the bottom formwork assembly 3.

[0071] Furthermore, since the bottom surface of the segmental beams used in the bridge is inclined, the pressure plate 51 and the intermediate beam 52 are also arranged at an inclination. In order to facilitate the placement of the top beam 53, several docking seats 54 are also provided above the intermediate beam 52. The lower surface of the docking seat 54 is inclined and fits the intermediate beam 52, while the upper surface is flat to facilitate the placement of the top beam 53. An elongated hole is opened in the middle to facilitate the insertion of precision rolled threaded steel.

[0072] Furthermore, the pressure plate 51 on the side closest to the already formed segment beam presses against the inner upper surface of the adjacent already formed segment beam, forming a sealing structure with the help of the end face of the already formed segment beam. Preferably, the outward extension distance of the pressure plate 51 is about 8cm-10cm.

[0073] As a further preferred option, the position of the butt joint 54 at the end of the middle beam 52 above the bottom mold assembly 3 corresponds to the position of the row of reserved holes at the frontmost end of the pre-formed segment beam on the matching station 62. Since several precision-rolled threaded steel bars are symmetrically connected to both sides of the bottom of each segment beam during production, when the precision-rolled threaded steel bars are removed later, a through hole is left on the bottom surface of the segment beam. When producing the next segment beam, this reserved hole can be used to insert the top beam 53, which extends to the end of the middle beam 52 outside the pressure plate 51, through the precision-rolled threaded steel bars into the reserved hole, thus achieving a direct fixed connection between the inner mold assembly 5 and the adjacent pre-formed segment beam. This further strengthens the connection strength at the end of the inner mold assembly 5.

[0074] Preferably, the inner mold assembly 5 has a pouring port on the pressure plate 51 located at the bottom middle rib position, and a lower cover 55 is detachably connected to its outer side. When pouring the segmental beam, the bottom of the segmental beam is poured first from this pouring port. When it is about to reach the height of the pouring port, the lower cover 55 is used to close the pouring port, and then the pouring is carried out from the highest point of the side mold assemblies 1 on both sides, and the two sides are poured alternately during the pouring.

[0075] As a key inventive feature of this invention, UHPC differs from ordinary concrete. As the pouring progresses, the UHPC poured above the bottom formwork assembly 3 will generate a significant upward buoyancy force on the middle section of the inner formwork assembly 5. In particular, for such ultra-large UHPC segment beams, the middle section will generate an upward buoyancy force of about 600 tons. This is the main reason why the inner formwork assembly 5 is equipped with three layers of pressure from bottom to top: the pressure plate 51, the middle beam 52, and the top beam 53, to prevent deformation of the inner formwork assembly 5.

[0076] UHPC segmental beams are manufactured using a casting process, making it impossible to achieve a perfectly level inner surface. Therefore, in actual production, even a 1mm gap at the joint between the pressure plate 51 and the inner surface of the adjacent pre-formed segmental beam will result in severe grout spraying, making it impossible to seal the gap by pressing down the inner mold assembly 5. Therefore, this invention innovatively designs a flexible connection between the pressure plate 51 and the inner surface of the adjacent pre-formed segmental beam. That is, the pressure plate 51 is suspended above the inner surface of the adjacent pre-formed segmental beam.

[0077] See details Figure 17 As shown, the inner mold assembly 5 also includes an elastic pad 56, which is pasted laterally on the bottom plane of the adjacent pre-formed beam segment before the pressure plate 51 is installed. Then the pressure plate 51 is pressed onto the elastic pad to achieve a soft connection at the joint and eliminate the gap at the joint.

[0078] Preferably, two elastic pads 56 are used, specifically rubber rings, with a natural height between 0.8cm and 1cm. The distance between the end of the pressure plate 51 and the elastic pad 56 is about 1cm. After tightening the nut on the precision-rolled threaded steel, the elastic pad 56 is pressed to a height of 0.2-0.3cm.

[0079] The remaining technical features of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0080] Example 4 This invention also provides a construction method for a combined formwork system for UHPC segmental beams, using the aforementioned combined formwork system, with the following specific steps: Step 1: Template system assembly; The bottom mold assembly 3 corresponding to the segment beam to be produced is transported between the two side mold assemblies 1, and the formed segment beam adjacent to the segment beam to be produced and its corresponding bottom mold assembly 3 are transported to its rear end and aligned.

[0081] The two bottom mold components 3 have the same inclination, and part of the front end of the formed segment beam presses on the bottom mold component 3 corresponding to the segment beam to be produced.

[0082] The drive side support frame 11 moves toward the bottom mold assembly 3 under the action of the sliding unit 13, and aligns the side template 12 with the outer wall of the forming segment beam. When installing the side mold assembly 1, first install the bottom side support frame 11 and the side template 12 onto the sliding unit 13, and then gradually increase the height according to the height of the segment beam to be produced to the specified height.

[0083] Connect the end mold assembly 4 with the side mold assembly 1 and the bottom mold assembly 3, and fix them with bolts.

[0084] Fix both ends of the top frame 2 to the top of the side support frame 11. Specifically, place the two lower crossbeams 21 at the lower end of the top frame 2 into the slots between the side mold assemblies 1 and the third tensioning member 18, insert the connecting rod 183 between the thrust block 23 and the reinforcing plate 182, and then tighten the nuts at both ends.

[0085] The steel reinforcement frame is hoisted using the hanging plate 24 at the lower end of the top frame 2, and the inner formwork assembly 5 is installed.

[0086] Step two: Cast the segmental beams; During pouring, UHPC is first poured into the pouring port on the pressure plate 51 located at the bottom middle rib of the inner mold assembly 5. When it is about to reach the height of the pouring port, the pouring port is closed with the lower cover 55. Then, pouring is carried out from the highest point of the side mold assemblies 1 on both sides. During pouring, the two sides are poured 1m at a time. In order to facilitate the observation of the pouring progress, observation windows can also be opened on the pressure plates 51 on both sides of the inner mold assembly 5.

[0087] Step 3, exit the template; Release the first tensioner 16, the second tensioner 17 and the third tensioner 18 on the side formwork assembly 1, drive the second hydraulic cylinder 25 at the top of the side support frame 11 to push it toward the top frame 2, and use the reaction force to push the upper part of the side support frame 11 to separate from the cast segment beam; If only one side mold assembly 1 separates, the second hydraulic cylinder 25 on the separated side retracts, and the second hydraulic cylinder 25 on the unseparated side pushes the top frame 2 alone, so that the lower thrust block 23 of the top frame 2 abuts against the third tensioning member 18 of the separated side mold assembly 1, and continues to drive the second hydraulic cylinder 25 to move until the unseparated side mold assembly 1 separates from the cast segment beam. Loosen the nut on the support member 15 to drive the first hydraulic cylinder 134 of the sliding unit 13, so that the lower part of the side support frame 11 is also separated from the cast segment beam. Disconnect the inner mold assembly 5 and the end mold assembly 4 from the cast segmental beam; The bottom formwork component 3, along with the poured segmental beam, is moved out along the track by a transfer vehicle.

Claims

1. A combined formwork system for UHPC segmental beams, characterized in that, It includes two side mold components (1) arranged opposite to each other, a bottom mold component (3) is provided at the lower part between the two side mold components (1), an end mold component (4) is provided in front of the bottom mold component (3), and the tops of the two side mold components (1) are connected to the top frame (2). The side mold assembly (1) includes a side support frame (11). The bottom of the side support frame (11) is connected to a sliding unit (13) and can slide left and right. The side support frame (11) facing the bottom mold assembly (3) is connected to the side template (12) through a second tensioner (17). The bottom of the side support frame (11) is connected to the bottom mold assembly (3) through a first tensioner (16), and the top is connected to several third tensioners (18). An opening groove structure is formed between the third tensioners (18) and the side support frame (11). The top frame (2) includes several lower crossbeams (21) arranged horizontally at the bottom. Thrust blocks (23) are provided at both ends of the lower crossbeams (21). The two ends of the lower crossbeams (21) are respectively located in the opening groove between the third tension member (18) and the side support frame (11). The thrust blocks (23) are located inside the third tension member (18) and there is a gap between them. A screw is passed between the thrust blocks (23) and the third tension member (18). The two ends of the screw are fixed with nuts. It also includes an inner mold assembly (5), located inside the U-shaped frame formed by the side mold assembly (1) and the bottom mold assembly (3).

2. The combined template system according to claim 1, characterized in that, The top frame (2) is connected to the adjacent lower crossbeams (21) by a longitudinal beam (22), and the top of the side support frame (11) is connected to a mounting base (115). A telescopic cylinder is installed on the mounting base (115), and the rod head of the telescopic cylinder can abut against the adjacent longitudinal beam (22).

3. The combined template system according to claim 1, characterized in that, The side mold assembly (1) also includes a fixed platform (14), the sliding unit (13) is located on the upper surface of the fixed platform (14), and a number of support members (15) are fixed at the end of the fixed platform (14) away from the bottom mold assembly (3). The bottom end of the side support frame (11) away from the bottom mold assembly (3) is connected to the support member (15).

4. The combined template system according to claim 1, characterized in that, The side support frame (11) is a triangular frame structure, including several horizontal braces (111), vertical braces (112), diagonal braces (113) and internal reinforcing braces. A longitudinal brace (114) is also connected between adjacent horizontal braces (111), vertical braces (112) and diagonal braces (113).

5. The combined template system according to claim 1, characterized in that, The side support frame (11) is higher than the side template (12), and a workbench (19) is provided on the outer side of the top.

6. The combined template system according to claim 1, characterized in that, The third tensioning member (18) includes an L-shaped side brace (181) connected to the top side of the side support frame (11) and parallel to the side template (12). The lower left and right sides of the side brace (181) are provided with reinforcing plates (182) connected to the side support frame (11). The reinforcing plates (182) and the thrust block (23) have through holes for the connecting rod (183) to pass through.

7. The combined template system according to claim 4, characterized in that, The side template (12) is provided with a number of longitudinal supports (114) on the side facing the side support frame (11), and the longitudinal supports (114) include U-shaped connectors; The second tensioning member (17) includes an outer clamp (171), which is clamped on the side of the vertical support (112) of the side support frame (11) away from the side template (12). A screw is provided on the outer clamp (171), and one end of the screw is connected to a hook (172). The hook (172) includes an upper lower hook and a lower straight support plate. The hook (172) can clamp the longitudinal support (114). The other end of the screw is provided with a locking nut.

8. The combined template system according to claim 1, characterized in that, The first tensioning member (16) includes a diagonal tie rod. The bottom mold assembly (3) has a tensioning seat (313) on one side. One end of the diagonal tie rod is connected to the tensioning seat (313), and the other end is inclined upward and connected to the side support frame (11).

9. The combined template system according to claim 1, characterized in that, The sliding unit (13) includes a sliding seat (131) on which a sliding frame (132) is slidably connected. Both ends of the sliding frame (132) are hinged with elastic connectors (133), and the elastic connectors (133) are elastically connected to the lower end of the side support frame (11). It also includes a telescopic cylinder for driving the sliding frame (132) to move.

10. A construction method for a combined formwork system for UHPC segmental beams, characterized in that, The specific steps of using the combined template system according to any one of claims 2-9 are as follows: Step 1: Template system assembly; Transport the bottom mold assembly (3) corresponding to the segment beam to be produced to the two side mold assemblies (1), and transport the formed segment beam adjacent to the segment beam to be produced and its corresponding bottom mold assembly (3) to its rear end and align them. The drive side support frame (11) moves towards the bottom mold assembly (3) under the action of the sliding unit (13), and makes the side template (12) flush with the outer wall of the forming segment beam; Connect the end mold assembly (4) to the side mold assembly (1) and the bottom mold assembly (3); Fix both ends of the top frame (2) to the top of the side support frame (11); Hoist the steel reinforcement cage and install the inner formwork assembly (5); Step two: Cast the segmental beams; Step 3, exit the template; Release the first tensioner (16), the second tensioner (17) and the third tensioner (18) on the side formwork assembly (1), drive the telescopic cylinder at the top of the side support frame (11) to push towards the top frame (2), and use the reaction force to push the upper part of the side support frame (11) to separate from the cast segment beam; If only one side formwork assembly (1) separates, control the retraction of the telescopic cylinder on the separated side, and push the top frame (2) separately with the telescopic cylinder on the unseparated side, so that the lower thrust block (23) of the top frame (2) abuts against the third tensioning member (18) of the side formwork assembly (1) on the separated side, and continue to drive the telescopic cylinder to move until the side formwork assembly (1) on the unseparated side separates from the cast segment beam; Drive the sliding unit (13) to separate the lower part of the side support frame (11) from the cast segment beam; Disconnect the inner formwork assembly (5) and the end formwork assembly (4) from the cast segment beam; The bottom formwork assembly (3) along with the cast segment beam is moved out along the track by a transfer vehicle.

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