Construction method of prefabricated concrete member temporary support-to-permanent bearing system

Abstract

The invention provides a construction method of a prefabricated concrete member temporary support-to-permanent bearing system, which comprises the following steps of: prefabricating a concrete member in a factory according to the curvature of an arc-shaped arch plate, and reserving a rectangular bearing groove at the top; the prefabricated part is hoisted to the designed position, and lateral clamping constraint is formed through a lower fixing device; steel pipe secondary ridges are installed in the bearing grooves, a matched comb plate formwork is laid on the steel pipe secondary ridges, and the bottom face of the comb plate formwork is attached to the top face of the prefabricated part; pouring concrete around the upper and lower chord plates and the prefabricated parts layer by layer to enable the prefabricated cast-in-place structure to form a whole; the auxiliary support is gradually dismantled along with concrete strength increase, and load transfer to the prefabricated part is completed; and the steel pipe secondary edges and the comb plate formworks are dismantled, the bearing grooves are filled, and a continuous stress section is formed. The problems of eccentric load bearing and structural integrity are solved, the method is suitable for the scene that upper and lower chord plates of the arc-shaped arch slab and prefabricated parts are integrally poured, and the construction efficiency and the structural safety are improved.

Description

Technical Field

[0001] This invention relates to the field of precast component construction and structural load conversion technology, and in particular to a construction method for converting temporary support of precast concrete components into a permanent load-bearing system. Background Technology

[0002] In the construction of arched slab structures, traditional methods commonly employ steel pipe scaffolding to support the formwork system. This process requires erecting a large number of uprights to accommodate varying heights based on the arch's curvature, resulting in a significant increase in the overall material usage of the support system. Furthermore, the varying arch curvature leads to significant differences in upright height, making it difficult to standardize upright specifications across different projects or sections of the same project. This results in low steel pipe utilization and substantial material waste due to the inability to reuse materials.

[0003] During construction, to ensure the stability of the support system, the vertical poles need to be densely arranged. This results in a narrow working space, severely restricting personnel passage and material transfer efficiency, increasing the difficulty of key processes such as concrete pouring, and delaying the overall construction progress. In addition, the concrete partitions lack an effective lateral positioning control mechanism under traditional installation methods, making it difficult to guarantee installation accuracy. This can easily lead to eccentric loading of the partitions, resulting in structural cracks or local deformation in the joint area, threatening the overall structural safety.

[0004] In existing technologies, precast components are typically designed independently of the support system, failing to achieve systematic integration with the support structure. This separate construction method cannot specifically address the unique curvature adaptation, efficient positioning, and stability control requirements of curved arch slabs. The functional disconnect between the support system and precast components makes it difficult for traditional processes to overcome inherent defects such as material waste, low construction efficiency, and structural safety hazards. These problems are particularly pronounced when dealing with large-span or complex curvature arch slabs, necessitating the development of an integrated construction method to optimize resource allocation, improve construction accuracy, and ensure structural reliability. Summary of the Invention

[0005] The main objective of this invention is to provide a construction method for converting temporary support of precast concrete components into a permanent load-bearing system, thereby solving the problems of low construction efficiency and structural safety when the upper and lower chords of the arched slab are cast integrally with the precast components, as well as the problems of eccentric loading and structural integrity. To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a construction method for converting temporary support of precast concrete components into a permanent load-bearing system, the method comprising: S1. Precast concrete components in the factory according to the curvature of the arc-shaped arch plate, with a rectangular bearing groove reserved at the top; S2. Hoist the prefabricated components to the designed position and form lateral clamping constraints through the lower fixing device; S3. Install secondary steel pipe ribs in the bearing groove, and lay a suitable comb plate template on top of the secondary steel pipe ribs so that its bottom surface fits against the top surface of the precast component. S4. Pour the concrete around the upper and lower chords and precast components in layers to make the precast components and cast-in-place structure form an integral whole. S5. As the concrete strength increases, the auxiliary supports are gradually removed to complete the transfer of load to the precast components; S6. Remove the secondary steel pipe ribs and comb plate formwork, fill the bearing groove, and form a continuous stress section; In this process, precast components bear the load of the formwork through the bearing groove during the construction phase, and participate in the permanent bearing of the structure through the filled continuous section during the service phase, thereby realizing the transformation of the dynamic force system.

[0006] In the preferred embodiment, in step S1, the bearing grooves are spaced apart along the length of the arc-shaped arch plate, and the spacing is set to be no greater than the original design pole spacing. The bottom elevation of the bearing trough is set to match the curve of the comb plate template with the curvature of the arc-shaped arch plate after the secondary steel pipe ribs are installed.

[0007] In the preferred embodiment, step S2 includes: S21. Erect a lower chord formwork foundation consisting of steel pipe main beams and square timber secondary beams, and lay the lower chord formwork on the foundation. S22. Tie the bottom chord plate reinforcement on the bottom chord formwork, and pop up the positioning lines of the precast components according to the design position of the structural force transmission path. S23. Hoist the precast component into the positioning line of the lower chord formwork and place it on the first concrete pad within the reinforcement interval of the lower chord plate. S24. L-shaped steel plates are symmetrically arranged on both sides of the precast component, with their vertical sides tightly attached to the bottom side surface of the precast component and their horizontal sides welded and fixed to the lower chord reinforcement.

[0008] In the preferred embodiment, step S2 includes: S21. Erect a lower chord formwork foundation consisting of steel pipe main beams and square timber secondary beams, and lay the lower chord formwork on the foundation. S22. Tie the bottom chord plate reinforcement on the bottom chord formwork, and pop up the positioning lines of the precast components according to the design position of the structural force transmission path. S23. Set a first concrete pad with through holes within the positioning line, and prepare an L-shaped steel plate with U-shaped steel bars connected to the ends, wherein the extension direction of the U-shaped steel bars points to the back side of the vertical plate of the L-shaped steel plate. S24. Hoist the precast component into the lower chord formwork positioning line and place it on the first concrete pad; S25. A symmetrical L-shaped steel plate is set on both sides of the precast component, so that its vertical side is closely attached to the bottom side surface of the precast component. The U-shaped steel bar passes through the through hole in the middle of the first concrete pad from below the bottom chord plate steel bar and extends to a distance to the front end of the horizontal side of the L-shaped steel plate on the opposite side. The extended parts of the U-shaped steel bars on both sides are welded in parallel. Among them, two sets of L-shaped steel plates symmetrically arranged at the bottom of the precast component form a mutual torque through U-shaped steel bars.

[0009] In the preferred embodiment, in step S3, two rows of steel pipe secondary ribs are erected in parallel within the bearing grooves of the precast components at both ends, and multiple square timber main ribs are erected vertically on the steel pipe secondary ribs. The comb plate template is laid on the square timber main ribs, and the grooved sections at both ends are aligned with the bearing grooves. The upper chord plate reinforcement is constructed on the comb plate template. The solid contact section of the comb plate template is fitted to the top surface of the precast component, and sealant is filled at the joint. During the construction phase, precast components bear the load of the formwork through a bearing groove.

[0010] In the preferred embodiment, the secondary steel pipe rib is composed of two parallel, welded circular steel pipes. After the reinforcing bars of the precast components pass through the grooved section of the comb plate template, the upper chord reinforcing bars are tied. A mid-span support steel pipe secondary rib is set at the mid-span position, with the upper end of the mid-span support abutting the middle of the steel pipe secondary rib, and a second concrete pad is set at the lower end.

[0011] In the preferred embodiment, in step S4, the elevation of the completed concrete pouring surface of the lower chord formwork is higher than the upper surface of the L-shaped steel plate, the first concrete pad, and the second concrete pad. A slope surface adapted to the L-shaped steel plate is cast, and the L-shaped steel plate is covered and connected to the lower chord concrete slab and precast components.

[0012] In the preferred embodiment, step S5 involves a two-stage dismantling operation: Phase 1 Demolition: When the concrete strength reaches 75% of the design strength, remove the mid-span uprights but retain them so that they can proceed to the next construction phase, while retaining the secondary steel pipe joists; Second stage of demolition: When the concrete strength reaches 100% of the design strength, the formwork system and all auxiliary supports are removed.

[0013] In the preferred embodiment, the method for determining the concrete strength includes: preparing standard concrete cube specimens on-site and curing them under the same conditions, and determining the standard values ​​of compressive strength at 7d, 14d, and 28d. The rebound method was used simultaneously to test the interface between the precast and cast-in-place components and the area surrounding the bearing groove. The rebound results were cross-validated with the strength of test blocks under the same conditions to ensure the accuracy of the strength data.

[0014] In the preferred embodiment, the filling method of the bearing groove is as follows: after removing the auxiliary support, clean the debris and laitance in the groove, wet the groove body and pour micro-expansion fine stone concrete, cover and cure for 14 days after filling, and after the strength reaches the standard, trim the surface to be flush with the side of the precast component.

[0015] This invention provides a construction method for converting temporary support of precast concrete components into a permanent load-bearing system, significantly reducing the amount of traditional steel pipe supports used. The load-bearing groove at the top of the precast component directly bears the formwork load, replacing the densely arranged upright supports of the original design. The precast components are manufactured in a factory according to standardized dimensions, avoiding the need for frequent adjustments to the upright height due to changes in curvature on site, reducing the total amount of reusable materials such as steel pipes, and minimizing reliance on temporary support systems.

[0016] In terms of saving material costs, the standardized production of prefabricated components avoids the waste caused by differences in pole heights in traditional processes, which result in a large number of steel pipes that cannot be reused. With the simplification of the support system, the amount of auxiliary materials such as main and secondary steel pipe ribs is reduced accordingly, improving resource turnover and overall economic efficiency.

[0017] Construction conditions have significantly improved. The reduced number of support poles has increased the clear space on the work surface, improving the efficiency of personnel passage and material transportation. The increased operating space for key processes such as concrete pouring has reduced construction interference and accelerated the overall progress. The concrete spacers and L-shaped steel plate fixing devices installed within the reinforcement intervals of the lower chord slab provide a stable foundation for the precast components, reducing the difficulty of on-site leveling.

[0018] Positioning accuracy is significantly improved. Precise control of the precast component's hoisting position is achieved through positioning lines, combined with the counteracting torque mechanism of the L-shaped steel plate and U-shaped reinforcing bars, realizing bidirectional rigid constraint at the bottom of the precast component. This fixing method overcomes the risk of welding asymmetry, ensuring that the precast component is installed without deflection, and eliminating the potential for cracks or deformation caused by eccentric loading at its source.

[0019] The overall structural integrity is significantly enhanced. After the precast components bear construction loads through the load-bearing grooves, they form a rigid connection with the cast-in-place upper and lower chord slabs through layered casting. Once the concrete reaches the required strength, the auxiliary supports are removed, and the precast components and the cast-in-place structure together constitute a continuous force transmission system. The load-bearing grooves are filled with micro-expansion concrete to form a complete cross-section, thus transforming the precast components from temporary supports into permanent structural components. This dynamic conversion mechanism optimizes the moment and shear force transmission paths of the curved arch slab, improving structural durability and seismic performance. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a structural diagram of the prefabricated components of the present invention; Figure 2 This is a structural diagram of the auxiliary support of the present invention; Figure 3 This is a structural diagram of the comb plate template erection structure of the present invention; Figure 4 This is a diagram of the steel reinforcement binding structure of the present invention; Figure 5 This is a structural diagram of the concrete casting slab of the present invention; Figure 6 This is a structural diagram of the arch plate after the bracket of the present invention has been removed; Figure 7 This is a diagram of the L-shaped steel plate installation structure in Embodiment 2 of the present invention; Figure 8 This is a side view of the L-shaped steel plate installation structure in Embodiment 2 of the present invention; Figure 9 This is a diagram of the connection structure of any group of L-shaped steel plates in Embodiment 2 of the present invention; Figure 10 This is a typical cross-sectional view of the arc-shaped arch plate of the present invention.

[0021] In the diagram: 1. Precast component; 101. Bearing groove; 2. Secondary steel pipe rib; 3. Comb plate template; 301. Groove section; 4. Lower chord template foundation; 401. Main steel pipe rib; 402. Secondary square timber rib; 5. Lower chord template; 6. Lower chord plate reinforcement; 7. First concrete pad; 701. Through hole; 8. L-shaped steel plate; 9. U-shaped reinforcement; 10. Main square timber rib; 11. Upper chord plate reinforcement; 12. Mid-span upright; 13. Second concrete pad. Detailed Implementation

[0022] Example 1 like Figure 1-6 As shown in Figure 10, a construction method for converting temporary support of precast concrete components into a permanent load-bearing system includes: S1. Precast concrete components according to the curvature of the arc-shaped arch plate in the factory, with a rectangular bearing groove 101 reserved at the top; S2. Hoist the precast component 1 to the designed position and form a lateral clamping constraint through the lower fixing device; S3. Install the secondary steel pipe rib 2 in the bearing groove 101, and lay the matching comb plate template 3 on the top of the secondary steel pipe rib 2 so that its bottom surface is in contact with the top surface of the precast component 1. S4. Pour the concrete around the upper and lower chords and precast component 1 in layers to make precast component 1 and cast-in-place structure form an integral whole; S5. As the concrete strength increases, the auxiliary supports are gradually removed to complete the transfer of load to precast component 1; S6. Remove the secondary steel pipe rib 2 and the comb plate template 3, fill the bearing groove 101, and form a continuous stress section; In the construction phase, the precast component 1 bears the load of the formwork through the bearing groove 101, and in the service phase, it participates in the permanent bearing of the structure through the filled continuous section, thereby realizing the transformation of the dynamic force system.

[0023] This application achieves the system transformation from temporary support to permanent load-bearing through a three-stage progressive force transfer: Phase 1: Temporary Support Phase: From formwork installation to completion of concrete pouring.

[0024] The precast component 1 receives the load of the segmented bottom formwork and the newly poured concrete through the upper bearing groove 101, and the vertical displacement is restricted by the high-strength concrete pad at the bottom; the lateral displacement is restricted by the L-shaped steel plates 8 on both sides, forming a temporary support system with precast components as the main component and a small number of lightweight auxiliary supports as the auxiliary components, replacing the traditional dense steel pipe support.

[0025] Phase 2: Load transfer phase: Concrete curing period.

[0026] As the concrete strength increases, the auxiliary supports are gradually removed. The load is gradually transferred through the bearing groove 101 of the precast component 1 → precast component 1 → lower chord plate, so that the force on the precast component 1 smoothly transitions from local support to overall bearing, adapting to the curved force characteristics of the arched plate.

[0027] Phase 3: Permanent load-bearing phase, from demolding to the structural service life.

[0028] The precast component 1 and the upper and lower chords are integrally cast with concrete to form a rigid whole, which together resists the bending moment, shear force and axial force of the arched slab. The upper bearing groove 101 is filled with micro-expansion fine stone concrete, forming a continuous section with the precast component 1, completing the complete transformation from a temporary support component to a permanent structural component.

[0029] In the preferred embodiment, in step S1, the bearing groove 101 is spaced along the length of the arc-shaped arch plate, and the spacing is set to be no greater than the original design pole spacing. The bottom elevation of the bearing trough 101 is set such that after the secondary steel pipe ribs 2 are installed, the alignment of the comb-tooth plate template 3 matches the curvature of the arc-shaped arch plate. This avoids template deformation and grout leakage, and eliminates the need for on-site leveling.

[0030] The construction of curved arch slabs requires the erection of dense steel pipe supports with small spacing between the uprights to accommodate the differences in formwork height caused by curvature changes. The essence of the solution in this application is to use precast components 1 to replace the vertical support function without separate uprights. The traditional upright spacing is determined by the calculation of formwork stiffness and concrete pouring load. Therefore, the bearing groove 101, which is the main load-bearing part, needs to be replaced and calculated according to the original multi-upright design. After the bearing groove 101 and auxiliary support structure replace some of the uprights, only a small number of mid-span auxiliary supports need to be retained.

[0031] In the preferred embodiment, step S2 includes: S21. Erect the lower chord formwork foundation 4, which consists of steel pipe main beams 401 and square timber secondary beams 402, and lay the lower chord formwork 5 on the foundation. S22. Tie the lower chord plate reinforcement 6 on the lower chord formwork 5, and pop up the positioning line of the precast component 1 according to the structural force transmission path design position. S23. Hoist the precast component 1 into the positioning line of the lower chord template 5, and place it on the first concrete pad 7 within the interval of the lower chord plate reinforcement 6. S24. L-shaped steel plates 8 are symmetrically arranged on both sides of the precast component 1, so that their vertical sides are closely attached to the bottom side surface of the precast component 1, and their horizontal sides are welded and fixed to the lower chord plate steel bars 6.

[0032] The design location of precast component 1 is a balance point between mechanical performance and construction feasibility. It not only meets the overall stress requirements of the arched slab, but also provides a clear benchmark for on-site hoisting and solves the problem of eccentric loading.

[0033] In the preferred embodiment, in step S3, two rows of steel pipe secondary ribs 2 are erected in parallel within the bearing grooves 101 of the precast components 1 at both ends, and multiple square timber main ribs 9 are erected vertically on the steel pipe secondary ribs 2. The comb plate template 3 is laid on the square timber main ribs 9, and its two end groove sections 301 are aligned with the bearing grooves 101. The upper chord plate reinforcement 10 is constructed on the comb plate template 3. The solid contact section of the comb plate template 3 is fitted with the top surface of the precast component 1, and the joint is filled with sealant. Among them, the precast component 1 bears the load of the formwork through the bearing groove 101 during the construction stage.

[0034] In the preferred embodiment, the secondary steel pipe rib 2 is composed of two parallel, welded circular steel pipes; The reinforcing bars of precast component 1 are tied to the upper chord reinforcing bars after passing through the groove section 301 of the comb plate template 3; A mid-span upright 11 is installed at the mid-span position to support the secondary steel pipe rib 2. The upper end of the mid-span upright 11 abuts against the middle of the secondary steel pipe rib 2, and the lower end is provided with a second concrete pad 12.

[0035] In this scheme, the width of the groove section 301 of the comb plate template 3 is matched with the secondary steel pipe rib 2. The template is laid to cover the secondary steel pipe rib 2, and the groove depth is determined by the thickness of the secondary steel pipe rib 2 and the template.

[0036] In this embodiment, two spliced ​​φ48×3.5mm circular steel pipes are used as secondary ribs. When it is necessary to support curved templates or deal with uneven foundations, the circular pipes have a certain degree of flexibility, which can adapt to the slight undulations or curvature of the template panel to a certain extent, improve the bending stiffness, and the moment of inertia of their parallel combined section will be significantly larger than that of a single circular pipe, which can better ensure the flatness of the concrete structure.

[0037] In the preferred embodiment, in step S4, the elevation of the completed concrete pouring surface of the lower chord formwork is higher than the upper surface of the horizontal plate of the L-shaped steel plate 8, the first concrete pad 7, and the second concrete pad 12. A slope surface adapted to the L-shaped steel plate 8 is poured, and the L-shaped steel plate 8 is covered and the lower chord concrete pouring slab is connected to the precast component 1.

[0038] In the preferred embodiment, step S5 involves a two-stage dismantling operation: Phase 1 Demolition: When the concrete strength reaches 75% of the design strength, remove the central upright 11 and retain it so that it can proceed to the next construction phase, while retaining the secondary steel pipe purlin 2. Second stage of demolition: When the concrete strength reaches 100% of the design strength, the formwork system and all auxiliary supports are removed.

[0039] According to GB50666-2011 "Code for Construction of Concrete Structures". Once the concrete strength reaches 75% of the design strength, the mid-span upright 11 will be removed, and the construction process will proceed to the next span. The upper horizontal members will be retained. The bottom formwork and supports should be removed after the concrete strength reaches the design requirements. When there are no specific design requirements, the compressive strength of concrete cube specimens cured under the same conditions should meet the requirements in the table below, and this should be used to confirm that the concrete strength requirement for removal in the first stage in this embodiment is 75%.

[0040] Table 1 Concrete strength requirements during bottom formwork removal

[0041] In the preferred embodiment, the method for determining the concrete strength includes: preparing standard cubic concrete specimens with dimensions of 150mm×150mm×150mm on site, curing them under the same conditions, and determining the standard values ​​of compressive strength at 7d, 14d, and 28d. The rebound method was used simultaneously to test the interface between the precast component 1 and the cast-in-place part, as well as the area surrounding the bearing groove 101. The rebound results were cross-validated with the strength of test blocks under the same conditions to ensure the accuracy of the strength data.

[0042] In the preferred embodiment, the filling method of the bearing groove 101 is as follows: after removing the auxiliary support, clean the debris and laitance in the groove, wet the groove body and pour micro-expansion fine stone concrete, cover and cure for 14 days after filling, and after the strength reaches the standard, trim the surface to be flush with the side of the precast component 1.

[0043] Example 2 Further explanation in conjunction with Example 1, such as Figure 7-9 The structure shown includes step S2 as follows: S21. Erect the lower chord formwork foundation 4, which consists of steel pipe main beams 401 and square timber secondary beams 402, and lay the lower chord formwork 5 on the foundation. S22. Tie the lower chord plate reinforcement 6 on the lower chord formwork 5, and pop up the positioning line of the precast component 1 according to the structural force transmission path design position. S23. Set a first concrete pad 7 with through holes 701 in the positioning line, and prepare an L-shaped steel plate 8 with U-shaped steel bars 801 connected to the end, wherein the extension direction of the U-shaped steel bars 801 points to the back side of the vertical plate of the L-shaped steel plate 8. S24. Hoist the precast component 1 into the positioning line of the lower chord formwork 5 and place it on the first concrete pad 7. S25. A symmetrical L-shaped steel plate 8 is set on both sides of the precast component 1, so that its vertical side is closely attached to the bottom side surface of the precast component 1. A U-shaped steel bar 801 passes through the through hole 701 in the middle of the first concrete pad 7 from below the lower chord plate steel bar 6 and extends to a distance to the front end of the horizontal side of the L-shaped steel plate 8 on the opposite side. The extended parts of the U-shaped steel bars 801 on both sides are welded in parallel. Among them, two sets of L-shaped steel plates 8 symmetrically arranged at the bottom of the precast component 1 form a mutual torque through U-shaped steel bars 801.

[0044] In Example 1, the L-shaped steel plate 8 needs to be welded to the lower chord plate reinforcement 6 on site. Due to the asymmetry of the weld points, the bearing force on the precast component 1 is uneven. There are many weld points to be constructed, the construction space is small, and the construction angle is small, which consumes labor costs and has low construction efficiency.

[0045] In this embodiment, U-shaped steel bar 801 is used as the extension of L-shaped steel plate 8. The angle between its U-shaped structure and the plane is set according to the interval between the lower chord plate steel bar 6 and the lower chord template 5. It is positioned and bidirectionally connected through the through hole 701 of the first concrete pad 7, and then welded together after pre-tightening. The welding point processing only requires processing several parallel points through the interval of the lower chord plate steel bar 6.

[0046] Because the fixed connection point between the U-shaped steel bar 801 and the L-shaped steel plate 8 is off-center, the welded tie at the other end will generate a torque on the L-shaped steel plate 8. Therefore, the U-shaped steel bar 801 at the bottom corner on the other side of the precast component 1 needs to be reversed to generate the opposite torque and prevent the precast component 1 from deflecting.

[0047] The self-weight of the precast component 1 and the load it bears exert a large pressure on the first concrete pad 7, which can prevent it from deflecting, thereby further fixing the two U-shaped steel bars 801 that pass through its middle and enhancing the stability of the support structure.

[0048] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A construction method for converting temporary support of precast concrete components into a permanent load-bearing system, characterized by: The method includes: S1. Precast concrete components in the factory according to the curvature of the arc-shaped arch plate, with a rectangular bearing groove (101) reserved at the top. S2. Hoist the precast component (1) to the design position and form a lateral clamping constraint through the lower fixing device; S3. Install steel pipe secondary ribs (2) in the bearing groove (101) and lay a suitable comb plate template (3) on the steel pipe secondary ribs (2) so that its bottom surface is in contact with the top surface of the precast component (1); S4. Pour the concrete around the upper and lower chords and precast components (1) in layers to make the precast components (1) and the cast-in-place structure form an integral whole. S5. As the concrete strength increases, the auxiliary support is gradually removed to complete the transfer of load to the precast component (1); S6. Remove the secondary steel pipe ribs (2) and the comb plate template (3), fill the bearing groove (101), and form a continuous stress section; In the construction stage, the precast component (1) bears the load of the template through the bearing groove (101), and in the use stage, it participates in the permanent bearing of the structure through the continuous section after filling, so as to realize the transformation of the dynamic force system.

2. The construction method for a precast concrete component temporary support to permanent load-bearing system according to claim 1, characterized in that: In step S1, the bearing groove (101) is set at intervals along the length of the arc-shaped arch plate, and the interval is set to be no greater than the original design pole spacing; The bottom elevation of the bearing groove (101) is set as follows: after the steel pipe secondary rib (2) is installed, the line shape of the comb plate template (3) matches the curvature of the arc arch plate.

3. The construction method for converting temporary support to permanent load-bearing system of precast concrete components according to claim 1, characterized in that: step S2 includes: S21. Erect a lower chord formwork foundation (4) consisting of a main steel pipe joist (401) and a secondary square timber joist (402), and lay the lower chord formwork (5) on the foundation. S22. Tie the lower chord plate reinforcement (6) on the lower chord template (5) and pop up the positioning line of the precast component (1) according to the structural force transmission path design position; S23. Hoist the precast component (1) into the positioning line of the lower chord formwork (5) and place it on the first concrete pad (7) in the interval of the lower chord plate reinforcement (6); S24. A L-shaped steel plate (8) is symmetrically set on both sides of the precast component (1), so that its vertical side is closely attached to the bottom side surface of the precast component (1), and its horizontal side is welded and fixed to the lower chord plate reinforcement (6).

4. The construction method for converting temporary support to permanent load-bearing system of precast concrete components according to claim 1, characterized in that: step S2 includes: S21. Erect a lower chord formwork foundation (4) consisting of a main steel pipe joist (401) and a secondary square timber joist (402), and lay the lower chord formwork (5) on the foundation. S22. Tie the lower chord plate reinforcement (6) on the lower chord template (5) and pop up the positioning line of the precast component (1) according to the structural force transmission path design position; S23. Set a first concrete pad (7) with a through hole (701) inside the positioning line, and prepare an L-shaped steel plate (8) with U-shaped steel bars (801) at the end, wherein the extension direction of the U-shaped steel bars (801) points to the back side of the vertical plate of the L-shaped steel plate (8). S24. Hoist the precast component (1) into the positioning line of the lower chord template (5) and place it on the first concrete pad (7); S25. On both sides of the precast component (1), L-shaped steel plates (8) are symmetrically arranged so that their vertical sides are closely attached to the bottom side surface of the precast component (1). U-shaped steel bars (801) pass through the through hole (701) in the middle of the first concrete pad (7) from below the lower chord steel bar (6) and extend to the front end of the horizontal side of the L-shaped steel plate (8) on the opposite side. The extended parts of the U-shaped steel bars (801) on both sides are welded in parallel. Among them, two sets of L-shaped steel plates (8) symmetrically arranged at the bottom of the precast component (1) form a mutual torque through U-shaped steel bars (801).

5. The construction method for a temporary support to permanent load-bearing system for precast concrete components according to claim 1, characterized in that: In step S3, two rows of steel pipe secondary joists (2) are erected in parallel in the bearing groove (101) of the precast components (1) at both ends, and multiple square timber main joists (9) are erected vertically on the steel pipe secondary joists (2). The comb plate template (3) is laid on the square timber main joists (9), and its two end groove sections (301) are aligned with the bearing groove (101). The upper chord plate reinforcement (10) is constructed on the comb plate template (3). The solid contact section of the comb plate template (3) is attached to the top surface of the precast component (1), and the joint is filled with sealant. In this process, the precast component (1) receives the formwork load through the bearing groove (101) during the construction phase.

6. The construction method for a temporary support to permanent load-bearing system for precast concrete components according to claim 5, characterized in that: The secondary steel pipe (2) is composed of two parallel, welded circular steel pipes; The reinforcing bars of the precast component (1) are tied to the upper chord reinforcing bars after passing through the groove section (301) of the comb plate template (3); A mid-span upright (11) is set at the mid-span position to support the secondary steel pipe rib (2). The upper end of the mid-span upright (11) abuts against the middle of the secondary steel pipe rib (2), and the lower end is set with a second concrete pad (12).

7. The construction method for a precast concrete component temporary support to permanent load-bearing system according to claim 1, characterized in that: In step S4, the elevation of the concrete pouring completed surface of the lower chord formwork is higher than the upper surface of the horizontal plate of the L-shaped steel plate (8), the first concrete pad (7), and the second concrete pad (12). A slope surface adapted to the L-shaped steel plate (8) is poured, the L-shaped steel plate (8) is covered, and the lower chord concrete pouring slab is connected to the precast component (1).

8. The construction method for a temporary support to permanent load-bearing system for precast concrete components according to claim 1, characterized in that: In step S5, the dismantling operation is performed in two stages: First stage of demolition: When the concrete strength reaches 75% of the design strength, the mid-span upright (11) is demolished and retained so that it can proceed to the next construction phase, while the secondary steel pipe joists (2) are retained. Second stage of demolition: When the concrete strength reaches 100% of the design strength, the formwork system and all auxiliary supports are removed.

9. The construction method for a precast concrete component temporary support to permanent load-bearing system according to claim 8, characterized in that: concrete... The methods for judging strength include: making standard concrete cube specimens on site and curing them under the same conditions, and measuring the standard values ​​of compressive strength at 7d, 14d, and 28d. The rebound method was used simultaneously to test the interface between the precast component (1) and the cast-in-place part, as well as the area around the bearing groove (101). The rebound results were cross-validated with the strength of the test block under the same conditions to ensure the accuracy of the strength data.

10. The construction method for a precast concrete component temporary support to permanent load-bearing system according to claim 1, characterized in that: The filling method of the bearing groove (101) is as follows: after removing the auxiliary support, clean the debris and laitance in the groove, wet the groove body and pour micro-expansion fine stone concrete, cover and cure for 14 days after filling, and after the strength reaches the standard, trim the surface to be flush with the side of the precast component (1).

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