Fabricated steel-concrete composite structure bridge, construction method and design method

Abstract

The invention provides a fabricated steel-concrete composite structure bridge. The fabricated steel-concrete composite structure bridge comprises a plurality of standard prefabricated modules; each standard prefabricated module comprises concrete, two H-shaped steel beams, outer side steel plates, high-strength bolts, shear nails and hook steel bars. The H-shaped steel beam is connected with the outer side steel plate through the high-strength bolts, the concrete is poured on the outer side steel plate, and the shear nails are welded to the side, facing the concrete, of the outer side steel plate. The end, connected with the adjacent standard prefabricated modules, of the outer side steel plate is provided with a connecting part, the hook steel bar is arranged in the concrete, and the end, connected with the adjacent standard prefabricated modules, of the hook steel bar is provided with a lap joint part. Each standard prefabricated module further comprises a connecting steel plate used for connecting the outer side steel plates of the adjacent standard prefabricated modules through high-strength bolts and the connecting steel plates to form pouring cavities during field connection. By adopting standard prefabricated modularization and high-strength bolt connection, the integrity and reliability of the combined structure are improved, the site construction time is shortened, and disassembly and repeated utilization are facilitated.

Description

Technical Field

[0001] This application relates to the field of rapid construction of bridge engineering, specifically to a prefabricated steel-concrete composite bridge, its construction method, and its design method. Background Technology

[0002] Steel-reinforced concrete composite bridge beam structures utilize shear connectors between the steel beams and concrete decks to transfer horizontal shear forces, thereby maximizing the overall structural load-bearing capacity. This approach fully leverages the tensile strength of steel and the compressive strength of concrete, while also offering advantages such as lightweight construction and aesthetic appeal. Traditional steel-concrete composite structures require extensive on-site construction, resulting in long concrete curing periods and significant disruptions to traffic, as well as pollution from construction waste and noise. In contrast, prefabricated bridge structural components typically employ standardized design, factory construction and curing, and on-site assembly, significantly shortening the on-site construction period and minimizing traffic disruption. Furthermore, the welding and bolting connections used for steel components are highly suitable for prefabricated structure installation.

[0003] Existing prefabricated steel-concrete bridge structures generally employ either cluster nail slot connections or longitudinal and transverse wet joint connections. Wet joints require exposed bridge deck reinforcement, which is then connected via lap splices or mechanical connections to meet the needs of longitudinal and transverse reinforcement connections. The detailed construction of these joints is complex, impacting the speed of on-site prefabrication. Furthermore, existing prefabricated steel-concrete bridge structures have low reusability rates for precast components, making large-scale, assembly-line production of precast components difficult, thus limiting the economic viability of prefabricated structures. Additionally, rapid bridge dismantling is a current social concern. The weight of long-span bridges places higher demands on the load-bearing capacity of SPMT (Special Purpose Transporter) vehicles. If bridges can be dismantled quickly and easily during dismantling, the load requirements for SPMT vehicles will be significantly reduced, facilitating their widespread application. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the purpose of this application is to provide a prefabricated steel-concrete composite structure bridge.

[0005] A first aspect of this application provides a prefabricated steel-concrete composite structure bridge, comprising: multiple standard prefabricated modules;

[0006] Each of the aforementioned standard prefabricated modules includes: concrete, two H-beams, an outer steel plate, high-strength bolts, shear studs, and bent reinforcing bars;

[0007] The H-shaped steel beam is connected to the outer steel plate by the high-strength bolts, the concrete is poured on the outer steel plate, and the shear studs are welded to the side of the outer steel plate facing the concrete.

[0008] The outer steel plate has a connecting part at one end connected to the adjacent standard precast module, the hook steel bar is set in the concrete, and one end of the hook steel bar has an overlapping part at one end connected to the adjacent standard precast module.

[0009] The standard prefabricated module also includes a connecting steel plate, which is used to connect the outer steel plate of the adjacent standard prefabricated module to the connecting steel plate through the high-strength bolts during on-site connection to form a casting cavity;

[0010] During bridge construction, the lap joints of the hooked steel bars of adjacent standard prefabricated modules overlap each other, and then quick-setting concrete is poured on-site in the casting cavity. After the quick-setting concrete hardens, a reliable connection is formed, thereby forming the bridge structure.

[0011] Optionally, the standard prefabricated module further includes a diaphragm, which is laterally arranged between the two H-beams.

[0012] Optionally, the upper flange of the H-beam is provided with a bolt through hole in the positive bending moment region, and the upper flange of the H-beam is provided with an elongated hole in the negative bending moment region. The length direction of the elongated hole is consistent with the axial direction of the H-beam, and the width of the elongated hole is the same as the diameter of the bolt through hole.

[0013] Optionally, the aspect ratio of the oblong hole is 3:1.

[0014] Optionally, the bent reinforcing bar is disposed within the concrete;

[0015] The lap joint at one end of the hooked steel bar is a hook structure.

[0016] Optionally, the standard prefabricated module also includes a detachable temporary support frame, which is detachably connected to the two H-shaped steel beams to ensure the safety of the standard prefabricated module during transportation and hoisting.

[0017] Optionally, when assembling the plurality of standard prefabricated modules, the distance between the two H-beams in each standard prefabricated module is a preset fixed spacing that matches the bridge span. The distance between the H-beam and the connection end of the outer steel plate can be adjusted during the prefabrication and installation process according to user needs, forming a variable spacing between the H-beams of adjacent standard prefabricated modules, which is used to match the width of the actual bridge when connecting on site.

[0018] A second aspect of this application provides a construction method for a prefabricated steel-concrete composite bridge, comprising:

[0019] Acquire multiple standard prefabricated modules and transport them to the construction site;

[0020] The standard prefabricated modules are hoisted to the designated positions and connected by connecting steel plates and high-strength bolts.

[0021] Quick-setting concrete is poured on-site at the pouring cavity between adjacent standard prefabricated modules;

[0022] The poured quick-setting concrete is cured to the required curing age before the bridge installation is completed.

[0023] Optionally, the connection strength of each of the standard prefabricated modules connected by connecting steel plates and high-strength bolts is not lower than the strength of the outer steel plate itself;

[0024] Among them, the high-strength bolt spacing s of the outer steel plate b With connection steel plate thickness t cp It needs to meet the following requirements:

[0025]

[0026] min[2fx p (s b -d hole ),2f yp s b ]≥max[f us (s b -d hole ),f ys s b ];

[0027] In the formula, n bs The number of rows of high-strength bolts on one side of the connecting steel plate; l cp The smaller of the clear distance between the high-strength bolts on one side of the connecting steel plate or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; f up The ultimate tensile strength of the connecting steel plate material is measured in MPa. cs f is the smaller of the clear distance between the high-strength bolts on one side of the outer steel plate connection or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; us f represents the ultimate tensile strength of the outer steel plate material, in MPa; yp The yield strength of the connecting steel plate material is given in MPa; d hole The diameter of the through hole at the connection point between the connecting steel plate and the outer steel plate is in mm.

[0028] A third aspect of this application provides a design method for prefabricated steel-concrete composite bridges, comprising:

[0029] Obtain the geometric information of the bridge to determine the standard spacing of the H-beams and the number of standard prefabricated modules; the geometric information includes: bridge deck width, bridge span length, distance from the center line of the support to the end of the bridge deck, and bridge skew angle;

[0030] Based on the geometric information of the bridge, the design load of the steel-concrete composite beam is calculated, and the required H-beam section information is determined based on the design load.

[0031] Based on the geometric information of the bridge, the standard spacing of the H-beams, and the number of standard prefabricated modules, the thickness of the outer steel plate in the standard prefabricated module is calculated.

[0032] Based on the standard spacing of the H-beams, determine the required thickness of the bridge deck concrete by referring to the table, and calculate the required dimensions and spacing of the shear studs.

[0033] Calculate the design value of the horizontal shear force required to be transmitted under the condition that the concrete bridge deck and steel beam form a composite structure, and select the required standard size of high-strength bolts and bolt spacing based on the design value of the horizontal shear force;

[0034] Based on the dimensions of the outer steel plate, calculate the required dimensions, cross-sectional thickness, and bolt spacing of the connecting steel plate used to connect adjacent prefabricated modules.

[0035] Based on the standard spacing of the H-shaped steel beams and the thickness of the concrete bridge deck, the reinforcement design of the upper surface of the bridge deck concrete is carried out to select the appropriate hook steel bar type and spacing.

[0036] This application provides a prefabricated steel-concrete composite bridge structure, which adopts a prefabricated modular design technique. Each standard prefabricated module consists of two H-shaped steel beams connected to an outer steel plate by high-strength bolts. Shear studs are welded to the side of the outer steel plate facing the concrete to enhance the shear resistance of the interface. Concrete is poured onto the outer steel plate and contains embedded hooked reinforcing bars. The outer steel plate has a connecting part at the connection end, and the hooked reinforcing bars have lapped parts. During on-site assembly, adjacent connecting parts are connected to the connecting steel plate and high-strength bolts to form a casting cavity. The lapped parts of adjacent hooked reinforcing bars overlap in the cavity, and the cavity is filled by pouring quick-setting concrete. Through factory prefabrication and quick-setting concrete technology, the integrity and reliability of the composite structure are improved, and on-site construction time is reduced.

[0037] Other technical effects resulting from the additional features will be further illustrated in the corresponding embodiments. Attached Figure Description

[0038] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0039] Figure 1 This is a structural schematic diagram of a cross-section of a standard prefabricated module according to an exemplary embodiment;

[0040] Figure 2 This is a structural schematic diagram of the cross-section of a prefabricated H-beam steel-concrete composite bridge structure according to an exemplary embodiment.

[0041] Figure 3 This is a structural schematic diagram of the longitudinal section of a longitudinally unspliced ​​simply supported composite bridge according to an exemplary embodiment;

[0042] Figure 4 This is a structural schematic diagram of the longitudinal section of a longitudinally spliced ​​simply supported composite structure bridge according to an exemplary embodiment;

[0043] Figure 5 This is a structural schematic diagram of the longitudinal section of a continuous composite structure bridge according to an exemplary embodiment;

[0044] Figure 6 This is a top view of the outer steel plate and connecting steel plate according to an exemplary embodiment;

[0045] Figure 7 The following is a detailed view of a steel plate connection according to an exemplary embodiment: connection in the positive bending moment region (left) and connection in the negative bending moment region (right);

[0046] Figure 8 This is a flowchart illustrating a construction method for a prefabricated steel-concrete composite bridge according to an exemplary embodiment.

[0047] Figure 9 This is a flowchart illustrating a design method for a prefabricated steel-concrete composite bridge according to an exemplary embodiment.

[0048] In the diagram: 1. Standard prefabricated module; 2. H-beam; 3. Outer steel plate; 31. Connecting part; 4. High-strength bolt; 5. Shear stud; 6. Connecting steel plate; 7. Hooked reinforcing bar; 71. Lap joint; 8. Concrete; 9. Quick-setting concrete; 10. Bolt through hole; 11. Diaphragm; 12. Temporary support frame; 13. Oblong hole; 14. Casting cavity. Detailed Implementation

[0049] The present application will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all fall within the protection scope of the present application. Parts not described in detail in the following embodiments can be implemented using existing technology.

[0050] In the description of the embodiments of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this application 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. Therefore, they should not be construed as limitations on this application.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0052] In the description of the embodiments in this application, "multiple" means two or more, unless otherwise explicitly specified. In this application, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0053] The terms "comprising" and "having," and any variations thereof, in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or devices.

[0054] In the prior art, existing prefabricated steel-concrete composite bridge structures suffer from complex connection node construction and low reusability of prefabricated components. To address these issues, this application provides a prefabricated steel-concrete composite bridge structure to solve these problems.

[0055] Reference Figure 1 As shown in one embodiment of this application, a prefabricated steel-concrete composite structure bridge includes: multiple standard prefabricated modules 1.

[0056] Each standard precast module 1 includes: concrete 8, two H-beams 2, outer steel plate 3, high-strength bolts 4, shear studs 5, and bent reinforcing bars 7.

[0057] H-shaped steel beam 2 is connected to outer steel plate 3 by high-strength bolts 4. Concrete 8 is poured on outer steel plate 3. Shear nails 5 are welded to the side of outer steel plate 3 facing concrete 8. A connecting part 31 is provided at the end of the outer steel plate 3 connected to the adjacent standard precast module 1. Hooked steel bars 7 are set in concrete 8. One end of hooked steel bars 7 is provided with an overlap part 71 at the end of the connection to the adjacent standard precast module 1.

[0058] The standard prefabricated module 1 also includes a connecting steel plate 6, which is used to connect the outer steel plate 3 of the adjacent standard prefabricated module 1 to the connecting steel plate 6 through high-strength bolts 4 to form a casting cavity 14 during on-site connection.

[0059] During the bridge construction process, the lap joints 71 of the hook steel bars 7 of adjacent standard precast modules 1 overlap each other, and then quick-setting concrete 9 is poured on-site in the casting cavity 14. After the quick-setting concrete 9 hardens, a reliable connection is formed, thus forming the bridge structure.

[0060] Specifically, multiple standard modules are prefabricated in the factory. Each module consists of two H-shaped steel beams 2 connected to an outer steel plate 3 by high-strength bolts 4 to form a steel frame. Shear studs 5 are welded to the side of the outer steel plate 3 facing the concrete 8. The concrete 8 is then poured onto the outside of the steel frame to form a steel-concrete composite structure. During module design, connection parts 31 are reserved at both ends of the outer steel plate 3, and bent hook steel bars 7 are embedded in the concrete 8, with one end extending to the connection part 31 to form an overlap part 71. During on-site installation, the connection parts 31 of adjacent modules abut against each other and are connected to the connecting steel plate 6 by high-strength bolts 4 to form a closed casting cavity 14. At the same time, the overlap parts 71 of the bent hook steel bars 7 of adjacent modules are staggered within the cavity. Finally, quick-setting concrete 9 is poured into the casting cavity 14 to achieve rigid connection and integration between modules, ultimately constructing a complete bridge structure.

[0061] It should be noted that concrete 8 is precast; quick-setting concrete 9 is cast on site.

[0062] In the embodiments described above, a prefabricated modular design technique is employed. Each standard prefabricated module 1 consists of two H-shaped steel beams 2 connected to an outer steel plate 3 by high-strength bolts 4, forming a composite structure with pre-cast concrete 8 above. Shear studs 5 are welded to the side of the outer steel plate 3 facing the concrete 8 to transfer horizontal shear force. During on-site assembly, the outer steel plates 3 of adjacent prefabricated modules are connected to a connecting plate by high-strength bolts 4 to form a casting cavity 14. The lap joints 71 of adjacent hooked reinforcing bars 7 overlap within the cavity. Then, quick-setting concrete 9 is poured on-site to fill the cavity. After the quick-setting concrete 9 hardens, a complete bridge structure is formed. This application can improve the overall integrity and reliability of prefabricated steel-concrete composite structures, reduce on-site construction time, simplify the node construction of prefabricated structure on-site assembly positions, thereby improving on-site construction efficiency, and increase the production efficiency of prefabrication plants. It enables standardized construction and assembly line production of prefabricated components, increases the reusability of prefabricated modules in different projects, and thus significantly reduces the engineering cost of prefabricated structures. Furthermore, the bridge construction method proposed in this application can significantly simplify the bridge installation and dismantling process and facilitate the reuse of dismantled bridge components in other projects.

[0063] In some specific embodiments of this application, the standard prefabricated module 1 also includes a diaphragm 11, which is laterally arranged between two H-shaped steel beams 2.

[0064] In the above embodiments of this application, a stable frame structure of the standard prefabricated module 1 is formed by transversely setting a diaphragm 11 between the two H-shaped steel beams 2 of the standard prefabricated module 1, thereby improving the overall torsional stiffness and lateral stability. At the same time, by constraining the lateral deformation of the steel beams, their local buckling bearing capacity is enhanced.

[0065] In some specific embodiments of this application, a bolt through hole 10 is provided on the upper flange of the H-beam 2 in the positive bending moment region, and an elongated hole 13 is provided on the upper flange of the H-beam 2 in the negative bending moment region. The length direction of the elongated hole 13 is consistent with the axial direction of the H-beam 2, and the width of the elongated hole 13 is the same as the diameter of the bolt through hole 10.

[0066] In the above embodiments of this application, bolts are used to achieve a quick connection between the steel beam and the outer steel plate 3, improving construction efficiency. Standard bolt through holes 10 are drilled in the positive bending moment zone of the upper flange of the H-shaped steel beam 2, and oblong holes 13 are opened in the negative bending moment zone. The length direction of the oblong holes 13 is consistent with the axial direction of the H-shaped steel beam 2, and the width of the oblong holes 13 is equal to the diameter of the standard bolt through holes 10. This achieves the effect of forming a combined structure between the concrete 8 and the H-shaped steel beam 2 in the positive bending moment zone, but not forming a combined structure in the negative bending moment zone, thereby reducing the tensile stress of the concrete 8 in the negative bending moment zone and preventing the concrete 8 from cracking.

[0067] The aspect ratio of the oblong hole 13 is 3:1.

[0068] In some specific embodiments of this application, the hooked reinforcing bar 7 is disposed within the concrete 8, and the lap joint 71 at one end of the hooked reinforcing bar 7 has a hook structure. The hook structure is designed to reduce the required lap length, thereby reducing the width of the splice section and decreasing the amount of concrete 8 poured on-site. The required lap length of the hooked reinforcing bar 7 is much shorter than that of the straight reinforcing bar, thus significantly reducing the width of the pouring cavity 14 and reducing the workload of pouring concrete 8 on-site.

[0069] In some specific embodiments of this application, the standard prefabricated module 1 also includes a temporary support frame 12, which is detachably connected to two H-shaped steel beams to ensure the safety of the standard prefabricated module 1 during transportation and hoisting.

[0070] The temporary support frame 12 was dismantled during construction.

[0071] In some specific embodiments of this application, when assembling multiple standard prefabricated modules 1, the distance between the two H-beams 2 in each standard prefabricated module 1 is a fixed spacing. The distance between adjacent standard prefabricated modules 1 can be adjusted according to user needs to form a variable spacing by adjusting the distance between the connection end of the H-beam 2 and the outer steel plate 3 in the prefabricated module, thereby matching the width of the actual bridge when connecting on site.

[0072] By keeping the distance between the two H-beams 2 in the standard prefabricated module 1 constant, while allowing the distance between adjacent standard prefabricated modules 1 to be variable, the spacing between adjacent prefabricated components can be adjusted to match the bridge width. The positive bending moment zone and the negative bending moment zone of the bridge use corresponding standard prefabricated modules 1, and the details of the longitudinal connection between the modules in the positive bending moment zone and the negative bending moment zone are similar to the details of the transverse connection between the prefabricated modules.

[0073] Through the above embodiments, the number of prefabricated modules required for transverse connection can be flexibly selected, and the bridge width can be matched by adjusting the spacing between adjacent standard prefabricated modules 1. For simply supported bridges with a length exceeding 30 meters, in order to meet the needs of transportation and hoisting, longitudinal segmental connection of standard prefabricated modules 1 along the length of the bridge can be carried out on the basis of transverse connection between standard prefabricated modules 1. It is recommended that the length of the longitudinal segment be taken as the maximum length that meets the transportation and hoisting requirements to reduce the number of connections. The connection of the longitudinal segment should be far away from the high stress area of ​​the bridge.

[0074] Reference Figure 8 As shown, a second aspect of this application provides a construction method for a prefabricated steel-concrete composite bridge, comprising:

[0075] S100: Obtain multiple standard prefabricated modules and transport them to the construction site;

[0076] S200. Hoist the standard prefabricated modules to the designated positions and connect each standard prefabricated module using connecting steel plates and high-strength bolts;

[0077] S300. Quick-setting concrete is poured on-site at the pouring cavity between adjacent standard precast modules.

[0078] S400: Curing of the poured quick-setting concrete to the required curing age is carried out to complete bridge installation.

[0079] Specifically, during bridge construction, multiple standard modules are first prefabricated in the factory and transported to the construction site. Then, using lifting equipment, each module is precisely hoisted to its designed position on the bridge. The connection between adjacent modules is mechanically fixed using connecting steel plates and high-strength bolts, forming a stable structural framework and a closed casting cavity. Next, quick-setting concrete is poured into the cavity for fixation, utilizing its rapid setting characteristics to shorten the on-site waiting time. Finally, the cast-in-place structure is covered and moisturized according to specifications. After the concrete reaches the design strength age, the installation and connection of the overall bridge structure are completed, achieving efficient and high-quality prefabricated construction.

[0080] In some specific embodiments of this application, the connection strength of each standard prefabricated module connected by connecting steel plates and high-strength bolts is not lower than the strength of the outer steel plate itself.

[0081] Among them, the spacing s of the high-strength bolts connecting the outer steel plate b With connection steel plate thickness t cp It needs to meet the following requirements:

[0082]

[0083] min[2f up (s b -d hole ),2f yp s b ]≥max|f us (s b -d hole )f ys s b ];

[0084] In the formula, n bs In this example, n represents the number of rows of high-strength bolts on one side of the connecting steel plate. bs =1, which can be increased according to the actual situation; l cp The smaller of the clear distance between the high-strength bolts on one side of the connecting steel plate or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; f up The ultimate tensile strength of the connecting steel plate material is measured in MPa. cs f is the smaller of the clear distance between the high-strength bolts on one side of the outer steel plate connection or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; us f represents the ultimate tensile strength of the outer steel plate material, in MPa;yp The yield strength of the connecting steel plate material is given in MPa; d hole The diameter of the through hole at the connection point between the connecting steel plate and the outer steel plate is in mm.

[0085] Reference Figure 9 As shown, a third aspect of this application provides a design method for a prefabricated steel-concrete composite bridge, comprising:

[0086] S1. Obtain the geometric information of the bridge to determine the standard spacing of the H-beams and the number of standard prefabricated modules; the geometric information includes: bridge deck width, bridge span length, distance from the center line of the support to the end of the bridge deck, and bridge skew angle;

[0087] S2. Based on the geometric information of the bridge, calculate the design load of the steel-concrete composite beam, and determine the required H-beam section information based on the design load;

[0088] S3. Based on the bridge's geometric information and the standard spacing of the H-beams and the number of standard prefabricated modules, calculate the thickness of the outer steel plate in the standard prefabricated module.

[0089] S4. Based on the standard spacing of H-beams, refer to the table to determine the required thickness of the bridge deck concrete, and calculate the required dimensions and spacing of shear studs.

[0090] S5. Calculate the design value of the horizontal shear force required to be transmitted under the condition that the concrete bridge deck and steel beam form a composite structure. Select the required standard size of high-strength bolts and bolt spacing based on the design value of the horizontal shear force.

[0091] S6. Based on the dimensions of the outer steel plate, calculate the required dimensions, cross-sectional thickness, and bolt spacing of the connecting steel plate used to connect adjacent prefabricated modules.

[0092] S7. Based on the standard spacing of the H-beams and the thickness of the concrete bridge deck, design the reinforcement of the upper surface of the concrete bridge deck to select the appropriate hook steel bar type and spacing.

[0093] Specifically, during the design phase, the following steps are taken: First, obtain the bridge's geometric dimensions, including the bridge deck width, span length, distance from the support centerline to the bridge deck end, and the bridge's skew angle. Based on the bridge deck width, determine the standard spacing of the required H-beams within that width range and the number of prefabricated modules required. The spacing between adjacent prefabricated modules is calculated by subtracting the standard spacing of the H-beams within the prefabricated module unit from the bridge deck width. Using common engineering software, calculate the design load of the steel-concrete composite beam and, based on the design load, calculate the required H-beam cross-sections. Then, based on the distance from the support centerline to the bridge deck end, the width of the cantilever end of the bridge deck, the spacing between adjacent prefabricated modules calculated in step S2, and the standard spacing of the H-beams, calculate the prefabricated module... The length, width, and required thickness of the outer steel plate in the block are determined. Based on the spacing of the H-beams, the required thickness of the bridge deck concrete is determined by referring to a table. The required shear stud size and spacing are calculated by calculating the full-section tensile force of the H-beams and the full-section compressive force of the concrete. The required horizontal shear force is calculated to meet the condition of forming a composite structure between the concrete bridge deck and the steel beams. Based on the calculated horizontal shear force, the required standard size of high-strength bolts and the bolt spacing are selected. Based on the outer steel plate thickness calculated in step S4, the required connecting steel plate size, cross-sectional thickness, and bolt spacing for connecting the outer steel plates of adjacent precast modules are calculated. Based on the H-beam spacing and the concrete bridge deck thickness, the reinforcement design of the upper surface of the bridge deck concrete is carried out, and appropriate rebar size and spacing are selected.

[0094] The embodiments described above in this application determine the standard spacing of H-beams and the number of standard prefabricated modules by obtaining precise geometric information of the bridge. Simultaneously, the design load of the steel-concrete composite beam is calculated, and the cross-section of the H-beams is determined to ensure sufficient strength and stability of the bridge under various loads. The dimensions of the outer steel plates in the standard prefabricated modules, the thickness of the bridge deck concrete, and the dimensions and spacing of shear studs are calculated to optimize the performance of each component, improve the overall structural integrity and durability, and select the dimensions and spacing of high-strength bolts and related parameters for connecting steel plates to ensure reliable connections between the prefabricated modules. Finally, the reinforcement design of the upper surface of the bridge deck concrete is carried out, making the bridge safer, more economical, and more efficient in design, construction, and use.

[0095] In the design process of standard prefabricated modules, the number N1 of shear studs welded to the outer steel plate of the standard prefabricated module is calculated according to Formula 1:

[0096]

[0097] In the formula: C cp The pressure across the entire cross-section of the precast concrete module is calculated according to Formula 2; T s The tensile force across the entire cross-section of the H-beam in the precast module is calculated according to Formula 3; Q r The shear strength of a single shear stud is calculated according to Formula 4.

[0098] Precast modular concrete full-section pressure C cp (Unit: N) Calculation is shown in Formula 2:

[0099] C cp =0.85f c ′ bt s Formula 2

[0100] In the formula: f c ’ b is the 28-day compressive strength of concrete, in MPa; b is the width of the concrete in the precast module, in mm; t s The thickness of the bridge deck concrete is in mm.

[0101] Full-section tensile force T of H-beams in prefabricated modules s (Unit: N) Calculation is shown in Formula 3:

[0102] T s =nf y A s Formula 3

[0103] In the formula: f y is the material yield strength of the H-beam, in MPa; n is the number of H-beams in the prefabricated module, in this example n = 2; A s The cross-sectional area of ​​a single H-beam is expressed in mm². 2 .

[0104] Single shear nail strength Q r (Unit: N) Calculation is shown in Formula 4:

[0105]

[0106] Where: φ sc The material reduction factor for shear studs is recommended to be 0.85; A sc The cross-sectional area of ​​the shear stud is in mm². 2 E c f is the elastic modulus of concrete, in MPa; uc denoted as the ultimate tensile strength of the shear stud material, in MPa.

[0107] In this application, the spacing p of the high-strength bolts connecting the H-beam and the outer steel plate should be the smaller value calculated under the conditions of both the section strength design requirements and the bolt fatigue resistance design criteria, as shown in Formula 5:

[0108] p = min(p str ,p fat ) Formula 5

[0109] In the formula: pstr Bolt spacing (mm) is required to meet the cross-sectional strength design requirements; p fat The bolt spacing, in mm, is specified to meet the bolt fatigue resistance design criteria.

[0110] Among them, the bolt spacing p that meets the cross-sectional strength design requirements str The result is obtained through calculation using Formula 6:

[0111]

[0112] In the formula: φ is the material reduction factor for high-strength bolts, and a value of 0.75 is recommended; R n The value is the smaller of the nominal shear capacity of the high-strength bolt and the bearing capacity of the through-hole support at the connection surface, calculated as shown in Formula 7; n b In this example, n represents the number of rows of bolts connecting the H-beam to the outer steel plate. b =2; d v V represents the distance between the centroid of the compressive force on the concrete and the centroid of the tensile force on the H-beam under external loads. If no more precise method is used for calculation, it can be approximated as the distance between the centroid of the H-beam section and the centroid of the bridge deck concrete, in mm. u —The shear force value (N) at the design section under the strength design criteria.

[0113] In Formula 6, R n (Unit: N) Calculated using Formula 7:

[0114] R n =min(0.6f) yb A b 1.2l c tf u ) Formula 7

[0115] In the formula: f yb A represents the yield strength of the bolt material, in MPa; b The cross-sectional area of ​​the bolt is in mm. 2 ;l c The bolt clearance is calculated by subtracting the diameter of the through hole from the center distance of the bolts, in mm; t is the thickness of the connecting surface, taken as the smaller value between the thickness of the upper flange of the H-beam and the thickness of the outer steel plate, in mm; f u The ultimate tensile strength of the H-beam or outer steel plate material, in MPa;

[0116] In this application, the bolt spacing p needs to meet the bolt fatigue resistance design criteria. fat Determined by Formula 8:

[0117]

[0118] In the formula: Z rThe fatigue strength of the bolt, in nanometers (N), is calculated from the relevant specifications and will not be detailed here; I c The moment of inertia of the combined section of the H-beams and the concrete bridge deck within the effective width, in mm. 4 V fat.u The range of vertical shear force variation at the design section under vehicle live load, N; Q c The static moment of the combined section formed by the H-beam and the concrete bridge deck within the effective width at the connection point between the steel beam and the outer steel plate, in mm. 3 .

[0119] Among them, the outer steel plate and the connecting steel plate are as follows Figure 6 As shown, the structural details of the connection between the outer steel plates via connecting steel plates are as follows: Figure 7 As shown, the thickness t of the outer steel plate ss (Unit: mm) The design requirements for the positive bending moment of the steel-concrete bridge deck between H-beams should be met. ss It can be determined by solving formula 9.

[0120]

[0121]

[0122] In the formula: φ is the flexural reduction coefficient of the steel-concrete composite material, and a value of 0.9 is recommended; M nd + M represents the positive bending moment bearing capacity per unit length of the bridge deck section parallel to the H-beam direction, in Nm / m; ud + f is the positive bending moment of the bridge deck subjected to external loads parallel to the H-beams, in Nm / m; ys f is the tensile yield strength of the outer steel plate, in MPa; c ’ The value represents the 28-day compressive strength of concrete, in MPa.

[0123] Reference Figure 2 Adjacent prefabricated modules are connected by connecting steel plates and high-strength bolts, and the connection strength should not be lower than the strength of the outer steel plate itself. The spacing sb (unit: mm) of the high-strength bolts used to connect the outer steel plate and the thickness tcp (unit: mm) of the connecting steel plate must meet the requirements of Formula 10:

[0124]

[0125] min[2f up (s b -d hole ),2f yp s b ]≥max[f us (sb -d hole ),f ys s b ];

[0126] Where: n bs To represent the number of rows of high-strength bolts on one side of the connecting steel plate, in this example, n... bs =1;l cp The smaller of the clear distance between the high-strength bolts on one side of the connecting steel plate or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; f up The ultimate tensile strength of the connecting steel plate material is measured in MPa. cs f is the smaller of the clear distance between the high-strength bolts on one side of the outer steel plate connection or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; us f represents the ultimate tensile strength of the outer steel plate material, in MPa; yp The yield strength of the connecting steel plate material is given in MPa; d hole The diameter of the through hole at the connection point between the connecting steel plate and the outer steel plate, in mm;

[0127] In formula 10, the parameter f yb A b The meaning is the same as described in Formula 7; t ss f ys The meaning is the same as that described in Formula 9.

[0128] Reference Figure 2 As shown, the reinforcement of the concrete bridge deck must meet the design requirements for negative bending moment of the concrete bridge deck between the H-beams, as shown in Formula 11:

[0129]

[0130] In the formula: φ is the bending reduction coefficient of the steel plate concrete material, which is consistent with the value in Formula 9; M - nd The negative bending moment bearing capacity per unit length of the bridge deck section parallel to the H-beam direction, in Nm / m; M - ud f is the negative bending moment per unit length of the bridge deck subjected to external loads parallel to the H-beams, expressed in Nm / m. yb A represents the tensile yield strength of the reinforcing steel, in MPa; s The area of ​​reinforcing steel bars per unit length parallel to the direction of the H-beam, in mm. 2 / mm;d s ’ f is the distance from the bottom of the concrete bridge deck to the centroid of the welded wire mesh, in mm; c ’ The 28-day compressive strength of concrete, in MPa;

[0131] The following examples and comparative examples will be used to further illustrate this application in order to better understand the above-mentioned technical solutions. It should be understood that the following are only some examples and are not intended to limit this application.

[0132] In the application examples of this application, for prefabricated H-beam-steel plate concrete composite simply supported bridges with a length of less than 30 meters, after the prefabricated modules are transported to the site and hoisted to the designated positions on the abutments, they are then constructed using methods such as... Figure 2 The connection structure shown connects the prefabricated modules horizontally, and finally follows the... Figure 2 Quick-setting concrete was poured at the indicated location and cured to the specified age. Guardrails were then installed. The completed H-beam steel-concrete composite structure simply supported bridge is shown below. Figure 3 As shown.

[0133] For simply supported bridges with prefabricated H-beam-steel plate concrete composite structures exceeding 30 meters in length, it is recommended to use multiple prefabricated modules for longitudinal connection to form a unified bridge structure. After the prefabricated modules are transported to the site and hoisted to the designated positions on the abutments, they are first subjected to... Figure 4 The connection shown is a longitudinal connection between modules, and quick-setting concrete is poured at the connection point, then... Figure 2 The connection structure shown connects precast modules laterally, and quick-setting concrete is poured at the connection points. Finally, guardrails are installed. The completed H-beam steel-concrete composite structure simply supported bridge is as follows: Figure 4 As shown.

[0134] For prefabricated H-beam-steel plate concrete composite continuous bridges, the installation process is similar to that of simply supported bridges over 30 meters in length. Firstly, it involves... Figure 5 The connection shown represents a longitudinal connection between prefabricated modules in the negative bending moment zone and the positive bending moment zone, with quick-setting concrete poured at the connection point. Here, 0.2L-0.3L represents the approximate range of the negative bending moment zone under the bridge's own dead load, and the splicing location should be chosen where the bending moment is close to zero. Then, through methods such as... Figure 2 The connection structure shown connects precast modules laterally, and quick-setting concrete is poured at the connection points. Finally, guardrails are installed. The completed H-beam steel-concrete composite structure simply supported bridge is as follows: Figure 5 As shown.

[0135] The foregoing has described some specific embodiments of this application. It should be understood that this application is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the substantive content of this application. The above-described preferred features can be used in any combination without conflict.

Claims

1. A prefabricated steel-concrete composite structure bridge, characterized in that, include: Multiple standard prefabricated modules; Each of the aforementioned standard prefabricated modules includes: concrete, two H-beams, an outer steel plate, high-strength bolts, shear studs, and bent reinforcing bars; The H-shaped steel beam is connected to the outer steel plate by the high-strength bolts, the concrete is poured on the outer steel plate, and the shear studs are welded to the side of the outer steel plate facing the concrete. The outer steel plate has a connecting part at one end connected to the adjacent standard precast module, the hook steel bar is set in the concrete, and one end of the hook steel bar has an overlapping part at one end connected to the adjacent standard precast module. The standard prefabricated module also includes a connecting steel plate, which is used to connect the outer steel plate of the adjacent standard prefabricated module to the connecting steel plate through the high-strength bolts during on-site connection to form a casting cavity; During bridge construction, the lap joints of the hooked steel bars of adjacent standard prefabricated modules overlap each other, and then quick-setting concrete is poured on-site in the casting cavity. After the quick-setting concrete hardens, a reliable connection is formed, thereby forming the bridge structure.

2. The prefabricated steel-concrete composite structure bridge according to claim 1, characterized in that, The standard prefabricated module also includes a diaphragm, which is arranged laterally between the two H-beams.

3. A prefabricated steel-concrete composite structure bridge according to claim 1, characterized in that, The upper flange of the H-beam has a bolt through hole in the positive bending moment region and an oblong hole in the negative bending moment region. The length direction of the oblong hole is consistent with the axial direction of the H-beam, and the width of the oblong hole is the same as the diameter of the bolt through hole.

4. A prefabricated steel-concrete composite structure bridge according to claim 3, characterized in that, The aspect ratio of the oblong hole is 3:

1.

5. A prefabricated steel-concrete composite structure bridge according to claim 1, characterized in that, The bent steel bar is set inside the concrete; The lap joint at one end of the hooked steel bar is a hook structure.

6. A prefabricated steel-concrete composite structure bridge according to claim 1, characterized in that, The standard prefabricated module also includes a detachable temporary support frame, which is detachably connected to the two H-shaped steel beams to ensure the safety of the standard prefabricated module during transportation and hoisting.

7. A prefabricated steel-concrete composite structure bridge according to claim 1, characterized in that, When the multiple standard prefabricated modules are assembled, the distance between the two H-beams in each standard prefabricated module is a preset fixed spacing that matches the bridge span. The distance between the H-beam and the connection end of the outer steel plate can be adjusted during the prefabrication and installation process according to user needs, forming a variable spacing between the H-beams of adjacent standard prefabricated modules, which is used to match the width of the actual bridge when connecting on site.

8. A construction method for a prefabricated steel-concrete composite bridge according to any one of claims 1-7, characterized in that, include: Obtain the standard prefabricated modules required for the project and transport them to the construction site; The standard prefabricated modules are hoisted to designated positions, and each standard prefabricated module is connected by connecting steel plates and high-strength bolts to form a casting cavity; Quick-setting concrete is poured on-site at the pouring cavity location between adjacent standard prefabricated modules; The poured quick-setting concrete is cured to the required curing age before the bridge installation is completed.

9. The construction method according to claim 8, characterized in that, When connecting the standard prefabricated modules by connecting steel plates and high-strength bolts, the connection strength shall not be lower than the strength of the outer steel plate itself. Among them, the high-strength bolt spacing s of the outer steel plate b With connection steel plate thickness t cp It needs to meet the following requirements: min[2f up (s b -d hole ),2f yp s b ]≥max[f us (s b -d hole ),f ys s b ]; In the formula, n bs The number of rows of high-strength bolts on one side of the connecting steel plate; l cp The smaller of the clear distance between the high-strength bolts on one side of the connecting steel plate or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; f up The ultimate tensile strength of the connecting steel plate material is measured in MPa. cs f is the smaller of the clear distance between the high-strength bolts on one side of the outer steel plate connection or the clear distance between the high-strength bolts and the edge of the connecting steel plate, in mm; us f represents the ultimate tensile strength of the outer steel plate material, in MPa; yp The yield strength of the connecting steel plate material is given in MPa; d hole The diameter of the through hole at the connection point between the connecting steel plate and the outer steel plate is in mm.

10. A design method for a prefabricated steel-concrete composite bridge according to any one of claims 1-7, characterized in that, include: Obtain the geometric information of the bridge to determine the standard spacing of the H-beams and the number of standard prefabricated modules; The geometric information includes: bridge deck width, bridge span length, distance from the center line of the support to the end of the bridge deck, and bridge skew angle; Based on the geometric information of the bridge, the design load of the steel-concrete composite beam is calculated, and the required H-beam section information is determined based on the design load. Based on the geometric information of the bridge, the standard spacing of the H-beams, and the number of standard prefabricated modules, the thickness of the outer steel plate in the standard prefabricated module is calculated. Based on the standard spacing of the H-beams, determine the required thickness of the bridge deck concrete by referring to the table, and calculate the required dimensions and spacing of the shear studs. Calculate the design value of the horizontal shear force required to be transmitted under the condition that the concrete bridge deck and steel beam form a composite structure, and select the required standard size of high-strength bolts and bolt spacing based on the design value of the horizontal shear force; Based on the dimensions of the outer steel plate, calculate the required dimensions, cross-sectional thickness, and bolt spacing of the connecting steel plate used to connect adjacent prefabricated modules. Based on the standard spacing of the H-shaped steel beams and the thickness of the concrete bridge deck, the reinforcement design of the upper surface of the bridge deck concrete is carried out to select the appropriate hook steel bar type and spacing.

Images