A water area concrete rigid frame bridge suspension formwork support and a construction method thereof

Abstract

The application is a kind of water area concrete rigid frame bridge suspension formwork support and its construction method, including a plurality of steel pipe columns, the steel pipe column is arranged on the top of the bridge pier column, the top of the bridge pier column is provided with a cast-in-situ box girder, the bottom of the cast-in-situ box girder is provided with a box girder bottom die, the top of the box girder bottom die is provided with a weight block at both ends, the weight block is located on the left and right sides of the cast-in-situ box girder, the bottom of the box girder bottom die is provided with a plurality of suspension frames, the top of the suspension frame is connected with a guardrail at both ends, the guardrail is located on the front and rear sides of the cast-in-situ box girder, the steel pipe column and the suspension frame are connected through a cable, and a transverse support is connected between the adjacent steel pipe columns on the front and rear sides. The application has the advantages of simple structure, convenient and fast installation and removal, small amount of field welding, less water surface operation, short construction period, high safety of worker construction, small amount of steel, and the rest part can be reused except the first steel pipe column, which does not affect the traffic passing under the cantilever; wide applicability, high turnover utilization rate of the support, and good economy.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering construction technology, and in particular to a suspended formwork support for a rigid concrete frame bridge over water and its construction method. Background Technology

[0002] A rigid-frame concrete bridge is a type of bridge structure where the superstructure and piers are rigidly connected as a whole. Because rigid-frame concrete bridges do not require supports, the effects of water level fluctuations, tides, and splashes on the supports do not need to be considered. Small-span rigid-frame concrete bridges are frequently used in bridges in high-water areas and in park waterfront walkways. The conventional construction method for the superstructure of a rigid-frame concrete bridge in water areas typically involves driving steel pipe piles and erecting Bailey bridge supports and steel distribution beams as the bottom formwork and pouring platform for the superstructure. However, this method has the following technical problems:

[0003] 1. The process of driving steel pipe piles, erecting Bailey beams and dismantling them is complicated, inconvenient and time-consuming.

[0004] 2. After the box girder is poured, the support is difficult to dismantle and is easily damaged, resulting in low formwork turnover rate;

[0005] 3. The steel pipe piles and Bailey beam supports require a large amount of steel, and the steel pipe piles directly under the box girder cannot be pulled out after the box girder is poured. The only option is to cut off the part above water, which results in material waste and poor economic efficiency.

[0006] 4. The amount of welding on-site during structural installation and dismantling is large, and the construction work is highly dangerous for workers.

[0007] In view of the above-mentioned shortcomings of existing methods, there is an urgent need to propose effective solutions. Summary of the Invention

[0008] The present invention aims to address the shortcomings of the prior art by providing a suspended formwork support for a rigid concrete frame bridge over waterways and its construction method.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: a suspended formwork support for a rigid concrete frame bridge in water area, comprising several steel pipe columns, which are located on top of bridge piers. A cast-in-place box girder is located on top of the bridge piers, and a bottom formwork for the box girder is located at the bottom of the cast-in-place box girder. Weight blocks are located at both ends of the top of the bottom formwork for the box girder, and the weight blocks are located on the left and right sides of the cast-in-place box girder. Several suspension frames are located at the bottom of the bottom formwork for the box girder, and guardrails are connected to the front and rear ends of the top of the suspension frames. The guardrails are located on the front and rear sides of the cast-in-place box girder. The steel pipe columns and the suspension frames are connected by cables, and lateral supports are connected between adjacent steel pipe columns on the front and rear sides.

[0010] Furthermore, the steel pipe column includes a first steel pipe column, which is located inside the cast-in-place box girder and has the same height as the cast-in-place box girder. The first steel pipe column and the bridge pier column are connected by embedded parts. A second steel pipe column is connected to the top of the first steel pipe column, and the first and second steel pipe columns are connected by flanges. Several first ear plates are connected to the upper left and right sides of the second steel pipe column, and the steel pipe column and the cable are connected through the first ear plates. Two second ear plates are connected to the upper front and rear sides of the second steel pipe column, and the second steel pipe column and the transverse support are connected through the second ear plates.

[0011] Furthermore, the suspension frame includes several crossbeams, with lifting lugs connected to the top of the crossbeams. The suspension frame and cables are connected through the lifting lugs. Several longitudinal beams are connected between adjacent crossbeams. Diagonal braces connect the crossbeams and longitudinal beams. The crossbeams near the bridge piers are connected to the bridge piers through clamps. Rubber pads are provided between the clamps and the bridge piers. The outer longitudinal beams are connected through a first connecting arm and a second connecting arm. The first connecting arm and the second connecting arm are connected through connecting flanges. The position of the first connecting arm corresponds to the bridge pier.

[0012] Furthermore, a sleeve is installed on the lower outer side of the cable, and the sleeve is located inside the cast-in-place box girder.

[0013] Furthermore, the lateral support includes two horizontal braces, with a scissor brace connecting the two horizontal braces. Both the horizontal braces and the scissor brace are connected to the second ear plate.

[0014] Furthermore, the cast-in-place box girder has several transverse main reinforcement bars and several longitudinal main reinforcement bars on both the upper and lower sides. The ends of the transverse main reinforcement bars and longitudinal main reinforcement bars of the cast-in-place box girder that are cut off by the first steel pipe column are welded to the first steel pipe column. The first steel pipe column and the casing are filled with post-cast concrete.

[0015] Furthermore, the suspension frame is a truss structure, with a longitudinal length that is half the span of a single span and a transverse width that is greater than the width of the cast-in-place box girder.

[0016] Furthermore, the crossbeams are closed box-shaped steel structure beams arranged transversely along the bridge, the longitudinal beams are closed box-shaped steel structure beams arranged longitudinally along the bridge, and the clamps are concave steel structures with the concave surface having the same diameter as the bridge pier column.

[0017] Furthermore, the buoyancy generated by the crossbeams and longitudinal beams is greater than the weight of the structure itself, allowing it to float on the water surface after the suspension frame is removed.

[0018] A construction method for a suspended formwork support for a rigid concrete frame bridge over waterways includes the following steps:

[0019] S1. Construct trestle bridges and platforms, build bridge pile foundations and bridge piers, and pre-embed embedded parts for connecting the first steel pipe column on the top surface of the bridge piers when pouring the concrete. The embedded parts are set inside the main reinforcement of the pier.

[0020] S2. Prefabricate steel pipe columns, suspension frames, cables, lateral supports, counterweights, and box girder bottom formwork in the factory and transport them to the site;

[0021] S3. Install the first steel pipe column, the second steel pipe column, and the transverse support in sequence;

[0022] S4. Install the suspension frame and cables to form a stable suspension structure. The suspension frame is tightened to the bridge piers with clamps. When installing the cables, sleeves are installed in advance at the part that passes through the cast-in-place box girder.

[0023] S5. Connect the first connecting arm and the second connecting arm to form a whole concrete rigid frame bridge suspension frame. Install guardrails on the outside of the suspension frame and install the bottom formwork of the box girder on the suspension frame.

[0024] S6. Tie the reinforcing bars on the bottom formwork platform of the box girder. For the transverse main bars and longitudinal main bars of the box girder that are cut off by the first steel pipe column, weld the end hooks of the reinforcing bars to the outer wall of the first steel pipe column.

[0025] S7. When pouring the cast-in-place box girder concrete, add counterweights evenly at both ends of the suspension frame simultaneously during the pouring process.

[0026] S8. After the cast-in-place box girder concrete reaches the design strength, unload the counterweight and disconnect the connection between the first connecting arm and the second connecting arm.

[0027] S9. Sequentially disconnect the cable of each suspension frame from the first ear plate, lower the entire suspension frame until it floats on the water surface, and then drag the suspension frame out from the side of the bridge along the water surface;

[0028] S10. Remove the second steel pipe column and the transverse support, and pour the post-concrete inside the first steel pipe column and the casing.

[0029] S11. Construct bridge deck paving and ancillary facilities, and complete the construction of a single concrete rigid frame bridge;

[0030] S12. Install the dismantled steel pipe columns, suspension frames, cables, transverse supports, and box girder bottom formwork onto the second section of the concrete rigid frame bridge. Repeat the above steps to construct the next section of the concrete rigid frame bridge.

[0031] The beneficial effects of this invention are: the structure of this invention is simple, requiring no steel pipe piles or other complex structures, and is convenient and quick to install and dismantle. All components are connected by hinges or bolts, resulting in less on-site welding, less water surface work, a short construction period, and high worker safety. The support is a suspended structure, requiring less steel, and except for the first steel pipe column, the rest can be reused without affecting traffic flow on the road below the cantilever. It has wide applicability, high support turnover rate, and good economic efficiency. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the present invention;

[0033] Figure 2 This is a cross-sectional view of the present invention;

[0034] Figure 3 This is a plan view of the suspension frame in this invention;

[0035] Figure 4 This is a schematic diagram of the steel pipe column in this invention;

[0036] Figure 5 This is a longitudinal connection diagram of the steel pipe column, bridge pier column, and cast-in-place box girder in this invention;

[0037] Figure 6 This is a transverse connection diagram of the steel pipe column, bridge pier column, and cast-in-place box girder in this invention;

[0038] In the diagram: 11-Steel pipe column; 111-First steel pipe column; 112-Second steel pipe column; 1121-First ear plate; 1122-Second ear plate; 113-Embedded part; 114-Flange; 12-Suspension frame; 121-Crossbeam; 1211-Lifting lug; 122-Longitudinal beam; 123-Diagonal brace; 124-Clamping clamp; 125-Rubber pad; 126-First connecting arm; 127-Second connecting arm; 13-Cable; 14-Transverse support; 141-Horizontal brace; 142-Scissor brace; 15-Counterweight block; 16-Box girder bottom formwork; 17-Bridge pier column; 171-Pier column main reinforcement; 18-Cast-in-place box girder; 181-Post-cast concrete; 182-Box girder transverse main reinforcement; 183-Box girder longitudinal main reinforcement; 19-Water surface; 20-Guardrail;

[0039] The following will describe in detail, with reference to the accompanying drawings, embodiments of the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to embodiments:

[0041] like Figures 1-6As shown, a suspended formwork support for a rigid concrete frame bridge in water area includes several steel pipe columns 11, which are installed on top of bridge piers 17. A cast-in-place box girder 18 is positioned on top of the bridge piers 17, and a box girder bottom formwork 16 is provided at the bottom of the cast-in-place box girder 18. Weight blocks 15 are located at both ends of the top of the box girder bottom formwork 16, situated on the left and right sides of the cast-in-place box girder 18. Several suspension frames 12 are provided at the bottom of the box girder bottom formwork 16, with guardrails 20 connected to the front and rear ends of the top of the suspension frames 12, located on the front and rear sides of the cast-in-place box girder 18. The steel pipe columns 11 and the suspension frames 12 are connected by cables 13, and lateral supports 14 connect adjacent steel pipe columns 11 on the front and rear sides. The steel pipe columns 11 include a first steel pipe column 111, which is installed inside the cast-in-place box girder 18 and is not removed after being cast inside the cast-in-place box girder 18. The first steel pipe column 111 is at the same height as the cast-in-place box girder 18. The first steel pipe column 111 and the bridge pier column 17 are connected by embedded parts 113. The top of the first steel pipe column 111 is connected to the second steel pipe column 112. The second steel pipe column 112 can be removed and reused after the cast-in-place box girder 18 is poured. The first steel pipe column 111 and the second steel pipe column 112 are connected by flanges 114. Several first ear plates 1121 are connected to the upper left and right sides of the second steel pipe column 112. The steel pipe column 11 and the cable 13 are connected by the first ear plates 1121. Two second ear plates 1122 are connected to the upper front and rear sides of the second steel pipe column 112. The second steel pipe column 112 and the transverse support 14 are connected by the second ear plates 1122.

[0042] The suspension frame 12 includes several crossbeams 121. The number of crossbeams 121 should be determined according to the span of the cast-in-place box girder 18 and the load size, and should not be less than two. The top of the crossbeams 121 is connected to the lifting lugs 1211. The suspension frame 12 and the cable 13 are connected through the lifting lugs 1211. Several longitudinal beams 122 are connected between adjacent crossbeams 121. The number of longitudinal beams 122 should be determined according to the width of the cast-in-place box girder 18 and the load size. The crossbeams 121 and longitudinal beams 122 are connected by diagonal braces 123 to enhance the overall stability of the suspension frame 12. The crossbeams 121 near the bridge pier 17 are connected to the bridge pier 17 through clamps 124. Rubber pads 125 are provided between the clamps 124 and the bridge pier 17. The outer longitudinal beams 12 are connected through a first connecting arm 126 and a second connecting arm 127. The first connecting arm 126 and the second connecting arm 127 are connected through connecting flanges respectively. The position of the first connecting arm 126 corresponds to that of the bridge pier 17. The suspension frame 12 is a truss structure. Its longitudinal length is half the span of a single bridge, and its transverse width is greater than the width of the cast-in-place box girder 18. The crossbeam 121 is a closed box-shaped steel structure beam arranged transversely along the bridge, and the longitudinal beam 122 is a closed box-shaped steel structure beam arranged longitudinally along the bridge. The clamp 124 is a concave steel structure, with its concave surface having the same diameter as the bridge pier 17. The buoyancy generated by the crossbeams 121 and 122 is greater than the structure's own weight, allowing the suspension frame 12 to float on the water surface 19 after removal. The suspension frame 12 is used to bear all loads during the casting of the box girder bottom formwork 16 and the cast-in-place box girder 18.

[0043] A sleeve 131 is installed on the lower outer side of the cable 13. The sleeve 131 is located inside the cast-in-place box girder 18. The sleeve 131 prevents the cable 13 from being cast together with the cast-in-place box girder 18 and thus unable to be removed. The cable 13 effectively transfers the load on the suspension frame 12 to the steel pipe column 11. The transverse support 14 includes two horizontal braces 141, and a scissor brace 142 connects the two horizontal braces 141. Both the horizontal brace 141 and the scissor brace 142 are connected to the second ear plate 1122. The transverse support 14 enhances the overall transverse stability of the steel pipe column 11. Several transverse main reinforcement bars 182 and several longitudinal main reinforcement bars 183 are provided on the upper and lower sides of the cast-in-place box girder 18. The ends of the transverse main reinforcement bars 182 and the longitudinal main reinforcement bars 183 of the cast-in-place box girder 18, which are cut off by the first steel pipe column 111, are welded to the first steel pipe column 111. Post-cast concrete 181 is provided inside the first steel pipe column 111 and inside the sleeve 131.

[0044] A construction method for a suspended formwork support for a rigid concrete frame bridge over waterways includes the following steps:

[0045] S1. Construct trestle bridges and platforms, construct bridge pile foundations and bridge piers 17, and when pouring bridge piers 17, pre-embed pre-embedded parts 113 for connecting the first steel pipe column 111 on the top surface of the piers. The pre-embedded parts 113 are set inside the main reinforcement 171 of the piers.

[0046] S2. Prefabricate the steel pipe columns 11, suspension frames 12, cables 13, transverse supports 14, counterweights 15, and box girder bottom formwork 16 in the factory in advance and transport them to the site;

[0047] S3. Install the first steel pipe column 111, the second steel pipe column 112, and the transverse support 14 in sequence;

[0048] S4. Install the suspension frame 12 and the cable 13 to form a stable suspension structure. The suspension frame 12 is tightened to the bridge pier 17 by the clamp 124. When installing the cable 13, the sleeve 131 is installed in advance at the part that passes through the cast-in-place box girder 18.

[0049] S5. Connect the first connecting arm 126 and the second connecting arm 127 to form the entire concrete rigid frame bridge suspension frame 12 as a whole. Set up guardrail 20 on the outside of the suspension frame 12 and install box girder bottom formwork 16 on the suspension frame 12.

[0050] S6. Tie the reinforcing bars on the bottom formwork platform 16 of the box girder. For the transverse main reinforcing bars 182 and the longitudinal main reinforcing bars 183 of the box girder that are cut off by the first steel pipe column 111, weld the end hooks of the reinforcing bars to the outer wall of the first steel pipe column 111.

[0051] S7. Pour concrete for the cast-in-place box girder 18, and simultaneously and evenly add counterweight blocks 15 to the suspension frames 12 at both ends during pouring;

[0052] S8. After the concrete of the cast-in-place box girder 18 reaches the design strength, unload the counterweight block 15 and disconnect the connection between the first connecting arm 126 and the second connecting arm 127.

[0053] S9. Sequentially disconnect the cable 13 of each suspension frame 12 from the first ear plate 1121, lower the suspension frame 12 as a whole until it floats on the water surface 19, and then drag the suspension frame 12 out from the side of the bridge along the water surface 19.

[0054] S10. Remove the second steel pipe column 112 and the transverse support 14, and pour the post-concrete 181 inside the first steel pipe column 111 and the sleeve 131.

[0055] S11. Construct bridge deck paving and ancillary facilities, and complete the construction of a single concrete rigid frame bridge;

[0056] S12. Install the dismantled steel pipe column 11, suspension frame 12, cable 13, transverse support 14, and box girder bottom formwork 16 onto the second section of the concrete rigid frame bridge. Repeat the above steps to carry out the construction of the next section of the concrete rigid frame bridge.

[0057] The present invention has been described above by way of example. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or direct application to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A suspended formwork support for a rigid concrete frame bridge over waterways, characterized in that, It includes several steel pipe columns (11), the steel pipe columns (11) are located on the top of the bridge pier column (17), the top of the bridge pier column (17) is provided with a cast-in-place box girder (18), the bottom of the cast-in-place box girder (18) is provided with a box girder bottom formwork (16), the top two ends of the box girder bottom formwork (16) are provided with weight blocks (15), the weight blocks (15) are located on the left and right sides of the cast-in-place box girder (18), the bottom of the box girder bottom formwork (16) is provided with several suspension frames (12), the top front and rear ends of the suspension frames (12) are connected with guardrails (20), the guardrails (20) are located on the front and rear sides of the cast-in-place box girder (18), the steel pipe columns (11) and the suspension frames (12) are connected by cables (13), and the adjacent steel pipe columns (11) on the front and rear sides are connected by transverse supports (14). The steel pipe column (11) includes a first steel pipe column (111), which is located inside the cast-in-place box girder (18). The first steel pipe column (111) is at the same height as the cast-in-place box girder (18). The first steel pipe column (111) and the bridge pier column (17) are connected by embedded parts (113). The top of the first steel pipe column (111) is connected to a second steel pipe column (112). The first steel pipe column (111) and the second steel pipe column (112) are connected by flanges (114). Several first ear plates (1121) are connected to the upper left and right sides of the second steel pipe column (112). The steel pipe column (11) and the cable (13) are connected by the first ear plates (1121). Two second ear plates (1122) are connected to the upper front and rear sides of the second steel pipe column (112). The second steel pipe column (112) and the transverse support (14) are connected by the second ear plates (1122). The suspension frame (12) includes several crossbeams (121), with a lifting lug (1211) connected to the top of the crossbeam (121). The suspension frame (12) and the cable (13) are connected through the lifting lug (1211). Several longitudinal beams (122) are connected between adjacent crossbeams (121). The crossbeams (121) and longitudinal beams (122) are connected by a diagonal brace (123). The crossbeam (121) near the bridge pier (17) is connected to the bridge pier (17) through a clamp (124). A rubber pad (125) is provided between the clamp (124) and the bridge pier (17). The outer longitudinal beam (122) is connected through a first connecting arm (126) and a second connecting arm (127). The first connecting arm (126) and the second connecting arm (127) are connected through connecting flanges respectively. The position of the first connecting arm (126) corresponds to that of the bridge pier (17).

2. The suspended formwork support for a rigid concrete bridge over waterways according to claim 1, characterized in that, A sleeve (131) is installed on the lower outer side of the cable (13), and the sleeve (131) is located inside the cast-in-place box girder (18).

3. The suspended formwork support for a rigid concrete bridge over waterways according to claim 2, characterized in that, The lateral support (14) includes two horizontal braces (141), and a scissor brace (142) is connected between the two horizontal braces (141). Both the horizontal brace (141) and the scissor brace (142) are connected to the second ear plate (1122).

4. A suspended formwork support for a rigid concrete bridge over waterways according to claim 3, characterized in that, The cast-in-place box girder (18) has several transverse main reinforcement bars (182) and several longitudinal main reinforcement bars (183) on both the upper and lower sides. The ends of the transverse main reinforcement bars (182) and longitudinal main reinforcement bars (183) of the cast-in-place box girder (18) cut off by the first steel pipe column (111) are welded to the first steel pipe column (111). The first steel pipe column (111) and the sleeve (131) are filled with post-cast concrete (181).

5. A suspended formwork support for a rigid concrete bridge over waterways according to claim 4, characterized in that, The suspension frame (12) is a truss structure. The longitudinal length of the suspension frame (12) is half of the span of a single span, and the transverse width is greater than the width of the cast-in-place box girder (18).

6. A suspended formwork support for a rigid concrete bridge over waterways according to claim 5, characterized in that, The crossbeam (121) is a closed box-shaped steel structure beam set along the transverse direction of the bridge, the longitudinal beam (122) is a closed box-shaped steel structure beam set along the longitudinal direction of the bridge, and the clamp (124) is a concave steel structure with the concave surface having the same diameter as the bridge pier column (17).

7. A suspended formwork support for a rigid concrete bridge over waterways according to claim 6, characterized in that, The buoyancy generated by the crossbeam (121) and the longitudinal beam (122) is greater than the weight of the structure itself, and the suspension frame (12) can float on the water surface (19) after it is removed.

8. A construction method for a suspended formwork support for a rigid concrete frame bridge over waterways according to claim 7, characterized in that, Includes the following steps: S1. Construct a trestle bridge and platform, construct bridge pile foundations and bridge piers (17), and when pouring the bridge piers (17), pre-embed the pre-embedded parts (113) connecting the first steel pipe column (111) on the top surface of the piers in advance. The pre-embedded parts (113) are set inside the main reinforcement (171) of the pier. S2. Prefabricate steel pipe columns (11), suspension frames (12), cables (13), transverse supports (14), counterweights (15), and box girder bottom formwork (16) in the factory and transport them to the site; S3. Install the first steel pipe column (111), the second steel pipe column (112), and the transverse support (14) in sequence. S4. Install the suspension frame (12) and the cable (13) to form a stable suspension structure. The suspension frame (12) is tightened with the bridge pier (17) through the clamp (124). When installing the cable (13), the sleeve (131) is installed in advance in the part that passes through the cast-in-place box girder (18). S5. Connect the first connecting arm (126) and the second connecting arm (127) to form the whole concrete rigid frame bridge suspension frame (12). Set up guardrails (20) on the outside of the suspension frame (12) and install the box girder bottom formwork (16) on the suspension frame (12). S6. Tie the reinforcing bars on the bottom formwork (16) platform of the box girder. For the transverse main reinforcement (182) and longitudinal main reinforcement (183) of the box girder that are cut off by the first steel pipe column (111), weld the end hooks of the reinforcing bars to the outer wall of the first steel pipe column (111). S7. Pour concrete for cast-in-place box girder (18), and simultaneously and evenly add counterweights (15) to the suspension frames (12) at both ends during pouring. S8. After the concrete of the cast-in-place box girder (18) reaches the design strength, unload the counterweight block (15) and disconnect the connection between the first connecting arm (126) and the second connecting arm (127); S9. Sequentially disconnect the cable (13) of each suspension frame (12) from the first ear plate (1121), lower the suspension frame (12) as a whole until it floats on the water surface (19), and then drag the suspension frame (12) out from the side of the bridge along the water surface (19); S10. Remove the second steel pipe column (112) and the transverse support (14), and pour the post-cast concrete (181) inside the first steel pipe column (111) and the sleeve (131). S11. Construct bridge deck paving and ancillary facilities, and complete the construction of a single concrete rigid frame bridge; S12. Install the dismantled steel pipe column (11), suspension frame (12), cable (13), transverse support (14), and box girder bottom formwork (16) onto the second concrete rigid frame bridge. Repeat the above steps to carry out the construction of the next concrete rigid frame bridge.

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