Corrugated steel web prestressed concrete composite beam and construction method thereof

Abstract

The present application relates to the technical field of bridge engineering, and particularly relates to a corrugated steel web prestressed concrete composite beam and a construction method thereof, steps of which comprise: prefabricating an upper flange steel plate, a corrugated steel web and a lower flange steel plate, and arranging a row of through holes at each of the two ends of the lower flange steel plate along the length direction and penetrating along the thickness direction; welding the corrugated steel web and the upper flange steel plate, and welding an open plate shear key on the upper flange steel plate and the lower flange steel plate; arranging a tensioning rope in the through hole, fixing the tensioning rope at one end and connecting the tensioning rope at the other end with a force applying device to tension the lower flange steel plate; maintaining the tensioning state, welding the lower flange steel plate with the corrugated steel web and the upper flange steel plate, and pouring a concrete bottom plate; releasing the tensioning, pouring a concrete top plate; cutting off the end area where the two rows of through holes are located, and the manufacturing is completed. The corrugated steel web prestressed concrete composite beam has the beneficial effects that complex lateral supports arranged on both sides of the corrugated steel web can be saved, and the safety hidden danger caused by the instability of the lateral supports is reduced.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering technology, and in particular to a corrugated steel web prestressed concrete composite beam and its construction method. Background Technology

[0002] Traditional precast beams typically have concrete webs, which are heavy and prone to cracking. Steel-concrete composite beams, on the other hand, offer advantages such as light weight, high load-bearing capacity, low carbon footprint, environmental friendliness, and good economic benefits, making them one of the main development directions for modern bridge structures. Corrugated steel web prestressed concrete composite beams, as an economical, efficient, and easy-to-construct new type of bridge, have gained widespread acceptance among bridge engineers and are gradually being applied to large and medium-sized bridges (spans over 50m). Pre-bent prestressed composite beams, also known as pre-bent beams, are a special type of steel-concrete composite beam structure. They utilize the bending moment released when the pre-bending force is unloaded to apply prestress to the concrete, thereby limiting concrete cracking and improving the beam's load-bearing capacity, exhibiting excellent performance indicators and economic efficiency.

[0003] Pre-bent composite beams are generally composed of steel beams and concrete top and bottom slabs. They are fabricated in a prefabrication plant or on the construction site before being hoisted and positioned. Currently, the application of pre-bent composite beams in small- and medium-span simply supported bridges in my country is not widespread. This is primarily due to several factors. First, traditional pre-bent composite beams consume a large amount of steel, resulting in higher costs than conventional steel-concrete composite beams. Second, steel beams have a large bending moment of inertia, making it difficult to apply pre-bending forces. Third, during the fabrication of pre-bent steel beams, the compression side is prone to instability, requiring lateral supports, which further increases the fabrication costs.

[0004] Therefore, those skilled in the art aim to solve the aforementioned technical problems. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a corrugated steel web prestressed concrete composite beam and its construction method, which solves the technical problems in the prior art that the steel beam is prone to instability in the compression part when loaded, requiring the setting of complex lateral supports, and that the concrete bottom plate or top plate is prone to tensile stress and concrete cracking after the steel beam releases the pre-bending force.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0009] In a first aspect, the present invention provides a construction method for a corrugated steel web prestressed concrete composite beam, comprising the following steps: S1: prefabricating an upper flange steel plate, a corrugated steel web, and a lower flange steel plate; providing a row of through holes at each end of the lower flange steel plate along its length direction; all through holes in each row are spaced apart along the width direction of the lower flange steel plate; each through hole penetrates the lower flange steel plate along its thickness direction; S2: welding the corrugated steel web to the upper flange steel plate; welding perforated shear keys to the surface of the upper flange steel plate away from the corrugated steel web; and welding perforated shear keys to the lower flange steel plate; S3: inserting tension ropes into both rows of through holes; fixing the tension ropes connected to one row of through holes; and connecting the tension ropes connected to the other row of through holes to a force-applying device for even tensioning. S4: While the lower flange steel plate is under tension, weld it to the corrugated steel web and upper flange steel plate that have been welded together to form an I-shaped structure. The perforated plate shear key on the lower flange steel plate is located on the plate surface of the lower flange steel plate away from the corrugated steel web. Then, fix the perforated plate shear key on the lower flange steel plate to the reinforcing bars and pour concrete to form a concrete base slab. The pouring area is the area between the two rows of through holes on the lower flange steel plate. S5: Release the tension on the lower flange steel plate, fix the perforated plate shear key on the upper flange steel plate to the reinforcing bars and pour concrete to form a concrete top slab. S6: Cut off the end area where the two rows of through holes are located on the lower flange steel plate to complete the fabrication of the corrugated steel web prestressed concrete composite beam.

[0010] Optionally, in step S2, the welding of the corrugated steel web and the upper flange steel plate, the welding of the upper flange steel plate and the shear key of the perforated plate, and the welding of the lower flange steel plate and the perforated plate are all done with double-sided fillet welds; in step S4, the welding of the lower flange steel plate and the corrugated steel web and the upper flange steel plate that have been welded together is done with double-sided fillet welds.

[0011] Optionally, both rows of through holes are circular through holes arranged linearly at equal intervals. The distance between two adjacent through holes is less than or equal to the smaller of 7d0 or 16t, and greater than or equal to 3.5d0. The distance between the center line of the through hole and the corresponding end edge of the lower flange steel plate is less than or equal to the smaller of 8t or 120mm, and greater than or equal to 1.5d0. Where t refers to the thickness of the lower flange steel plate and d0 refers to the diameter of the through hole.

[0012] Optionally, the diameter d0 of the through hole satisfies: 10mm≤d0≤30mm.

[0013] Optionally, in step S3, the tension ropes connected to one row of through holes are fixed on the reaction frame, and the free ends of the tension ropes are arranged in a row. The tension ropes connected to each through hole in the other row are connected to a force application device to uniformly tension the lower flange steel plate to the design load.

[0014] Optionally, the perforated plate shear key on the upper flange steel plate is perpendicular to it, and the extension direction of the perforated plate shear key is the same as the length direction of the upper flange steel plate.

[0015] The perforated shear key on the lower flange steel plate is perpendicular to it, and the extension direction of the perforated shear key is the same as the length direction of the lower flange steel plate.

[0016] Optionally, in step S3, the tension ropes connected to a row of through holes are fixed on the reaction frame, the force application device is a jack, and one tension rope is connected to an independent jack.

[0017] Secondly, the present invention provides a corrugated steel web prestressed concrete composite beam, which is manufactured according to the construction method of corrugated steel web prestressed concrete composite beam; the corrugated steel web prestressed concrete composite beam includes a corrugated steel web, an upper flange steel plate, a lower flange steel plate, a concrete top plate, a concrete bottom plate, and perforated plate shear keys; the upper flange steel plate and the lower flange steel plate are parallel and spaced apart, and the corrugated steel web is vertically welded between the two opposite plates of the upper flange steel plate and the lower flange steel plate; the concrete top plate is firmly connected to the upper plate surface of the upper flange steel plate through perforated plate shear keys and reinforcing bars, and the concrete bottom plate is firmly connected to the lower plate surface of the lower flange steel plate through perforated plate shear keys and reinforcing bars.

[0018] (III) Beneficial Effects

[0019] The beneficial effects of this invention are as follows: The construction method of this invention for a corrugated steel web prestressed concrete composite beam involves first prefabricating an upper flange steel plate, a corrugated steel web, and a lower flange steel plate. A row of through holes is provided at each end of the lower flange steel plate along its length. All through holes in each row are spaced apart along their width and penetrate the lower flange steel plate. Tensioning ropes are inserted into the through holes at both ends of the lower flange steel plate and connected to a force-applying device. The lower flange steel plate is then uniformly tensioned to the design load, ensuring that the lower flange steel plate remains stable under tension during the subsequent pouring of the concrete base slab. Compared to the prior art which involves setting complex lateral supports on both sides of the corrugated steel web, this method significantly reduces material and labor costs while also minimizing safety hazards caused by unstable lateral supports. Furthermore, this invention applies tensile stress to the lower flange steel plate by tensioning it. After the concrete base slab is poured, the concrete base slab is subjected to a reaction force from the lower flange steel plate, generating compressive stress within the concrete base slab. This pre-introduced compressive stress can offset some of the tensile stress caused by external loads, thereby reducing the risk of concrete cracking, improving crack resistance, and extending the durability and service life of the concrete structure. Simultaneously, the perforated plate shear keys connect the upper flange steel plate and the concrete top slab, and the lower flange steel plate and the concrete base slab, respectively, forming a stable integral structure and improving structural stability. Attached Figure Description

[0020] Figure 1This is a schematic flowchart of Embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0021] Figure 2 This is a schematic diagram illustrating step S1 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0022] Figure 3 This is a schematic diagram showing the completion of welding between the corrugated steel web and the upper flange steel plate in step S2 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0023] Figure 4 This is a schematic diagram showing the completion of the welding of the upper flange steel plate and the shear key of the perforated plate in step S2 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0024] Figure 5 This is a schematic diagram showing the completion of the welding of the lower flange steel plate and the shear key of the perforated plate in step S2 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0025] Figure 6 This is a schematic diagram illustrating step S3 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0026] Figure 7 This is a schematic diagram illustrating step S4 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0027] Figure 8 This is a schematic diagram illustrating step S5 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0028] Figure 9 This is a schematic diagram illustrating step S6 of an embodiment 1 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0029] Figure 10 This is a side view of a second embodiment of the prestressed concrete composite beam with corrugated steel web and its construction method according to the present invention.

[0030] Figure 11 This is a finite element analysis stress diagram in the transverse direction of an embodiment 2 of the prestressed concrete composite beam with corrugated steel web and its construction method according to the present invention.

[0031] Figure 12 This is a finite element analysis stress diagram in the vertical direction of Embodiment 2 of the present invention, which describes a corrugated steel web prestressed concrete composite beam and its construction method.

[0032] Figure 13 This is a longitudinal finite element analysis stress diagram of an embodiment 2 of the prestressed concrete composite beam with corrugated steel web and its construction method according to the present invention.

[0033] Figure 14 This is a finite element analysis stress diagram in the transverse direction of a finite element model of a prestressed concrete composite beam with corrugated steel web and its construction method, which is an embodiment 2 of the present invention.

[0034] Figure 15 Example 2 of the present invention, a prestressed concrete composite beam with corrugated steel web and its construction method, shows the stress diagram of the finite element model under a uniformly distributed vertical load on the concrete top slab in the vertical direction.

[0035] Figure 16 Example 2 of the present invention, a prestressed concrete composite beam with corrugated steel web and its construction method, shows the stress diagram of the longitudinal finite element analysis of a finite element model with a uniformly distributed vertical load applied to a concrete top slab.

[0036] Figure 17 The finite element analysis stress diagram of the maximum transverse tensile stress under a uniformly distributed vertical load on the concrete top slab of a prestressed concrete composite beam with corrugated steel web and the same dimensions as the present invention, obtained by existing methods.

[0037] Figure 18 Finite element analysis stress diagram of the maximum vertical tensile stress when a uniformly distributed vertical load is applied to the concrete top slab of a prestressed concrete composite beam with corrugated steel web and the same dimensions as the present invention, obtained by existing methods.

[0038] Figure 19 Finite element analysis stress diagram of the maximum longitudinal tensile stress when a vertical uniformly distributed load is applied to the concrete top slab of a corrugated steel web prestressed concrete composite beam with the same dimensions as the present invention, obtained by existing methods.

[0039] To facilitate observation of the stress distribution of the concrete base plate in the stress diagram of finite element analysis, Figures 11-19 The corrugated steel web between the concrete top slab and the concrete bottom slab is concealed in the middle.

[0040] [Explanation of Labels in the Attached Image]

[0041] 1: Corrugated steel web;

[0042] 2: Upper flange steel plate;

[0043] 3: Lower flange steel plate; 31: Through hole;

[0044] 4: Concrete roof slab;

[0045] 5: Concrete base slab;

[0046] 6: Shear key for perforated plate;

[0047] 7: Force-applying device;

[0048] 8: Reaction frame. Detailed Implementation

[0049] To better explain and facilitate understanding of the present invention, a detailed description of the invention is provided below with reference to the accompanying drawings and specific embodiments. In this document, directional terms such as "upper" and "lower" are used interchangeably with other directional terms. Figure 3 The orientation is used as a reference.

[0050] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.

[0051] Example 1:

[0052] Reference Figures 1-9 This embodiment provides a construction method for a corrugated steel web prestressed concrete composite beam, including the following steps:

[0053] S1: Prefabricate the corrugated steel web 1, upper flange steel plate 2, lower flange steel plate 3, and perforated plate shear key 6 in the factory.

[0054] Specifically, the corrugated steel web 1 is a steel structural member processed into a corrugated shape for use as the web of a composite bridge structure. The length, width, and thickness of the corrugated steel web 1 are 20.47m, 2.5m, and 0.02m, respectively, and the material is Q345qD. The upper flange steel plate 2 and the lower flange steel plate 3 are planar plate structures. The length, width, and thickness of the upper flange steel plate 2 are 20.47m, 0.8m, and 0.024m, respectively, and the material is Q345qD. The length, width, and thickness of the lower flange steel plate 3 are 20.87m, 0.8m, and 0.024m, respectively, and the material is Q345qD. The length, width, and thickness of the perforated plate shear key 6 are 20.47m, 0.24m, and 0.016m, respectively, and the material is Q345.

[0055] Reference Figure 2A row of through holes 31 is provided at each end of the lower flange steel plate 3 along its length. All through holes 31 in each row are arranged at equal intervals along the width direction of the lower flange steel plate 3. Each through hole 31 penetrates the lower flange steel plate 3, and the axis of each through hole 31 is perpendicular to the surface of the lower flange steel plate 3. In the factory, the corresponding coordinate data of the through holes 31 are input into the CNC system of the drilling equipment to achieve drilling positioning. The operator uses a clamp to fix the lower flange steel plate 3 on the worktable to ensure that it does not shift or vibrate during the drilling process.

[0056] To prevent the through holes 31 on the lower flange steel plate 3 from deforming due to excessive tension or cracking of the hole wall due to local stress concentration, it is necessary to ensure that the spacing and diameter of the through holes 31 meet the requirements of the high-strength bolt connection specifications. That is, the spacing between two adjacent through holes 31 is less than or equal to the smaller of 7d0 or 16t, and greater than or equal to 3.5d0; the distance between the centerline of the through hole 31 and the corresponding end edge of the lower flange steel plate 3 is less than or equal to the smaller of 8t or 120mm, and greater than or equal to 1.5d0; where t refers to the thickness of the lower flange steel plate 3, which is taken as 0.024m, and d0 refers to the diameter of the through hole 31, which satisfies 10mm≤d0≤30mm.

[0057] Specifically, when the diameter d0 of the through hole 31 is 10mm and the thickness t of the lower flange steel plate 3 is 0.024m, the distance between two adjacent through holes 31 is less than or equal to 70mm and greater than or equal to 35mm; the distance between the centerline of the through hole 31 and the corresponding end edge of the lower flange steel plate 3 is less than or equal to 120mm and greater than or equal to 15mm. When the diameter d0 of the through hole 31 is 30mm and the thickness t of the lower flange steel plate 3 is 0.024m, the distance between two adjacent through holes 31 is less than or equal to 210mm and greater than or equal to 105mm; the distance between the centerline of the through hole 31 and the corresponding end edge of the lower flange steel plate 3 is less than or equal to 120mm and greater than or equal to 45mm.

[0058] After the lower flange steel plate 3 is drilled, the corrugated steel web 1, upper flange steel plate 2, lower flange steel plate 3 and perforated plate shear key 6 are transported to the construction site.

[0059] S2: Reference Figure 3 The corrugated steel web 1 is connected to the upper flange steel plate 2 by bottom welding.

[0060] In this design, the corrugated steel web 1 and the upper flange steel plate 2 have the same length direction. During overhead welding, the corrugated steel web 1 is placed vertically above the upper flange steel plate 2 and located in the middle of the upper flange steel plate 2 surface, forming an inverted T-shaped structure. The reason for choosing overhead welding is that the construction personnel can clearly observe the welding area between the corrugated steel web 1 and the upper flange steel plate 2, including the start and end points of the weld and the state of the molten pool during the welding process. This allows the construction personnel to promptly identify and adjust problems during welding, thereby improving the welding quality.

[0061] Reference Figure 4 The inverted T-shaped structure formed by the corrugated steel web 1 and the upper flange steel plate 2 is flipped into a T-shaped structure so that three prefabricated perforated plate shear keys 6 are vertically welded to the surface of the upper flange steel plate 2 away from the corrugated steel web 1, and are arranged at equal intervals on the surface of the upper flange steel plate 2 away from the corrugated steel web 1. The length direction of the perforated plate shear keys 6 is the same as the length direction of the upper flange steel plate 2, and the arrangement direction of the three perforated plate shear keys 6 is perpendicular to the length direction of the upper flange steel plate 2.

[0062] Reference Figure 5 Three perforated plate shear keys 6 are welded to the surface of the lower flange steel plate 3 using bottom welding, and are arranged at equal intervals on the surface of the lower flange steel plate 3. The width direction of the perforated plate shear keys 6 is perpendicular to the surface of the lower flange steel plate 3, and the length direction is parallel to the length direction of the lower flange steel plate 3.

[0063] Specifically, the perforated plate shear key 6 is welded to the surfaces of the upper flange steel plate 2 and the lower flange steel plate 3 as a shear connector to connect the steel beam and the concrete slab. This allows the steel beam and the concrete slab to work together as a whole, fully utilizing the tensile strength of the steel and the compressive strength of the concrete, while also transferring the longitudinal shear force between the concrete and the steel beam. It should be noted that the shear connector used in this embodiment is not limited to the perforated plate shear key 6; stud connectors, channel steel connectors, square steel connectors, T-shaped steel connectors, and bent-rib connectors can also be used to ensure that the shear force transfer requirements are met and that the connection between the steel beam and the concrete slab is effective.

[0064] S3: Reference Figure 6 Tensioning ropes are inserted into the two rows of through holes 31 at both ends of the lower flange steel plate 3, with a separate tensioning rope inserted into each through hole 31. Specifically, the tensioning ropes are steel wire ropes, which are made of multiple high-strength steel wires twisted together. These steel wire ropes possess extremely high tensile strength and good fatigue performance, ensuring that they can reliably transmit and bear the tension force, and ensuring the smooth progress of the tensioning process.

[0065] A row of through holes 31 runs along one end of the lower flange steel plate 3. Each tension rope connects to one of these through holes 31, and the two free ends of each tension rope intersect at a single point and are fixed to the reaction frame 8. The tension ropes fixed to the reaction frame 8 serve as reaction fulcrums during the tensioning process, providing stable constraints for the tension ropes in the other row of through holes 31 on the lower flange steel plate 3, ensuring that the lower flange steel plate 3 is subjected to uniform force during tensioning. Specifically, the free ends of all the tension ropes fixed to the reaction frame 8 are arranged in a row, rather than concentrated at a single point, ensuring that the tension force on each through hole 31 is evenly distributed, thus improving the stability of the tensioning process.

[0066] Each of the through holes 31 in another row on the lower flange steel plate 3 is connected to a separate tension rope. The free ends of each tension rope intersect at a point, and each tension rope is connected to a force application device 7 to uniformly tension the lower flange steel plate 3 to a uniformly distributed load of 21.02 MPa.

[0067] Specifically, the force application device 7 is a jack. The free end of each tension rope is fixed to a jack, and each jack applies the same tension to the tension rope when tensioning. Each jack pulls the tension rope connected to it at the same time until the uniform load on the lower flange steel plate 3 reaches 21.02MPa, ensuring uniform tension, maintaining the stability of the structure, and preventing the lower flange steel plate 3 from shifting during the tensioning process.

[0068] S4: Reference Figure 7 Under the uniform tension of the lower flange steel plate 3 by the force application device 7 and the reaction frame 8, and with the uniform load maintained at 21.02MPa, it is connected to the already welded T-shaped corrugated steel web 1 and upper flange steel plate 2 by bottom welding to form an I-shaped structure. The perforated plate shear key 6 on the lower flange steel plate 3 is located on the plate surface of the lower flange steel plate 3 away from the corrugated steel web 1.

[0069] Then, the perforated plate shear keys 6 on the lower flange steel plate 3 are fixed to the reinforcing bars, and formwork is installed around the lower flange steel plate 3 to provide support for concrete pouring. During the pouring process, the concrete is poured in layers and fully vibrated to ensure the compactness and uniformity of the concrete. After pouring, the concrete is cured to ensure that it reaches the design strength, ultimately forming the concrete base slab 5. Specifically, the perforated plate shear keys 6 are planar plate structures with holes arranged in a row at equal intervals along the length direction. Transverse reinforcing bars pass through the holes of the perforated plate shear keys 6, and longitudinal reinforcing bars are arranged perpendicular to the transverse reinforcing bars and fixed to the transverse reinforcing bars by stirrups to form a stable reinforcing bar skeleton. Subsequently, concrete is poured to enclose the reinforcing bar skeleton, forming the concrete base slab 5 and improving the load-bearing capacity of the structure.

[0070] Specifically, according to the design standards for concrete structures, the concrete grade of prestressed concrete structures should not be lower than C40. Therefore, the concrete base slab 5 is made of C40 grade concrete, with a length, width, and thickness of 20.47m, 1.58m, and 0.376m, respectively.

[0071] S5: Reference Figure 8 Construction workers must simultaneously and slowly release each jack to ensure that the tension force on the lower flange steel plate 3 is released evenly. After the tension force is completely released, all tension ropes are removed to release the tension on the lower flange steel plate 3 by the force application device 7 and the reaction frame 8. The purpose of simultaneous release is to prevent the structure from twisting or local stress concentration due to uneven release of tension force.

[0072] After the tension is released, a pre-bending force can be introduced into the entire corrugated steel web prestressed concrete composite beam, causing the lower flange steel plate 3, the upper flange steel plate 2 and the corrugated steel web 1 to bend to different degrees. In the subsequent service stage, the pre-bending force can cancel or superimpose the stress generated by the external load, thereby optimizing the stress performance of the structure and improving its load-bearing capacity.

[0073] The perforated plate shear keys 6 on the upper flange steel plate 2 are fixed to the reinforcing bars. Formwork is installed around the upper flange steel plate 2 to provide support for concrete pouring. During pouring, the amount of concrete poured and the degree of vibration are controlled to ensure the compactness and uniformity of the concrete. After pouring, the concrete is cured to ensure it reaches its design strength, ultimately forming the concrete top slab 4.

[0074] Specifically, according to the design standards for concrete structures, the concrete grade of prestressed concrete structures should not be lower than C40. Therefore, C40 grade concrete is selected for the concrete roof slab, with a length, width, and thickness of 20.47m, 2.38m, and 0.376m, respectively.

[0075] Specifically, the positional relationship between the perforated plate shear key 6 on the upper flange steel plate 2 and the longitudinal reinforcement, transverse reinforcement, and stirrups is the same as that between the perforated plate shear key 6 on the lower flange steel plate 3 and the longitudinal reinforcement, transverse reinforcement, and stirrups, and will not be repeated here.

[0076] The lower flange steel plate 3 has 20cm of extra steel plate at each end for tensioning. Therefore, the tensioning steel plate must be avoided during casting. The casting area is the area between the two rows of through holes 31 on the lower flange steel plate 3, and the tensioning area is the area between the two rows of through holes 31 on the lower flange steel plate 3 and the corresponding ends.

[0077] S6: Reference Figure 9The end region containing the two rows of through holes 31 on the lower flange steel plate 3 is cut off. Removing the steel plate in the tensioning area eliminates potential safety hazards and avoids adverse effects on the structure, thus completing the fabrication of the corrugated steel web prestressed concrete composite beam.

[0078] Example 2:

[0079] Reference Figure 10 This embodiment provides a corrugated steel web prestressed concrete composite beam, which is manufactured using the construction method of Embodiment 1. It includes a corrugated steel web 1, an upper flange steel plate 2, a lower flange steel plate 3, a concrete top plate 4, a concrete bottom plate 5, and a perforated plate shear key 6.

[0080] The corrugated steel web 1, upper flange plate 2, and lower flange plate 3 are all of equal length. The upper flange plate 2 and lower flange plate 3 are parallel, and their projections in the direction perpendicular to the surface of the lower flange plate 3 coincide. The upper flange plate 2 and lower flange plate 3 are separated by a certain distance, which is equal to the height of the corrugated steel web 1. The corrugated steel web 1 is welded to the two opposite surfaces of the upper flange plate 2 and lower flange plate 3.

[0081] The concrete top slab 4 is connected to the upper surface of the upper flange steel plate 2 via the perforated plate shear key 6 on the upper flange steel plate 2 and the reinforcing bars passing through the perforated plate shear key 6. The concrete bottom slab 5 is connected to the lower surface of the lower flange steel plate 3 via the perforated plate shear key 6 on the lower flange steel plate 3 and the reinforcing bars passing through the perforated plate shear key 6.

[0082] The corrugated steel web prestressed concrete composite beam introduces initial stress into the beam by pre-tensioning the lower flange steel plate 3, which makes it have higher bending strength and bearing capacity when bearing external loads, and reduces the risk of deflection and cracking.

[0083] To verify the mechanical properties and structural reliability of the corrugated steel web prestressed concrete composite beam of Example 2 obtained by the construction method of Example 1 in actual use, the tensile stress of its concrete was simulated and evaluated by the finite element analysis method.

[0084] According to step S3 of the construction method in Example 1, a uniformly distributed load of 21.02 MPa was applied to the uniformly tensioned lower flange steel plate 3. In step S4, while maintaining the uniform load tension, the lower flange steel plate 3 was welded to the T-shaped corrugated steel web 1 and upper flange steel plate 2, and a concrete base slab 5 was poured. In step S5, the tension on the lower flange steel plate 3 was released, the uniform load was released, and a pre-bending force was introduced into the corrugated steel web prestressed concrete composite beam, causing the lower flange steel plate 3, upper flange steel plate 2, and corrugated steel web 1 to bend to different degrees. The pre-bending force could offset the stress generated by the external load, and a concrete top slab 4 was poured on the upper flange steel plate 2. Furthermore, it is necessary to determine whether the established finite element model of the corrugated steel web prestressed concrete composite beam conforms to the General Specifications for Composite Structures (GB55004-2021), the Design Specifications for Steel-Concrete Composite Bridges (GB 50917-2013), and the Design and Construction Specifications for Highway Steel-Concrete Composite Bridges (JTG). Therefore, it is necessary to use the finite element model to calculate the initial stress state of the corrugated steel web prestressed concrete composite beam after construction (D64-2015).

[0085] During the finite element analysis, a uniformly distributed load of 21.02 MPa was applied to the lower flange steel plate 3 according to step S3 of the construction method in Example 1. After establishing the finite element model of the corrugated steel web prestressed concrete composite beam, the initial stress distribution of the corrugated steel web prestressed concrete composite beam in Example 2 after manufacturing was simulated based on the finite element analysis. According to its initial stress distribution diagram, it was determined that the established finite element model conforms to the General Specification for Composite Structures (GB55004-2021), the Design Specification for Steel-Concrete Composite Bridges (GB 50917-2013), and the Design and Construction Specification for Highway Steel-Concrete Composite Bridges (JTG D64-2015). (Refer to...) Figure 11 The maximum transverse tensile stress is 0.14 MPa; refer to Figure 12 The maximum vertical tensile stress is 0.50 MPa; refer to Figure 13 The maximum longitudinal tensile stress is 0.41 MPa.

[0086] To compare and analyze the stress performance of corrugated steel web composite beams manufactured by two methods (the construction method of Example 1 and the existing construction method) under the same load, the same 20 kN / m² load was applied to the concrete top slab 4 of both finite element models of corrugated steel web prestressed concrete composite beams manufactured by the construction method of Example 1 and the existing construction method. 2 A vertical uniformly distributed load is applied to simulate the stress distribution of both components under the aforementioned load.

[0087] In a prestressed concrete composite beam with corrugated steel web under load, the concrete top slab 4 can transfer the load to the concrete bottom slab 5 through the corrugated steel web 1. Therefore, the concrete bottom slab 5 is the main tensile member, and its tensile stress level directly determines the crack resistance of the structure. Table 1 lists the maximum tensile stresses in the transverse, vertical, and longitudinal directions of the concrete bottom slab 5 in the finite element models of the prestressed concrete composite beam with corrugated steel web obtained by the two methods under the above load.

[0088] Table 1. Comparison of maximum tensile stress in the concrete base plate of corrugated steel web composite beams under two construction methods (unit: MPa)

[0089] Construction method of Example 1 Existing construction methods Maximum transverse tensile stress 0.35 0.59 Maximum vertical tensile stress 0.65 0.42 Maximum longitudinal tensile stress 0.86 1.81

[0090] Note: The stress distribution of the construction method in Example 1 is as follows. Figure 14 (maximum tensile stress in the transverse direction) Figure 15 (maximum vertical tensile stress) Figure 16 (Maximum longitudinal tensile stress); Stress distribution in existing construction methods (reference) Figure 17 (maximum tensile stress in the transverse direction) Figure 18 (maximum vertical tensile stress) Figure 19 (Maximum longitudinal tensile stress).

[0091] Known Figures 11-19 In the legend in the upper left corner, positive values ​​represent tensile stress, and negative values ​​represent compressive stress. (Compare...) Figure 16 and Figure 19 , Figure 16 The yellow area of ​​the concrete base slab 5 is significantly larger than Figure 19 The yellow area in the concrete base slab 5 is small, indicating that the maximum longitudinal tensile stress of the corrugated steel web prestressed concrete composite beam obtained without the construction method of Example 1 is significantly greater than that of the corrugated steel web prestressed concrete composite beam obtained with the construction method of Example 1.

[0092] The critical condition for concrete cracking is that the tensile stress reaches the tensile strength of the concrete. That is, under the same load, the smaller the maximum tensile stress, the less likely it is to reach the cracking limit. The analysis results show that the method in this embodiment effectively reduces the longitudinal tensile stress level of the concrete base slab in the key stress direction, thereby significantly alleviating the tensile stress in the concrete in the main stress direction of the corrugated steel web concrete composite beam, limiting concrete cracking, and improving the structural bearing capacity.

[0093] In the description of this invention, it should be understood that 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 indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0094] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," 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.

[0095] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," or "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," or "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0096] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "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, illustrative expressions of the above terms must 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.

[0097] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A construction method for a corrugated steel web prestressed concrete composite beam, characterized in that, A corrugated steel web prestressed concrete composite beam includes a corrugated steel web, an upper flange steel plate, a lower flange steel plate, a concrete top slab, a concrete bottom slab, and a perforated plate shear key; The construction method includes the following steps: S1: Prefabricate an upper flange steel plate, a corrugated steel web plate, and a lower flange steel plate. A row of through holes is provided at each end of the lower flange steel plate along its length direction. All through holes in each row are spaced apart along the width direction of the lower flange steel plate. Each through hole penetrates the lower flange steel plate along its thickness direction. S2: Weld the corrugated steel web to the upper flange steel plate, weld perforated shear keys to the upper flange steel plate on the surface away from the corrugated steel web, and weld perforated shear keys to the lower flange steel plate; the upper flange steel plate and the lower flange steel plate are parallel and spaced apart, and the corrugated steel web is vertically welded between the two opposite surfaces of the upper flange steel plate and the lower flange steel plate; S3: Tension ropes are inserted into both rows of through holes. The tension ropes connected to one row of through holes are fixed, and the tension ropes connected to the other row of through holes are connected to a force application device to uniformly tension the lower flange steel plate to the design load. S4: When the lower flange steel plate is under tension, it is welded to the corrugated steel web and the upper flange steel plate that have been welded together to form an I-shaped structure. The perforated shear key on the lower flange steel plate is located on the surface of the lower flange steel plate away from the corrugated steel web. Then, the perforated shear key on the lower flange steel plate is fixed to the reinforcing bars, and concrete is poured to form a concrete base slab. The pouring area is the area between the two rows of through holes on the lower flange steel plate. The perforated shear key on the upper flange steel plate is perpendicular to it, and the extension direction of the perforated shear key is the same as the length direction of the upper flange steel plate. The perforated shear key on the lower flange steel plate is also perpendicular to it, and the extension direction of the perforated shear key is the same as the length direction of the lower flange steel plate. S5: Release the tension on the lower flange steel plate, fix the perforated plate shear key and the reinforcing bar on the upper flange steel plate, and pour concrete to form a concrete top plate; the concrete top plate is connected to the upper plate surface of the upper flange steel plate through the perforated plate shear key and the reinforcing bar, and the concrete bottom plate is connected to the lower plate surface of the lower flange steel plate through the perforated plate shear key and the reinforcing bar. S6: Cut off the end area where the two rows of through holes are located on the lower flange steel plate to complete the fabrication of the corrugated steel web prestressed concrete composite beam.

2. The construction method of a corrugated steel web prestressed concrete composite beam as described in claim 1, characterized in that, In step S2, the welding of the corrugated steel web and the upper flange steel plate, the welding of the upper flange steel plate and the shear key of the perforated plate, and the welding of the lower flange steel plate and the perforated plate all adopt double-sided fillet welds. The welding of the lower flange steel plate and the corrugated steel web and the upper flange steel plate that have been welded together in step S4 is a double-sided fillet weld.

3. The construction method of a corrugated steel web prestressed concrete composite beam as described in claim 1, characterized in that, Both rows of through holes are circular through holes arranged linearly at equal intervals. The distance between two adjacent through holes is less than or equal to the smaller of 7d0 or 16t, and greater than or equal to 3.5d0. The distance between the centerline of the through hole and the corresponding end edge of the lower flange steel plate is less than or equal to the smaller of 8t or 120mm, and greater than or equal to 1.5d0; Where t refers to the thickness of the lower flange steel plate, and d0 refers to the diameter of the through hole.

4. The construction method of a corrugated steel web prestressed concrete composite beam as described in claim 3, characterized in that, The diameter d0 of the through hole satisfies: 10mm≤d0≤30mm.

5. The construction method of a corrugated steel web prestressed concrete composite beam as described in claim 1, characterized in that, In step S3, the tension ropes connected to one row of through holes are fixed on the reaction frame, and the free ends of the tension ropes are arranged in a row. The tension ropes connected to each of the through holes in the other row are connected to a force application device to uniformly tension the lower flange steel plate to the design load.

6. The construction method of a corrugated steel web prestressed concrete composite beam as described in claim 1, characterized in that, In step S3, the tension ropes connected to a row of through holes are fixed on the reaction frame, and the force application device is a jack, with one tension rope corresponding to one independent jack.

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