Method for manufacturing a block for a small-radius flat curve steel box girder ramp bridge

Abstract

The application discloses a kind of small radius flat curve steel box girder ramp bridge block manufacturing method, it is related to bridge manufacturing technical field, it includes the following steps: S1: making sub-block scheme, the steel box girder ramp bridge to be manufactured is divided into unit, specific content is as follows;S101: longitudinal division is carried out, forms multiple segments, end support and middle support;S102: multiple segments are divided into transverse, when dividing, into cantilever and transverse sub-block, and transverse sub-block is located between two cantilevers;S2: segment is made using continuous matching manufacturing process, and flat curve precision and vertical curve precision control are carried out during manufacturing process;S3: segment is disintegrated, and the required block is obtained.The application solves the technical problems of unreasonable sub-block and large linear cumulative error of small radius flat curve steel box girder ramp bridge.

Description

Technical Field

[0001] This invention relates to the field of bridge manufacturing technology, and in particular to a method for manufacturing blocks for small-radius horizontal curve steel box girder ramp bridges. Background Technology

[0002] In recent years, with the rapid development of my country's transportation infrastructure construction and the increasing demands for the economic and environmental benefits of bridges throughout their entire life cycle, steel structure bridges have been widely promoted and applied due to their advantages such as high strength, light weight, short construction period, and recyclability. Since the release of relevant documents, the proportion of steel structure bridges, especially ramp bridge steel beams, used in new or expanded highway projects has increased significantly. These ramp bridge steel beams often need to adapt to complex track conditions, and their structures are often in a spatially twisted state with horizontal curves, vertical curves, and even pre-camber superposition. For relatively regular straight beams or large-radius curved beams, conventional manufacturing processes are already quite mature. Common practices include: dividing the beam into multiple manufacturing segments, using a "straight-to-curve" approach within each segment, that is, approximating the design curve with straight lines; or using 3D modeling for precise layout, unfolding the outline of each plate and reserving welding shrinkage before cutting, and then manufacturing in sections and assembling on site.

[0003] However, when the horizontal curve radius of a ramp bridge is too small (e.g., less than 300 meters), the beam structure is actually a complex structure formed by the superposition of multiple factors, including horizontal curves, vertical curves, pre-camber, and fixed cross slopes (such as the bridge deck cross slope achieved by rotating the entire box girder). When manufactured using existing conventional processes, problems often arise such as unreasonable segmentation leading to transportation or installation obstacles, large cumulative alignment errors, poor coordination between segments, large on-site trimming workload, long construction period, and high costs. Summary of the Invention

[0004] The purpose of this invention is to provide a method for manufacturing blocks for small-radius horizontal curve steel box girder ramp bridges, which solves the technical problems of unreasonable block division and large cumulative line error in existing technologies for small-radius horizontal curve steel box girder ramp bridges.

[0005] This application discloses a method for manufacturing blocks for small-radius horizontal curve steel box girder ramp bridges, characterized by the following steps: S1: Create a segmentation scheme, divide the steel box girder ramp bridge to be manufactured into units, the specific contents are as follows; S101: Divide longitudinally to form multiple segments, end supports, and middle supports; S102: Divide multiple segments laterally. During the division, divide them into cantilever arms and lateral blocks. The lateral blocks are located between two cantilever arms. S2: The segments are manufactured using a continuous matching process, and the accuracy of horizontal and vertical curves is controlled during the manufacturing process. S3: Disassemble the segment to obtain the desired block.

[0006] The manufacturing method of this application starts with the division of manufacturing units in the early stage. Taking into account factors such as avoiding wheel track lines, meeting the lifting capacity of complex sites and the rolling capacity of steel mills, and reducing welds in the support area, a reasonable division of manufacturing units is carried out. For the control of horizontal and vertical curves, a route of manufacturing the whole span and manufacturing the whole segment and then disassembling it is adopted to obtain the blocks to be assembled later.

[0007] Based on the above technical solution, the present application can be further improved as follows: Furthermore, when performing longitudinal division in step S101, the positive bending moment region at the mid-span of the continuous beam and the negative bending moment region at the pier top are avoided; The total width of the transverse blocks in step S102 does not exceed 5.3m. The beneficial effects of this step are used to make reasonable divisions, which facilitates subsequent production and manufacturing, reduces linear errors, and meets vehicle transportation requirements.

[0008] Furthermore, the specific content of step S2 is as follows: S201: Define the longitudinal and transverse baselines of the top and bottom plate units in each segment, and the longitudinal baselines between segments should be connected end to end; S202: Adopts solid bridge line assembly process, using the tire frame as the outer tire; S203: The longitudinal baseline extension of the intermediate block bottom plate unit of the segment located in the middle of the steel box girder ramp bridge is used as the longitudinal baseline of the whole bridge. The dimensional relationship between segments and the vertical curve direction of the whole bridge are controlled by controlling the dimensions between the transverse baselines of the intermediate block bottom plate units of each segment and the distance between the transverse baseline, the diaphragm position line and the crossbeam of the formwork. S204: Using the middle block base plate unit of the segment as a reference, locate and assemble the remaining base plate units within the segment; S205: Position and assemble the first partition unit. The web unit is made according to the curve and used as the inner tube to ensure that the bottom plate unit is in close contact with the frame. The cantilever block shape is based on the box body shape. Temporary connections are set at the joints to control its shape. Ground supports are set on the outside to ensure its stability. Finally, assemble the remaining partition and web units in sequence. S206: Vertical joint between the diaphragm unit and the web unit, and horizontal joint between the diaphragm unit and the bottom plate unit; S207: Using the top plate unit of the middle block of the segment as a reference, locate and assemble the remaining top plate units within the segment; S208: Transverse joint between the welded partition unit and the top plate unit, and longitudinal joint between the top plate unit and the web unit; S209: Repeat steps S204-S208 until all segments are completed. The advantage of this step is that it ensures the overall alignment accuracy of the bridge body with small-radius horizontal curves and superimposed vertical curves.

[0009] Furthermore, in step S201, the transverse baseline within each segment forms a straight line, perpendicular to the longitudinal baseline of the segment. The longitudinal baselines of the top and bottom plate units within each segment are parallel to each other. The advantage of this step is that it differs from conventional straight beam bridges, which arrange the longitudinal and transverse baseline network as a whole for the entire bridge and use a single benchmark to control assembly accuracy and alignment accuracy simultaneously. This step arranges the longitudinal and transverse baseline network as a whole for a single segment, which is more suitable for the accuracy control of curved beam bridges and reduces the difficulty of marking and assembly.

[0010] Furthermore, in step S202, the support frame is arranged as follows: the support plates are arranged according to the plane curve, with the longitudinal direction based on the partition unit close to the segment, and the transverse direction based on the support at the web unit of the segment and on both sides of the joint between two segments. The value is taken at each web of the segment according to the line shape after superimposed pre-arching, and the other positions can be taken by interpolation. The beneficial effect of this step is that it is more conducive to the value of the support plate height, and the support is at the structure, the beam is not easy to deform, and the line shape is more controllable.

[0011] Furthermore, in step S204, the lateral spacing between adjacent base plate units is the design value + 2mm. This step also includes the following: verifying the lateral baseline spacing between the outermost segments to ensure the overall horizontal curve accuracy is controllable; after confirming the measurement is correct, fixing the base plate unit to the jig; and simultaneously securing the longitudinal seam of the base plate unit without welding. The beneficial effect of this step is that it changes the existing practice of controlling the horizontal curve direction solely based on the lateral baseline spacing of the intermediate blocks, which leads to insufficient accuracy. By extending the lateral baseline to its maximum length and then measuring the distance between the two ends, the accuracy of the horizontal curve is guaranteed. Furthermore, in step S205, when the partition unit is cut, a 4mm-6mm wide slit is cut along the dividing line, and a butt joint bevel is pre-processed, resulting in a cutting area of ​​at least 260mm in total, to ensure the rigidity and integrity of the partition during transportation and assembly. For the partition in the cutting area, with the cutting line as the reference, a 1mm process allowance is left on each side of the width direction of the partition unit. The beneficial effect of this step is that the overall fabrication of the partition with pre-reserved break points greatly reduces the workload of drawing, hoisting, transportation, picking parts, and positioning assembly. Pre-processing the butt joint bevel can completely avoid the quality problem of reverse bevel that may occur when beveling separately after cutting later.

[0012] Furthermore, in step S2, each cross section of the tire frame support plate has a lateral slope of at least 2%.

[0013] Furthermore, the specific content of step S3 is as follows: S301: Loosen the connection between the beam and the frame, initially release the stress, separate the blocks along the cutting area of ​​the partition unit, and ensure that each block has a stable support under it before cutting. S302: After correcting local deformation and measuring the overall alignment to meet the specifications, install matching parts at the corresponding locations. The beneficial effects of this step enable the bridge erection to quickly restore the alignment state manufactured in the factory, reducing the difficulty of bridge positioning.

[0014] Furthermore, the specific content of step S302 is as follows: After the block is decoded, it is corrected, and after the dimensions are accepted, the matching parts are installed. Each longitudinal joint of the block is equipped with no less than two sets of matching parts. The top plate matching part of the block is set directly above the partition matching part of the block, and the bottom plate matching part is set 200mm away from the partition. Each transverse joint is equipped with no less than one set of matching parts. The top plate matching part is set directly above the web plate, and the bottom plate matching part is set 200mm away from the web plate. The advantage of this step is that by setting it at or near the structure, it can ensure that the position with the greatest rigidity that is difficult to align manually between the blocks can be quickly and accurately aligned. The other panel positions can be quickly aligned by using a support plate. The determination of the 200mm distance is based on both structural rigidity and construction operability.

[0015] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: 1. The manufacturing method disclosed in this application starts from the early division of manufacturing units, taking into account factors such as avoiding wheel track lines, meeting the lifting capacity of complex sites and the rolling capacity of steel mills, and reducing welds in the support area, to make reasonable division of manufacturing units.

[0016] 2. This application addresses the horizontal and vertical curve alignment control of the entire bridge by adopting a route that involves fabricating the entire span and then disassembling the entire segment. The longitudinal baseline of the top plate in the middle of each segment is connected end to end, and the placement angle is controlled by a main longitudinal baseline that runs through the bridge to determine the overall horizontal alignment. At the same time, the frame and the web plate are used as inner tubes for dual control to ensure the vertical alignment.

[0017] 3. This application employs integrated diaphragm manufacturing technology, cross-slope assembly technology, and small block pre-assembly technology to ensure the compatibility between the joints of the small blocks.

[0018] 4. The manufacturing method of this application meets the manufacturing and precision control requirements of small-radius horizontal curved steel box girders, saves the time occupied by lifting equipment during the manufacturing process, speeds up the production efficiency, is technologically advanced and reliable, saves costs, and has significant economic and social benefits. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic flowchart illustrating a method for manufacturing blocks for a small-radius horizontal curve steel box girder ramp bridge according to a specific embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the segmentation of blocks in a method for manufacturing blocks for a small-radius horizontal curve steel box girder ramp bridge according to a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the alignment positioning control in step S203 of a method for manufacturing blocks for a small-radius horizontal curve steel box girder ramp bridge according to a specific embodiment of the present invention. Figure 4 This is a schematic diagram of the top plate matching component in step S302 of the manufacturing method of a small-radius horizontal curve steel box girder ramp bridge according to a specific embodiment of the present invention; The attached figures are labeled as follows: 1-Longitudinal baseline of the block base plate unit; 2-Partition plate position line; 3-Frame beam; 4-Matching parts; 5-Butt joint Detailed Implementation The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention. It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0021] In the description of this application, it should be understood that the terms "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0022] In this application, unless otherwise expressly specified and limited, the terms "installation," "setup," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] To better understand the above technical solutions, the following will provide a detailed description of the technical solutions in conjunction with the accompanying drawings and specific embodiments.

[0024] Example: In the field of bridge engineering, small-radius horizontal curve steel box girder ramp bridges face numerous technical challenges in manufacturing and erection due to their complex alignment and small radius of curvature (typically less than 300m). Traditional steel box girder manufacturing methods mostly employ general processes for straight sections or large-radius curves, which are difficult to adapt to the spatial geometric nonlinear changes brought about by small-radius curves.

[0025] Therefore, this application provides a method for manufacturing blocks for small-radius horizontal curve steel box girder ramp bridges. The main characteristics of these ramp bridges are a horizontal curve radius of less than 300m and the superimposed vertical curve. Their cross-sectional structure is a single-box multi-cell structure with equal height and width. Based on these characteristics, this application adopts a manufacturing process of "parts → plate units → beam segments → decomposition into blocks." To improve the manufacturing precision of the ramp steel box girder blocks, enhance the matching accuracy and construction efficiency during block erection, and ensure the box opening dimensions, this application proposes for the first time a dedicated block-segmentation scheme for ramp steel box girders, a steel box girder alignment precision control process, and a block matching precision control process.

[0026] like Figure 1-4 As shown, the specific steps of this application are as follows: S1: Create a segmentation scheme, divide the steel box girder ramp bridge to be manufactured into units, the specific contents are as follows; S101: Divide longitudinally to form multiple segments, end supports, and middle supports; S102: Divide multiple segments laterally. During the division, divide them into cantilever arms and lateral blocks. The lateral blocks are located between two cantilever arms. S2: The segments are manufactured using a continuous matching process, and the accuracy of horizontal and vertical curves is controlled during the manufacturing process. S3: Disassemble the segment to obtain the desired block.

[0027] Regarding step S1, the modular design refers to the process of pre-planning the breakdown of the entire bridge into several independently manufactureable, transportable, and assembleable units based on the structural characteristics, transportation conditions, and hoisting capabilities of the steel box girder ramp bridge. Reasonable modular division is crucial for ensuring the smooth progress of the project from manufacturing and transportation to bridge site connection. Based on structural characteristics and road transportation limitations, and comprehensively considering factors such as the structural stability of each unit, avoiding wheel tracks, meeting on-site hoisting capabilities, and the steel mill's rolling capacity, a reasonable modular division of manufacturing units is achieved.

[0028] Specifically, in addition to conventional factors, the longitudinal division should also consider the following: a) the narrow space of expansion joints makes construction difficult. b) the positive bending moment at mid-span and the negative bending moment at pier top of the continuous beam; the area with the maximum bending moment should be avoided, i.e., the above-mentioned areas should be avoided. Regarding the transverse division, for a single-box four-cell structure, it is divided into 7 sections, with 1 section on each side cantilever. Each remaining section should have at least one web plate unit to ensure the structural stability of the divided sections and meet transportation and hoisting requirements. The width of each plate unit should not exceed 4m, and the total width of the section should not exceed 5.3m. For the end and middle support areas, to avoid the impact of dense butt welds on structural safety and the limited construction space at the end expansion joints, the support area is divided into a single transverse section, generally about 4 meters in length, to meet transportation and steel mill rolling capacity. This avoids dense welds in the main stress areas, ensuring structural safety, and also avoids the situation of constructing end support welds in the narrow space of the expansion joint area.

[0029] After designing the segmented scheme, this application first proceeds to the manufacturing stage. After manufacturing is completed, the components are disassembled to obtain the required blocks, which are then transported to the site for assembly and welding to obtain the bridge body.

[0030] The specific content of step S2 is as follows: S201: Define the longitudinal and transverse baselines of the top and bottom plate units in each segment. The longitudinal baselines between segments should be connected end to end. Among them, the longitudinal baselines of each top and bottom plate unit in each segment should be as close as possible to the center line of the plate width and be parallel to each other. The longitudinal baselines between segments should be connected end to end. The transverse baselines in a single segment should form a straight line and be perpendicular to the longitudinal baseline of the segment. S202: The solid bridge line type assembly process is adopted, and the jig is used as the outer jig. In the specific layout, the jig support plates are arranged according to the plane curve direction. The longitudinal direction is based on the principle of the diaphragm unit close to the segment, and the transverse direction is based on the principle of supporting the web unit of the segment and both sides of the joint between two segments. The value is taken at each web of the segment according to the line type after superimposed pre-arching. The values ​​of other positions can be taken by interpolation. S203: The longitudinal baseline extension of the intermediate block bottom plate unit of the segment located in the middle of the steel box girder ramp bridge is used as the longitudinal baseline of the whole bridge. The dimensional relationship between segments and the vertical curve direction of the whole bridge are controlled by controlling the dimensions between the transverse baselines of the intermediate block bottom plate units of each segment and the distance between the transverse baseline, the diaphragm position line and the crossbeam of the formwork. S204: Using the middle block base plate unit of the segment as a reference, position and assemble the remaining base plate units within the segment; to avoid weld shrinkage causing negative beam width difference, the transverse spacing between adjacent base plate units in step S204 is the design value + 2mm. This step also includes the following: verifying the transverse baseline spacing between the outermost segments to ensure that the overall horizontal curve accuracy is controllable. After the measurement is correct, fix the base plate unit to the jig, and at the same time, secure the longitudinal seam of the base plate unit without welding. S205: Position and assemble the first partition unit. The web unit is made according to the curve and used as the inner tube to ensure that the bottom plate unit is in close contact with the frame. The cantilever block shape is based on the box body shape. Temporary connections are set at the joints to control its shape. Ground supports are set on the outside to ensure its stability. Finally, assemble the remaining partition and web units in sequence. S206: Vertical joint between the diaphragm unit and the web unit, and horizontal joint between the diaphragm unit and the bottom plate unit; S207: Using the top plate unit of the middle block of the segment as a reference, locate and assemble the remaining top plate units within the segment; S208: Transverse joint between the welded partition unit and the top plate unit, and longitudinal joint between the top plate unit and the web unit; S209: Repeat steps S204-S208 until all segments are completed.

[0031] Further explanation of step S205: When cutting the partition unit, a 4mm-6mm wide slit is cut along the dividing line, and the butt joint bevel is pre-processed, with a total cutting area of ​​at least 260mm from top to bottom, to ensure the rigidity and integrity of the partition during transportation and assembly. At the same time, in order to adapt to the bottom plate spacing design value +2mm in S204 above, for partitions with cutting areas, the cutting line should be used as the reference, and the process allowance should be +1mm on both the left and right sides of the partition width direction.

[0032] Specifically, in step S2 of this application, each cross section of the frame support plate has a lateral slope of at least 2%; wherein steps S204-S208 are the manufacturing steps for each segment, and steps S204-S208 are repeated until the processing of all segments is completed.

[0033] Further explanation of step S2: Compared to existing processing methods, this application no longer uses a single longitudinal baseline running through the entire bridge. The transverse baselines between beam segments are not required to be parallel. Instead, the longitudinal baselines within each segment composed of blocks are ensured to be parallel, and the transverse baselines are ensured to be perpendicular to them. The longitudinal baselines between each block are kept connected end to end. At the same time, this application selects the middle block of the beam as the positioning reference and performs continuous matching manufacturing. Its longitudinal baseline is extended to the entire bridge to locate the transverse offset of the middle block of the remaining beam segments. Then, the longitudinal dimension is roughly located by the relationship between the crossbeam of the jig and the position line of the diaphragm, and the longitudinal dimension is precisely located by the spacing of the transverse baselines, thus completing the control of the entire planar alignment. The selection of jig support points should focus on key positions. Transverse supports should be arranged at the web position and on both sides of the joint. Other positions can be densely arranged using the tensioning method. The longitudinal supports are arranged near the diaphragm to prevent beam deformation. The top and bottom plate units and the web unit are manufactured according to planar units. The bottom plate is shaped using the jig and the web, the top plate is shaped using the web and the top surface counterweight, and the web unit is shaped using the diaphragm support to achieve a curved surface effect.

[0034] The aforementioned segments are then decomposed to obtain the required blocks. Compared to conventional steel box girders, this bridge type has a significantly increased number of on-site longitudinal butt joints and diaphragm butt joints. To avoid compatibility issues with these numerous longitudinal butt joints, this process, based on the idea of ​​disassembling the entire segment after fabrication, uses diaphragm units for control. An integrated diaphragm fabrication process is adopted, where two butt diaphragms are pre-cut at break points during material preparation, retaining a total length of 260mm without cutting. This maintains the strength of the integrated fabrication, reduces the number of diaphragm units, and eliminates the risk of errors in the butt joint bevel processing. During final assembly, the integrated diaphragm flattens the top and bottom plates on both sides of the butt joint, acting as a support and ensuring the compatibility of the longitudinal butt joints of the top and bottom plate units. Furthermore, the diaphragm itself is disconnected at the connection point after final assembly, improving the overall fabrication accuracy of the steel box girder blocks.

[0035] Specifically, the content of step S3 is as follows: S301: Loosen the connection between the beam and the frame, initially release the stress, separate the blocks along the cutting area of ​​the partition unit, and ensure that each block has a stable support under it before cutting. S302: After correcting local deformation and measuring the overall alignment to meet the specifications, install matching parts in the corresponding positions.

[0036] Specifically, regarding step S302, after the block is decoded, it is corrected, and after the dimensions are accepted, the matching parts are installed. Each longitudinal seam of the block is provided with no less than two sets of matching parts. The top plate matching part of the block is located directly above the partition matching part of the block, and the bottom plate matching part is located 200mm away from the partition. Each transverse seam is provided with no less than one set of matching parts. The top surface is located directly above the web plate, and the bottom plate matching part is located 200mm away from the web plate.

[0037] This step mainly involves using whole-segment fabrication to increase compatibility, while still fabricating the partitions on both sides of the segment as a single piece, leaving breakpoints to facilitate subsequent cutting; for curved steel box girders with equal height and width, continuous matching fabrication is carried out on the transverse slope basis; the pre-assembly of small blocks should be carried out after all hard connections between blocks are removed, including the breakpoints of the integrally fabricated partitions, and after the dimensions of each block are adjusted to meet the requirements, matching components are installed at or near the positions where the block structure has greater rigidity and can drive the blocks to return to a matching state.

[0038] Regarding the matching degree of the transverse circumferential joints, the key consideration is the impact of the cross slope. The bridge's transverse slope is 2%, achieved by rotating the beams along their axes. For small-radius horizontal curve bridges, the bridge axis is not straight, and each beam segment has a fan-shaped plane. Therefore, rotating the beam segments along their respective axes to meet the cross slope requirements inevitably leads to changes in the circumferential joint gap. If the cross slope is not considered during continuous matching fabrication, and continuous matching is performed without a cross slope, the matching degree during bridge erection will not be able to achieve the same level as the pre-assembly in the factory. The smaller the bridge radius and the greater the cross slope, the greater the impact on the matching degree. Therefore, a 2% transverse slope should be considered when selecting the values ​​for each cross section of the formwork support plate to realize the actual working conditions of the beam segments during bridge erection and achieve the optimal matching degree. For the pre-assembly of small blocks, unlike the pre-assembly of conventional box girders, in addition to being carried out after the entire bridge is decoded, all diaphragm connections must be disconnected to release all stress. At the same time, corresponding corrections should be made. After all dimensions have passed inspection, the matching parts should be installed. Each longitudinal joint should have no less than two sets of matching parts, with the top set directly above the diaphragm and the bottom set 200mm away from the diaphragm. Each transverse joint should have no less than one set of matching parts, with the top set directly above the web and the bottom set 200mm away from the web.

[0039] Numerous specific details are set forth in this specification. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification. In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for manufacturing blocks for small-radius horizontal curved steel box girder ramp bridges, characterized in that, Includes the following steps: S1: Create a segmentation scheme, divide the steel box girder ramp bridge to be manufactured into units, the specific contents are as follows; S101: Divide longitudinally to form multiple segments, end supports, and middle supports; S102: Divide multiple segments laterally. During the division, divide them into cantilever arms and lateral blocks. The lateral blocks are located between two cantilever arms. S2: The segments are manufactured using a continuous matching process, and the accuracy of horizontal and vertical curves is controlled during the manufacturing process. S3: Disassemble the segment to obtain the desired block.

2. The manufacturing method according to claim 1, characterized in that, When performing longitudinal division in step S101, the positive bending moment region at the mid-span of the continuous beam and the negative bending moment region at the top of the pier are avoided. The total width of the horizontal blocks in step S102 does not exceed 5.3m.

3. The manufacturing method according to claim 1, characterized in that, The specific content of step S2 is as follows: S201: Define the longitudinal and transverse baselines of the top and bottom plate units in each segment, and the longitudinal baselines between segments should be connected end to end; S202: Adopts solid bridge line assembly process, using the tire frame as the outer tire; S203: The longitudinal baseline extension of the intermediate block bottom plate unit of the segment located in the middle of the steel box girder ramp bridge is used as the longitudinal baseline of the whole bridge. The dimensional relationship between segments and the vertical curve direction of the whole bridge are controlled by controlling the dimensions between the transverse baselines of the intermediate block bottom plate units of each segment and the distance between the transverse baseline, the diaphragm position line and the crossbeam of the formwork. S204: Using the middle block base plate unit of the segment as a reference, locate and assemble the remaining base plate units within the segment; S205: Position and assemble the first partition unit. The web unit is made according to the curve and used as the inner tube to ensure that the bottom plate unit is in close contact with the frame. The cantilever block shape is based on the box body shape. Temporary connections are set at the joints to control its shape. Ground supports are set on the outside to ensure its stability. Finally, assemble the remaining partition and web units in sequence. S206: Vertical joint between the diaphragm unit and the web unit, and horizontal joint between the diaphragm unit and the bottom plate unit; S207: Using the top plate unit of the middle block of the segment as a reference, locate and assemble the remaining top plate units within the segment; S208: Transverse joint between the welded partition unit and the top plate unit, and longitudinal joint between the top plate unit and the web unit; S209: Repeat steps S204-S208 until all segments are completed.

4. The manufacturing method according to claim 3, characterized in that, In step S201, the transverse baseline within each segment forms a straight line, which is perpendicular to the longitudinal baseline of the segment. The longitudinal baselines of the top and bottom plate units within each segment are parallel to each other.

5. The manufacturing method according to claim 3, characterized in that, When arranging the frame in step S202, the frame support plates are arranged in the following manner: the longitudinal direction is based on the partition unit close to the segment, and the transverse direction is based on the position of the web unit of the segment and both sides of the joint between two segments. The values ​​are taken at each web of the segment according to the line shape after superimposed pre-arching, and the values ​​at other positions can be taken by interpolation.

6. The manufacturing method according to claim 3, characterized in that, In step S204, the lateral spacing between adjacent base plate units is the design value + 2mm. This step also includes the following: verifying the lateral baseline spacing between the outermost segments to ensure that the overall horizontal curve accuracy is controllable. After the measurement is correct, the base plate unit is fixed to the jig, and the longitudinal seam of the base plate unit is secured without welding.

7. The manufacturing method according to claim 3, characterized in that, In step S205, when the partition unit is cut, a 4mm-6mm wide slit is cut along the dividing line, and the butt joint bevel is pre-processed, with a total cutting area of ​​at least 260mm to ensure the rigidity and integrity of the partition during transportation and assembly. The partition in the cutting area has a 1mm process allowance on each side of the width direction of the partition unit, based on the cutting line.

8. The manufacturing method according to claim 1, characterized in that, In step S2, each cross section of the frame support plate has a lateral slope of at least 2%.

9. The manufacturing method according to claim 1, characterized in that, The specific content of step S3 is as follows: S301: Loosen the connection between the beam and the frame, initially release the stress, separate the blocks along the cutting area of ​​the partition unit, and ensure that each block has a stable support under it before cutting. S302: After correcting local deformation and measuring the overall alignment to meet the specifications, install matching parts in the corresponding positions.

10. The manufacturing method according to claim 9, characterized in that, The specific content of step S302 is as follows: After the block is decoded, it is corrected and the dimensions are accepted before the matching parts are installed. Each longitudinal seam of the block is provided with no less than two sets of matching parts. The top plate matching part of the block is located directly above the partition matching part of the block, and the bottom plate matching part is located 200mm away from the partition. Each transverse seam is provided with no less than one set of matching parts. The top plate matching part is located directly above the web plate, and the bottom plate matching part is located 200mm away from the web plate.

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