UHPC (Ultra High Performance Concrete) non-dismantling formwork pier, UHPC formwork forming device and pier construction method

Abstract

The invention relates to the technical field of bridge engineering piers, and discloses a UHPC non-dismantling formwork pier, a UHPC formwork forming device and a pier construction method.The UHPC non-dismantling formwork pier comprises a non-dismantling formwork, a vertical stress component and a stress base body, the non-dismantling formwork comprises a formwork body and a reinforcing framework, the reinforcing framework is pre-fixed to the formwork body and comprises stirrups and positioning blocks, and the positioning blocks are fixed to the stirrups and the positioning blocks; the stirrup is spirally wound in the formwork body, at least one part of the stirrup is embedded into the inner wall of the formwork body, the inner wall of the formwork body or the inner wall of the formwork body and the stirrup form a constraint area, the positioning block is provided with a first positioning hole matched with a vertical stress component, and the projection of the first positioning hole in the vertical direction is located in the constraint area. The vertical stress component penetrates through the first positioning hole, and the constraint area is filled with the stress base body. The bearing capacity, economical efficiency, durability and construction efficiency of the pier can be improved.

Description

Technical Field

[0001] This invention relates to the field of bridge pier technology, and in particular to a UHPC formwork-free pier, a UHPC formwork forming device, and a pier construction method. Background Technology

[0002] Formwork plays a crucial role in bridge pier construction, and its type and quality often significantly impact the appearance and overall quality of the pier. Currently, large steel formwork is commonly used in bridge pier construction, but it has the following drawbacks: 1. Poor durability and susceptibility to corrosion: Steel formwork exposed to the natural environment for extended periods is highly susceptible to electrochemical corrosion and rust. This not only affects the lifespan of the formwork itself, but the rust can also contaminate the surface of newly poured concrete, impacting the appearance and quality of the bridge piers.

[0003] 2. Low construction efficiency: In order to ensure the demolding effect and prevent rust, the steel formwork must be thoroughly cleaned, polished and coated with release agent before and after each use, which greatly increases the construction cycle.

[0004] 3. High usage cost: Although steel formwork can be reused, as a temporary formwork, it needs to be dismantled, transported and stored after the end of a single project, which will generate corresponding logistics and management costs; for bridge piers and columns in coastal areas, steel formwork is susceptible to corrosion by harmful ions, which accelerates rusting and results in a low turnover rate.

[0005] 4. Safety risks during dismantling: The steel formwork needs to be dismantled after the concrete is poured. The dismantling of the formwork for the tall bridge piers is a high-altitude operation with limited operating space and a complex process. There are safety risks such as falling objects and falls from heights when dismantling and hoisting the heavy steel formwork.

[0006] Therefore, it is necessary to provide a UHPC formwork-free bridge pier and bridge pier construction method that is more economical, durable and efficient in bridge pier construction. Summary of the Invention The technical problem to be solved by the present invention is to provide a UHPC formwork-free bridge pier, which improves the bearing capacity, economy, durability and construction efficiency of the bridge pier.

[0007] The technical problem to be solved by the present invention is to provide a UHPC template forming device to improve the load-bearing capacity, economy, durability and construction efficiency of bridge piers.

[0008] The technical problem to be solved by this invention is to provide a construction method for UHPC formwork-free bridge piers, which improves the bearing capacity, economy, durability and construction efficiency of bridge piers.

[0009] To address the aforementioned technical problems, this invention provides a UHPC (Ultra-High-Performance Concrete) formwork pier, comprising a formwork that can be dismantled, a vertical load-bearing component, and a compression-bearing matrix. The formwork includes a formwork body and a reinforcing frame. The reinforcing frame is pre-fixed to the formwork body and includes stirrups and positioning blocks. The stirrups are spirally wound around the formwork body, and at least a portion of the stirrups is embedded in the inner wall of the formwork body. The inner wall of the formwork body, or the stirrups, or the inner wall of the formwork body forms a constraint zone with the stirrups. The positioning block has a first positioning hole adapted to the vertical load-bearing component. The projection of the first positioning hole in the vertical direction is located within the constraint zone. The vertical load-bearing component passes through the first positioning hole, and the compression-bearing matrix fills the constraint zone.

[0010] As an improvement to the above solution, the non-removable template includes at least one template segment, each template segment is provided with a connecting tongue and groove, and two adjacent template segments are connected through the connecting tongue and groove.

[0011] As an improvement to the above solution, the stirrups are continuously wound around and fixed to the entire inner wall of the template segment.

[0012] As an improvement to the above solution, a temporary reinforcement component is also included, which includes a clamp assembly, a temporary ground anchor, and a guy rope. Two adjacent template segments are connected by a clamp assembly, which includes an upper clamp and a lower clamp. The upper clamp and the lower clamp are respectively clamped to the outer wall of the joint end of the two adjacent template segments. The upper clamp and the lower clamp are each connected end to end by at least two clamp units. Each clamp unit is provided with a longitudinal rib, a transverse rib and a first connecting hole. The transverse rib extends circumferentially, and the longitudinal rib vertically connects two adjacent transverse ribs. The first connecting hole connects two clamp units through a connector. The upper clamp and the lower clamp are provided with corresponding positioning posts and second positioning holes. The positioning posts extend into the second positioning holes to achieve circumferential positioning of the upper clamp and the lower clamp. The temporary ground anchor is arranged around the non-removable template. The temporary ground anchor is equipped with a lifting ring. The lower clamp is equipped with a second connecting hole. The two ends of the guy rope are respectively connected to the second connecting hole and the lifting ring.

[0013] As an improvement to the above solution, it also includes a cap beam and a foundation. The temporary reinforcement component also includes a connecting beam. The non-removable template is arranged in at least two along the first direction. The cap beam, the foundation, and the connecting beam all extend along the first direction. The cap beam is located at the top of the non-removable template, the foundation is located at the bottom of the non-removable template, and the connecting beam is connected to two adjacent upper clamps and two adjacent lower clamps in the first direction.

[0014] In addition, the present invention also provides a UHPC template forming device for forming the above-mentioned non-removable template, which includes an inner mold assembly, an outer mold assembly, a support mechanism and a rotation drive mechanism; The outer mold assembly has an outer mold cavity and a feed port communicating with the outer mold cavity. The inner mold assembly has an inner mold cavity, and the inner mold cavity has a magnetic suction platform and pre-embedded positioning holes corresponding to the stirrups and the positioning blocks. The inner mold assembly is located in the outer mold cavity, and the outer wall of the inner mold assembly and the wall of the outer mold cavity form a cavity. The support mechanism is located inside the inner mold cavity. The support mechanism is provided with a telescopic rod extending radially, and the telescopic rod is provided with an electromagnet corresponding to the magnetic suction platform. The rotary drive mechanism is connected to the support mechanism. When the electromagnet is energized, the magnetic platform and the electromagnet attract each other, and the support mechanism is driven by the rotary drive mechanism to rotate the inner mold assembly relative to the outer mold assembly.

[0015] Furthermore, this invention also provides a construction method for UHPC formwork-free bridge piers, which includes... Step S1: Provide a pre-fixed, non-removable template with a reinforced frame, and reserve vertical load-bearing components on the bridge pier cap at the construction site; Step S2: Horizontally position the template without disassembly, and hoist the template segments that connect the template without disassembly from bottom to top, so that the vertical load-bearing components pass through the first positioning holes of the corresponding positioning blocks on the template without disassembly. Step S3: Fill the constraint area of ​​the non-removable template with the pressure-bearing matrix so that the pressure-bearing matrix fills the entire constraint area.

[0016] As an improvement to the above scheme, step S3 includes Step S3-1: Cast temporary ground anchors at predetermined positions around the piers, connect two vertically adjacent template segments with clamp assemblies, connect the clamp assemblies to the temporary ground anchors with guy ropes, and connect two horizontally adjacent templates that do not need to be removed with connecting beams. Step S3-2: Fill the constraint area of ​​the non-removable template with the pressure-bearing matrix so that the pressure-bearing matrix fills the entire constraint area. Step S3-3: After the compressed substrate reaches the predetermined strength, remove the guy ropes, temporary ground anchors, connecting beams and clamp components, and continue construction of the cap beam on top of the formwork that does not need to be removed.

[0017] As an improvement to the above solution, step S1 involves providing a pre-fixed, non-removable template with a reinforcing skeleton, including... Step S1-1: Assemble the inner mold assembly, place the inner mold assembly on the support mechanism, and energize the support mechanism so that the electromagnet is attracted to the magnetic platform; assemble the support mechanism, the rotary drive mechanism, and the outer mold assembly, and pre-embed the stirrups and positioning blocks during the assembly process; Step S1-2: Turn on the rotary drive mechanism to rotate the support mechanism and inner mold assembly, pour UHPC into the feed port, and after the UHPC overflows, scrape the UHPC at the feed port. Steps S1-3: After the UHPC has initially solidified, remove the UHPC template forming device and perform high-temperature steam curing on the template that does not need to be removed. Steps S1-4: Store the cured, non-removable templates in the designated location, ready for transportation.

[0018] As an improvement to the above solution, in step S2, the template segments of the non-removable template are hoisted sequentially from bottom to top, so that the vertical load-bearing components pass through the first positioning holes of the corresponding positioning blocks on the non-removable template. S2-1, Apply adhesive layer to the location where the formwork can be removed from the pier cap, hoist the first layer of formwork segments into place, place and connect the vertical load-bearing components, install clamps on the upper end of the first layer of formwork segments, and check the verticality and joint sealing of the first layer of formwork segments. S2-2, apply adhesive layer to the tongue and groove joint of the first layer template segment, install the lower clamp on the second layer template segment, hoist the second layer template segment above the first layer template segment, fix the position of the second layer template segment through the tongue and groove joint and the second positioning hole on the clamp, and check the verticality and joint sealing of the second layer template segment; S2-3, connecting the vertical force-bearing member of the first layer template segment with the vertical force-bearing member of the second layer template segment, ensuring that the vertical force-bearing member of the second layer template segment passes through the corresponding first positioning hole; S2-4, apply adhesive layer to the tongue and groove joint of the second layer template segment, install the lower clamp on the third layer template segment, hoist the third layer template segment above the second layer template segment, fix the position of the third layer template segment through the tongue and groove joint and the second positioning hole on the clamp, and check the verticality and joint sealing of the third layer template segment. S2-5 connects the vertical load-bearing member of the second-layer template segment with the vertical load-bearing member of the third-layer template segment, ensuring that the vertical load-bearing member of the third-layer template segment passes through the corresponding first positioning hole.

[0019] Implementing this invention has the following beneficial effects: This invention discloses a UHPC (Ultra-High-Performance Polymer) formwork pier. The formwork body is made of UHPC material, which has excellent properties such as high strength, toughness, and high durability. Combined with a reinforcing frame, it forms a permanent, non-removable formwork. This not only improves construction efficiency but also significantly enhances the performance and service life of the pier structure. Before the compression matrix is ​​poured and filled, the reinforcing frame is pre-fixed to the formwork body. The stirrups of the reinforcing frame are spirally wound around the formwork body, and at least a portion of the stirrups are embedded in the inner wall of the formwork body. The stirrups and the formwork body together constitute a permanent composite load-bearing system for the pier. This not only enhances the crack resistance of the UHPC formwork and prevents cracking during transportation and hoisting but also… To enhance the constraint effect of the UHPC (Ultra-High-Pressure Polymer) formwork on the subsequently poured pressure-bearing matrix, thereby increasing the overall load-bearing capacity of the bridge pier; in addition, the positioning blocks of the reinforcing frame are also pre-fixed on the formwork body, and the projection of the first positioning hole of the positioning block in the vertical direction is located within the constraint area formed by the inner wall of the formwork body, or within the constraint area formed by the stirrups, or within the constraint area formed by the inner wall of the formwork body and the stirrups. The vertical load-bearing member passes through the first positioning hole. The vertical load-bearing member is constrained by the positioning block on the UHPC formwork and will not shift during the pouring and filling of the pressure-bearing matrix, so that the vertical load-bearing member can maintain a vertical state for support, which can further enhance the overall load-bearing capacity of the bridge pier; The present invention also discloses a UHPC formwork forming device and a construction method for UHPC non-removable formwork bridge piers, which realizes the prefabrication of formwork in the factory, on-site splicing, and permanent use without dismantling, while having a low cost and significantly improving the economy, durability and construction efficiency of bridge piers. Attached Figure Description

[0020] Figure 1 This is a structural schematic diagram of an embodiment of a UHPC formwork-free bridge pier according to the present invention; Figure 2 yes Figure 1 A schematic diagram of the bridge pier after it has been solidified and the temporary reinforcement components have been removed; Figure 3 It is a schematic diagram of the assembly structure of the formwork or formwork segment and the vertical load-bearing component without disassembly; Figure 4 This is a schematic diagram of the connection structure between two adjacent template segments; Figure 5 This is a structural schematic diagram of the clamp assembly; Figure 6 This is a schematic diagram of an embodiment of a UHPC template forming device according to the present invention; Figure 7 yes Figure 6 Schematic diagram of the structure of the Chinese and foreign mold components; Figure 8 yes Figure 6 Schematic diagram of the inner mold assembly; Figure 9 yes Figure 6 Schematic diagram of the installation structure of the intermediate support mechanism and bracket; Figure 10 This is a structural schematic diagram of the support mechanism; Figure 11 This is a flowchart of a construction method for a UHPC (Ultra-High-Pressure Construction) formwork-free bridge pier according to the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0022] like Figures 1 to 5 As shown, the present invention discloses a first embodiment of a UHPC (Ultra-High Performance Concrete) formwork-free bridge pier, including a formwork-free 1, a vertical load-bearing member 2, and a compression substrate (not shown in the figure). The formwork-free 1 includes a formwork body 11 and a reinforcing frame. The formwork body 11 is made of UHPC. The reinforcing frame is pre-fixed to the formwork body 11. The reinforcing frame includes stirrups 12 and positioning blocks 13. The stirrups 12 are spirally wound inside the formwork body 11, and at least a portion of the stirrups 12 is embedded in the inner wall of the formwork body 11. The inner wall of the formwork body 11, or the stirrups 12, or the inner wall of the formwork body 11 forms a constraint area with the stirrups 12. The positioning block 13 is provided with a first positioning hole 131 adapted to the vertical load-bearing member 2. The projection of the first positioning hole 131 in the vertical direction is located within the constraint area. The vertical load-bearing member 2 passes through the first positioning hole 131, and the compression substrate fills the constraint area.

[0023] In this embodiment, the template body 11 is made of UHPC material with excellent properties such as high strength, toughness, and high durability. Combined with a reinforcing skeleton, it forms a permanent, non-removable template 1. This not only improves construction efficiency but also significantly enhances the performance and service life of the bridge pier structure. Before the compression matrix is ​​poured and filled, the reinforcing skeleton is pre-fixed to the template body 11. The stirrups 12 of the reinforcing skeleton are spirally wound inside the template body 11, and at least a portion of the stirrups 12 are embedded in the inner wall of the template body 11. The stirrups 12 and the template body 11 together constitute a permanent composite load-bearing system for the bridge pier. This not only enhances the crack resistance of the UHPC non-removable template 1, preventing cracking during transportation and hoisting, but also strengthens the UHPC non-removable template 1. The constraint effect on the subsequently poured pressure-bearing matrix enhances the overall bearing capacity of the pier. In addition, the positioning block 13 of the reinforcing frame is also pre-fixed on the template body 11, and the projection of the first positioning hole 131 of the positioning block 13 in the vertical direction is located in the constraint area formed by the inner wall of the template body 11, or in the constraint area formed by the stirrup 12, or in the constraint area formed by the inner wall of the template body 11 and the stirrup 12. The vertical force-bearing member 2 passes through the first positioning hole 131. The vertical force-bearing member 2 is constrained by the positioning block 13 on the template 1 and will not shift during the pouring and filling of the pressure-bearing matrix, so that the vertical force-bearing member 2 can maintain a vertical state for support, which can further enhance the overall bearing capacity of the pier.

[0024] In this embodiment, the template body 11 is cast using UHPC. UHPC has extremely high strength, toughness, and durability. Compared to ordinary concrete structures, UHPC structures are thinner and lighter, and compared to steel structures, they have better durability and economy. In this embodiment, the pressure-bearing base is cast from concrete, the vertical load-bearing member 2 is made of steel reinforcement, and the stirrups 12 and positioning blocks 13 are preferably steel structural components.

[0025] The stirrups 12 are spirally wound inside the template body 11, and at least a portion of the stirrups 12 are embedded in the inner wall of the template body 11. The inner wall of the template body 11, or the inner wall of the template body 11 and the stirrups 12 form a constraint area, which can be divided into the following two situations: that is, the stirrups 12 are partially exposed outside the inner wall of the template body 11, and the stirrups 12 are completely embedded in the template body 11 and covered by the inner wall of the template body 11. When the stirrups 12 are partially exposed on the inner wall of the formwork body 11, there may be situations where the stirrups 12 partially cover the formwork body 11, and the inner wall of the formwork body 11 and the surface of the stirrups 12 exposed on the formwork body 11 form a constraint zone; or the stirrups 12 cover the entire formwork body, and the inner wall of the UHPC formwork 1 is entirely the surface of the stirrups 12. When the stirrups 12 are completely embedded in the formwork body 11, the inner wall of the formwork body 11 forms a constraint zone. In both cases, the stirrups 12 and the formwork body 11 can form a permanent composite force system for the pier, enhance the crack resistance of the UHPC formwork 1, enhance the constraint effect of the UHPC formwork 1 on the subsequently poured compression matrix, and enhance the overall bearing capacity of the pier.

[0026] To facilitate the molding of the non-removable template 1, this embodiment sets the non-removable template 1 as a structure with at least one template segment connection. Each template segment is provided with a connecting tongue and groove 111, and two adjacent template segments are joined together through the connecting tongue and groove 111. Each template segment includes a template body 11 and a reinforcing skeleton pre-fixed to the template body 11. The reinforcing skeleton includes stirrups 12 and positioning blocks 13. Before pouring the pressure-bearing substrate, i.e., concrete, the stirrups 12 and positioning blocks 13 are pre-fixed in the template body 11. The connecting tongue and groove 111 is specifically formed on the template body 11 of the template segment. The cross-section of the connecting tongue and groove 111 along the axial direction of the template segment is L-shaped, and two upper and lower template segments are joined together through the connecting tongue and groove 111. The L-shaped connecting tongue and groove 111 is simple to prefabricate and can ensure stable connection of UHPC template segments. The contact surface of the connecting tongue and groove 111 of two template segments is coated with 1~3mm thick epoxy resin adhesive 10 to achieve sealing.

[0027] The spirally arranged stirrups 12 are at least partially embedded in the inner wall of the template body 11, forming a composite structural system together with the template body 11. The stirrups 12 and the positioning blocks 13 can be fixed in the template segment by pre-embedding, adhesive bonding or chemical anchors.

[0028] Preferably, in this embodiment, the stirrups 12 are continuously wound around and fixed to the entire inner wall of the template segment, that is, the stirrups 12 are complete and continuous metal strips and cover the entire inner wall of the template 1. At this time, the stirrups 12 cover the entire template body, and the inner wall of the template 1 is entirely the surface of the stirrups 12, so that the force between the stirrups 12 and the template body 11 is continuous and uniform, thereby improving the stability and bearing capacity of the pier.

[0029] The positioning block 13 connects the vertical load-bearing member 2 to the template body 11, enabling the vertical load-bearing member 2 to maintain a vertical state for support. In this embodiment, the positioning block 13 is preferably arranged in a ring array on the template body 11, and the vertical load-bearing member 2 is also arranged in a ring array within the constraint area. The positioning block 13 improves the structural correlation between the template 1, the vertical load-bearing member 2 and the pressure-bearing base to a certain extent, and improves the uniformity of the overall stress on the pier, thereby improving the bearing capacity and durability of the pier.

[0030] The vertical force-bearing member 2 passes through at least one template segment and through the first positioning hole 131 of the positioning block 13 on the template segment. When the vertical force-bearing member passes through only one template segment, it is preferable to provide at least two positioning blocks 13 in the axial direction of each template segment so that a vertical force-bearing member can pass through two first positioning holes 131 at the same time to achieve vertical positioning; when the length of the vertical force-bearing member is much longer than one template segment, the vertical force-bearing member can pass through the first positioning holes 131 of the positioning blocks 13 on multiple template segments sequentially from bottom to top.

[0031] To improve the structural stability of the formwork 1 during the filling of the compressed substrate and the hardening process of the compressed substrate in the constrained area, and to enhance the wind resistance of the pier, the UHPC formwork pier of this embodiment also includes a temporary reinforcement component, which includes a clamp assembly 3, a temporary ground anchor 4, and a guy rope 5.

[0032] In this configuration, two adjacent template segments are connected by a clamp assembly 3, which includes an upper clamp 31 and a lower clamp 32. The upper clamp 31 and the lower clamp 32 respectively clamp onto the outer wall of the mating end of two adjacent template segments. Each upper clamp 31 and lower clamp 32 consists of at least two clamp units connected end-to-end. Each clamp unit is provided with a longitudinal rib 3a, a transverse rib 3b, and a first connecting hole 3c. The transverse rib 3b extends circumferentially, and the longitudinal rib 3a vertically connects two adjacent transverse ribs 3b. The first connecting hole 3c connects two clamp units via a connector. The upper clamp 31 and the lower clamp 32 are provided with corresponding positioning posts 3d and second positioning holes 3e. The positioning posts 3d extend into the second positioning holes 3e to achieve circumferential positioning of the upper clamp 31 and the lower clamp 32, ensuring the planar positioning accuracy of the UHPC template segments and preventing template segment misalignment.

[0033] The temporary anchor 4 is preferably installed around the formwork 1 that can be removed, specifically by casting C30 concrete below the ground. A lifting ring 4a is pre-embedded in the temporary anchor 4. A second connecting hole 321 is provided on the lower clamp 32, and both ends of the guy rope 5 are connected to the second connecting hole 321 and the lifting ring 4a respectively. The guy rope 5 is made of steel wire rope, and the angle between the guy rope 5 and the vertical direction is between 30° and 45°. The diameter of the guy rope 5 is calculated and determined based on the height and angle of the formwork 1 that can be removed, ensuring the stability of the pier under a certain wind pressure range.

[0034] This embodiment of the UHPC formwork pier also includes a cap beam 6 and a foundation 7. The temporary reinforcement assembly also includes a connecting beam 8. The formwork 1 is arranged in at least two configurations along a first direction. The cap beam 6, the foundation 7, and the connecting beam 8 all extend along the first direction. The cap beam 6 is located at the top of the formwork 1, and the foundation 7 is located at the bottom of the formwork 1. Preferably, positioning blocks 13 are provided at both ends of the formwork segment. The foundation 7 is provided with a foundation load-bearing component corresponding to the positioning block 13. The foundation load-bearing component and the vertical load-bearing component 2 are both reinforcing bars, which extend vertically and into the first positioning hole 131 of the positioning block 13. The connecting beam 8 is preferably connected to two adjacent upper clamps 31 and two adjacent lower clamps 32. The cap beam 6 and the foundation 7 connect two adjacent templates 1 that are not removed along the first direction to form a whole support structure, thereby improving the load-bearing capacity; while the connecting beam 8 can further improve the wind resistance and stability of the templates 1 during the filling of the compressed substrate and during the hardening of the compressed substrate in the constrained area.

[0035] In addition, combined Figures 6 to 10The present invention also provides an embodiment of a UHPC template forming device for forming the aforementioned non-removable template 1. The UHPC template forming device includes an inner mold assembly 91, an outer mold assembly 92, a support mechanism 93, and a rotation drive mechanism 94. The outer mold assembly 92 has an outer mold cavity and a feed inlet 921 communicating with the outer mold cavity. Specifically, the outer mold assembly 92 includes a first outer mold 922, a second outer mold 923, and a base 924. The first outer mold 922 and the second outer mold 923 are fixed by bolts. Both the first outer mold 922 and the second outer mold 923 have baffles on the side of the feed inlet 921 to prevent UHPC from overflowing. The upper part of the base 924 has the same curvature as the first outer mold 922 and the second outer mold 923, so that the entire outer mold assembly 92 forms an approximately cylindrical outer mold cavity. The inner mold assembly 91 has an inner mold cavity, within which a magnetic suction platform 911 and pre-embedded part positioning holes 912 corresponding to the stirrups 12 and the positioning blocks 13 are provided. Specifically, the inner mold assembly 91 includes a first inner mold 913, a second inner mold 914, and a third inner mold 915. The first and second inner molds 913 are connected by bearings 916, and the third inner mold 915 is connected to the first and second inner molds 913 and 914 by bolt plates 917. The first and second inner molds 913 and 914 are provided with the magnetic suction platform 911 and pre-embedded part positioning holes 912. The inner mold assembly 91 is located within the outer mold cavity, and its outer wall forms a cavity adapted to the template segment with the wall surface of the outer mold cavity. The support mechanism 93 is located within the inner mold cavity and includes a central support 100 and a telescopic rod 931. The central support 100 specifically includes a central bearing 932, fixed cross braces 933, and fixed diagonal braces 934. The fixed cross braces 933 are arranged circumferentially around the central bearing 932 and extend radially along the central bearing 932. The two ends of the fixed diagonal braces 934 connect to two adjacent fixed cross braces 933. A telescopic rod 931 extends radially and can extend and retract radially within the fixed cross braces 933 along the central bearing 932. An electromagnet 935 corresponding to the magnetic platform 911 is provided at the end of the telescopic rod 931 away from the central bearing 932. The rotary drive mechanism 94 is connected to the support mechanism 93. Specifically, the central bearing 932 of the support mechanism 93 is fitted onto the power output shaft of the rotary drive mechanism 94, so that the support mechanism 93 can be rotated by the rotary drive mechanism 94. The rotary drive mechanism 94 in this embodiment specifically includes a drive motor, a belt, and a drive pulley and a driven pulley 941 connected to the belt. The central bearing 932 is coaxially arranged with the driven pulley 941 and is supported by a bracket 95. The telescopic rod 931 can be configured to extend as the magnetic platform 911 and the electromagnet 935 attract each other, or the telescopic rod 931 can be extended and retracted by a power mechanism.When energized, the magnetic platform 911 and the electromagnet 935 attract each other. The support mechanism 93 is driven by the rotation drive mechanism 94 to rotate the inner mold assembly 91 relative to the outer mold assembly 92. The UHPC in the cavity is evenly distributed as the inner mold assembly 91 rotates, eventually forming a template segment.

[0036] In addition, combined Figure 11 The present invention also provides an embodiment of a construction method for UHPC formwork-free bridge piers, which includes the following steps: Step 1: Provide a pre-fixed, non-removable template 1 with a reinforced frame, store it, and reserve vertical load-bearing components 2 at the bridge pier cap 7 on the construction site; specifically including... Step 1-1: Based on the designed standard segment length of the UHPC template, assemble the UHPC template forming device in the factory. Specifically, connect the first inner mold 913 and the second inner mold 914 with bearings, and fix the third inner mold 915 to the first inner mold 913 and the second inner mold 914 with bolts. Attach the rubber gasket 918 to the bottom of the inner mold assembly 91 with strong adhesive. Place the inner mold assembly 91 onto the support mechanism 93, and energize the support mechanism 93 to extend the telescopic rod 931 and attract the electromagnet 935 to the magnetic platform 911. Assemble the support mechanism 93, the rotary drive mechanism 94, and the outer mold assembly 92, pre-embedding the stirrups 12 and positioning blocks 13 during the assembly process. Step 1-2: Turn on the rotary drive mechanism 94 to make the support mechanism 93 and the inner mold assembly 91 rotate, and pour UHPC evenly and slowly into the feed port 921. After the UHPC overflows, use a scraper with equal arc to smooth the UHPC at the feed port 921. Steps 1-3: After the UHPC has initially solidified, remove the UHPC template forming device and perform high-temperature steam curing on the template 1 that does not need to be removed. Steps 1-4: Store the cured, non-removable template 1 in the designated location, ready for transportation.

[0037] Step 2: Install the non-removable template 1 as a permanent outer formwork on-site. Specifically, horizontally position the non-removable template 1, and then sequentially hoist and connect the first layer template segment a, the second layer template segment b, and the third layer template segment c from bottom to top. Depending on the pier height, the third layer template segment c can have n segments, where n is 0 or a positive integer, and the connection method is the same. Ensure that the vertical load-bearing member 2 passes through the first positioning hole 131 of the corresponding positioning block 13 on the non-removable template 1. Specifically, this includes... Step 2-1: Reserve connecting steel bars above the pier cap 7 at the construction site, pour a ring of concrete for limiting the UHPC formwork, apply an adhesive layer to the placement position of the non-removable formwork 1 on the pier cap 7, hoist the first layer formwork segment a into place, place and connect the vertical load-bearing member 2, and install a clamp 31 on the upper end of the first layer formwork segment a. Check the verticality and joint sealing of the first layer formwork segment a. Epoxy resin adhesive can be used for the adhesive layer.

[0038] Step 2-2: Apply adhesive layer to the tongue and groove joint 111 of the first layer template segment a, install the lower clamp 32 on the second layer template segment b, hoist the second layer template segment b above the first layer template segment a, fix the position of the second layer template segment b through the tongue and groove joint 111 and the second positioning hole 3e on the clamp, and check the verticality and joint sealing of the second layer template segment b. Step 2-3: Connect the vertical force-bearing member 2 of the first layer template segment a to the vertical force-bearing member 2 of the second layer template segment b, ensuring that the vertical force-bearing member 2 of the second layer template segment b passes through the corresponding first positioning hole 131; Step 2-4: Apply adhesive layer to the tongue and groove joint 111 of the second layer template segment b, install the lower clamp 32 on the third layer template segment c, hoist the third layer template segment c above the second layer template segment b, fix the position of the third layer template segment through the tongue and groove joint 111 and the second positioning hole 3e on the clamp, and check the verticality and joint sealing of the third layer template segment c. Steps 2-5: Connect the vertical force-bearing member 2 of the second-layer template segment b to the vertical force-bearing member 2 of the third-layer template segment c, ensuring that the vertical force-bearing member 2 of the third-layer template segment c passes through the corresponding first positioning hole 131.

[0039] Step 3: Fill the constraint area of ​​the non-removable template 1 with the pressure-bearing matrix, ensuring the pressure-bearing matrix completely fills the constraint area; specifically including... Step 3-1: Cast temporary ground anchors 4 at predetermined positions around the bridge piers, connect two vertically adjacent template segments with clamp components 3, connect clamp components 3 to temporary ground anchors 4 with guy ropes 5, and connect two horizontally adjacent templates 1 that do not need to be dismantled with connecting beams 8; wherein, a set of guy ropes 5 and connecting beams 8 is set every 8~10m. Step 3-2: Check the verticality, stability and joint sealing of the template. Then fill the constraint area of ​​the template 1 with the pressure-bearing matrix until the pressure-bearing matrix fills the entire constraint area. Step 3-3: After the pressure-bearing base reaches the predetermined strength, remove the guy ropes 5, temporary ground anchors 4, connecting beams 8 and clamp components 3, and continue construction of the cap beam 6 on top of the formwork 1 that does not need to be removed.

[0040] The UHPC formwork piers without dismantling of the present invention have the following beneficial effects: 1. High precision and no deformation: UHPC material has a high elastic modulus, and UHPC formwork has little deformation under the lateral pressure of concrete. In addition, factory prefabrication ensures the high precision of the formwork itself, which improves the appearance and quality of the bridge pier. 2. Highly efficient assembly and excellent sealing: The large-section, cylindrical design significantly reduces the number of seams; the use of clamps, interlocking joints, and high-performance epoxy resin adhesive ensures the tightness of the joints and effectively prevents grout leakage. 3. Good durability and low cost: UHPC material has excellent wear resistance and corrosion resistance. As a permanent formwork, UHPC formwork piers are not prone to damage during long-term use, which greatly reduces the later maintenance cost and has significant overall economic benefits. 4. No dismantling required, highly efficient construction: UHPC formwork piers can be prefabricated in large quantities in the factory and assembled on site as permanent formwork, requiring no dismantling later. The entire construction process is simple and clear, with quick and accurate formwork positioning, significantly improving construction speed; 5. Strong overall bearing capacity and good stability of the pier: The stirrups 12 and the formwork body 11 together form a permanent composite force system for the pier. This not only enhances the crack resistance of the UHPC formwork 1 and prevents cracking during transportation and hoisting, but also enhances the constraint effect of the UHPC formwork 1 on the subsequently poured pressure base, thereby enhancing the overall bearing capacity of the pier. Furthermore, the vertical force-bearing member 2 is constrained by the positioning block 13 on the formwork 1 and will not shift during the pouring and filling of the pressure base, allowing the vertical force-bearing member 2 to remain vertical for support, which further enhances the overall bearing capacity of the pier.

[0041] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A UHPC formwork-free bridge pier, characterized in that, The removable formwork comprises a formwork body and a reinforcing framework, the reinforcing framework is pre-fixed on the formwork body, the reinforcing framework comprises a stirrup and a positioning block, the stirrup is spirally arranged in the formwork body, and at least a part of the stirrup is embedded in the inner wall of the formwork body, the inner wall of the formwork body, or the stirrup, or the inner wall of the formwork body and the stirrup form a constraint area, the positioning block is provided with a first positioning hole matched with the vertical force bearing member, the projection of the first positioning hole in the vertical direction is located in the constraint area, the vertical force bearing member passes through the first positioning hole, and the compression base is filled in the constraint area.

2. The UHPC formwork bridge pier of claim 1, wherein, The removable formwork comprises at least one formwork segment, each formwork segment is provided with a connecting groove, and adjacent two formwork segments are connected through the connecting grooves.

3. The UHPC formwork bridge pier of claim 2, wherein, The stirrup is continuously arranged and fixed on the whole inner wall of the formwork segment.

4. The UHPC formwork bridge pier of claim 2, wherein, The removable formwork further comprises a temporary reinforcing assembly, the temporary reinforcing assembly comprises a hoop assembly, a temporary anchor and a cable wind rope. The hoop assembly is used for connecting adjacent two formwork segments, the hoop assembly comprises an upper hoop and a lower hoop, the upper hoop and the lower hoop are respectively arranged on the outer walls of the abutting ends of adjacent two formwork segments, the upper hoop and the lower hoop are connected by at least two hoop units, each hoop unit is provided with a longitudinal rib, a transverse rib and a first connecting hole, the transverse rib extends in the circumferential direction, the longitudinal rib is vertically connected with adjacent two transverse ribs, the first connecting hole is connected with two hoop units through a connecting member, the upper hoop and the lower hoop are provided with corresponding positioning columns and second positioning holes, the positioning columns are inserted into the second positioning holes to realize the circumferential positioning of the upper hoop and the lower hoop. The temporary anchor is arranged around the removable formwork, the temporary anchor is provided with a lifting ring, the lower hoop is provided with a second connecting hole, and the two ends of the cable wind rope are respectively connected with the second connecting hole and the lifting ring.

5. The UHPC formwork bridge pier of claim 4, wherein, The removable formwork further comprises a cap beam and a bearing platform, the temporary reinforcing assembly further comprises a connecting beam, the removable formwork is arranged in at least two groups along a first direction, the cap beam, the bearing platform and the connecting beam are arranged along the first direction, the cap beam is arranged on the top of the removable formwork, the bearing platform is arranged on the bottom of the removable formwork, and the connecting beam is connected with adjacent two upper hoops and adjacent two lower hoops in the first direction.

6. A UHPC form forming device for forming the self-curing form according to any one of claims 1 to 5, characterized in that, The removable formwork further comprises an inner mold assembly, an outer mold assembly, a supporting mechanism and a rotating driving mechanism. The outer mold assembly is provided with an outer mold cavity and a feeding port communicated with the outer mold cavity, the inner mold assembly is provided with an inner mold cavity, the inner mold cavity is provided with a magnetic platform and a pre-embedded part positioning hole corresponding to the stirrup and the positioning block, the inner mold assembly is arranged in the outer mold cavity, and the outer wall of the inner mold assembly and the wall surface of the outer mold cavity form a forming cavity. The supporting mechanism is arranged in the inner mold cavity, the supporting mechanism is provided with a telescopic rod extending in the radial direction, and the telescopic rod is provided with an electromagnet corresponding to the magnetic platform. The rotating driving mechanism is connected with the supporting mechanism, when the electromagnet is powered, the magnetic platform and the electromagnet are attracted to each other, the supporting mechanism is driven by the rotating driving mechanism to drive the inner mold assembly to rotate relative to the outer mold assembly.

7. A construction method of the UHPC formwork bridge pier according to any one of claims 1 to 5, characterized in that, Comprise Step S1, provide pre-fixed with reinforced framework of non-dismantling formwork, and pre-reserve vertical load-bearing member in construction site pier cap; Step S2, the non-dismantling formwork is positioned horizontally, and the formwork segments connected with the non-dismantling formwork are hoisted in sequence from bottom to top, so that the vertical load-bearing member passes through the first positioning hole of the corresponding positioning block on the non-dismantling formwork; Step S3, fill the compression matrix into the constraint area of the non-dismantling formwork, so that the compression matrix fills the entire constraint area.

8. The pier construction method according to claim 7, characterized by, Step S3 includes Step S3-1, cast-in-place temporary anchor at the predetermined position around the pier, connect the two vertically adjacent formwork segments with the hoop assembly, connect the hoop assembly with the temporary anchor with the cable wind rope, and connect the two adjacent non-dismantling formworks in the horizontal direction with the connecting beam; Step S3-2, fill the compression matrix into the constraint area of the non-dismantling formwork, so that the compression matrix fills the entire constraint area; Step S3-3, after the compression matrix reaches the predetermined strength, remove the cable wind rope, temporary anchor, connecting beam and hoop assembly, and continue to construct the bent cap on the top of the non-dismantling formwork.

9. The pier construction method according to claim 6, characterized by, Step S1, providing pre-fixed with reinforced framework of non-dismantling formwork includes Step S1-1, assemble the inner mold assembly, put the inner mold assembly on the supporting mechanism, power the supporting mechanism so that the electromagnet is attracted to the magnetic platform; the supporting mechanism, rotating driving mechanism and outer mold assembly are assembled, and the stirrup and positioning block are pre-buried during assembly; Step S1-2, start the rotating driving mechanism to rotate the supporting mechanism and the inner mold assembly, pour UHPC into the feeding port, and after the UHPC overflows, scrape the UHPC at the feeding port; Step S1-3, after the UHPC is initially solidified, remove the UHPC formwork forming device, and perform high-temperature steam curing on the non-dismantling formwork; Step S1-4, store the cured non-dismantling formwork in a designated location for transportation.

10. The pier construction method according to claim 6, characterized by, Step S2, hoist the formwork segments connected with the non-dismantling formwork in sequence from bottom to top, so that the vertical load-bearing member passes through the first positioning hole of the corresponding positioning block on the non-dismantling formwork includes S2-1, apply an adhesive layer at the non-dismantling formwork placement position of the pier cap, hoist the first layer of formwork segments into place, place and connect the vertical load-bearing member, and install the hoop on the upper end of the first layer of formwork segments, and check the perpendicularity and joint tightness of the first layer of formwork segments; S2-2, apply an adhesive layer at the connecting groove position of the first layer of formwork segments, install the lower hoop on the second layer of formwork segments, hoist the second layer of formwork segments above the first layer of formwork segments, fix the position of the second layer of formwork segments through the second positioning hole on the connecting groove and the connecting hoop, and check the perpendicularity and joint tightness of the second layer of formwork segments; S2-3, connect the vertical load-bearing member of the first layer of formwork segments with the vertical load-bearing member of the second layer of formwork segments, and ensure that the vertical load-bearing member of the second layer of formwork segments passes through the corresponding first positioning hole; S2-4, at the connecting groove position of the second layer template section, apply the adhesive layer, install the lower hoop on the third layer template section, hoist the third layer template section above the second layer template section, fix the position of the third layer template section through the connecting groove and the second positioning hole on the connecting hoop, check the perpendicularity and joint sealing of the third layer template section; S2-5, connect the vertical force bearing members of the second layer template section and the vertical force bearing members of the third layer template section, and ensure that the vertical force bearing members of the third layer template section pass through the corresponding first positioning holes.

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