A partially filled simply supported high-strength steel tube truss structure and its fabrication method

Abstract

This invention relates to a partially filled simply supported high-strength steel tubular truss structure, comprising compression chords, tension chords, web members, and lower end bracing. The compression and tension chords are internally reinforced with perforated steel plate stiffeners. The compression chords are filled with HSC (high-strength concrete) throughout their length. The tension chords are filled with ordinary concrete in the support sections, and the lower end bracing and the web members in the support sections are also filled with ordinary concrete. These structures and measures can significantly improve the strength, stiffness, and load-bearing capacity of the truss, reduce the cross-sectional height and member dimensions, and enhance the spanning capacity of such trusses.

Description

Technical Field

[0001] This invention relates to a partially filled simply supported high-strength steel tube truss structure and its manufacturing method, and relates to the field of bridge engineering. Background Technology

[0002] Ordinary steel pipe trusses refer to integral bending members in which the tension chords, compression chords, web members, and tie rods are all made of ordinary hollow steel pipes, and the chords and web members are welded together (generally used to bear nodal loads). Figure 1 , 2 As shown.

[0003] The main disadvantages of ordinary steel pipe trusses:

[0004] (1) Compression chords are not suitable for bearing the load of the superstructure. Ordinary hollow steel tubes used in compression chords are prone to local buckling under the load of the superstructure, which affects the overall bearing capacity and stiffness of the truss.

[0005] (2) The forces acting on the tension chord and web members near the fulcrum are both very unfavorable:

[0006] ① When it is a simply supported structure, the tension chord of a common steel pipe truss will be subjected to a large support reaction force near the support point. Under the action of web member compression, the chord may undergo plastic yielding, punching shear failure or even local buckling; under the action of web member tension, the chord may undergo tensile failure or excessive pear-shaped deformation.

[0007] ② Near the support, the truss is subjected to large shear forces. When the web members are under tension, the web member joints may crack locally; when the web members are under compression, the web member joints may yield locally or even buckle locally.

[0008] (3) The truss has low bending capacity. When the span increases, the material strength is difficult to meet the design requirements for bending capacity. If the cross section is increased, the elevation or clearance will not meet the requirements.

[0009] The prestressed steel pipe truss composite simply supported beam structure is described in patent application number 2012100303946. It mainly comprises compression chords, tension chords, and web members. All steel pipes are made of ordinary steel. Prestressing tendons are installed within the tension chords, and prestressing tendon guide devices are installed at each node. The purpose of applying prestress to the tension chords is primarily to improve bending capacity and bending stiffness, and to reduce the structure's self-weight. The construction steps include: 1. Welding the compression chords, tension chords, and web members to form the main beam skeleton; 2. Installing guide devices at each node within the tension chords; 3. Laying prestressing tendons within the tension chords, and simultaneously tensioning and anchoring them at both ends; 4. Bridge deck construction.

[0010] The main disadvantages of prestressed steel pipe truss composite simply supported beam structures are:

[0011] (1) The construction cost is high and the construction period is long.

[0012] ① The process of tensioning prestressed concrete is complex and the construction is cumbersome. It requires specialized tensioning equipment and construction teams, which leads to increased costs for machinery and equipment and labor.

[0013] ② Setting up guiding devices at each node within the tension chord presents challenges in positioning and complicates the construction process.

[0014] (2) Durability issues of prestressed structures.

[0015] ① The prestressed anchor head is installed at the end of the chord steel pipe, which requires special durability design, increasing the difficulty of corrosion prevention and maintenance costs;

[0016] ② The tension chord is an empty steel pipe, and the prestressing tendons are exposed to the air, which makes them prone to corrosion and affects the long-term use of the structure.

[0017] (3) The support is not subjected to stress. The bending deformation of the truss causes the support section to rotate, which will cause the contact between the support and the foundation to change from a vertical surface contact to an inclined line contact or even a point contact, which is unfavorable to the stress and deformation of the support. Summary of the Invention

[0018] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a partially filled simply supported high-strength steel pipe truss structure and its manufacturing method.

[0019] To solve the above-mentioned technical problems, the technical solution of the present invention is: a partially filled simply supported high-strength steel pipe truss structure, including a compression chord, a tension chord, web members, and a lower end tie rod. The compression chord and tension chord are internally fixed with perforated steel plate stiffening ribs. The compression chord is internally filled with HSC throughout. The tension chord is internally filled with ordinary concrete in the support section. The lower end tie rod and the web members in the support section are also filled with ordinary concrete.

[0020] Preferably, the compression chord, tension chord, and web members are all made of high-strength steel pipes, while the lower end flat bracing is made of ordinary steel pipes.

[0021] Preferably, at the fulcrum, the tension chord and the web member converge on the lower horizontal bracing, which is supported on a support; the diameter of the lower horizontal bracing is larger than the diameter of the chord and the web member.

[0022] Preferably, the perforated steel plate stiffening ribs are welded to the chord members only in the nodal domain of the truss.

[0023] Preferably, the web members are welded to both the compression chord and the tension chord, and except for the web members that need to be filled with concrete and require holes to be drilled at the corresponding positions of the chords, the other web members are not connected to the chords.

[0024] Preferably, the compression chord, tension chord, and lower end flat brace are all provided with through holes aligned with the axis of the web member near the fulcrum, and the lower end flat brace is provided with a through hole aligned with the axis of the tension chord.

[0025] Preferably, a partition steel plate is fixed inside the tension chord, and the partition steel plate is located at the ordinary concrete end away from the lower horizontal coupling.

[0026] Preferably, both the compression chord and the tension chord tube have U-shaped locking bars welded at the chord joint, and the U-shaped locking bars at the chord joint are staggered and positioned by clamping during construction.

[0027] A method for fabricating a partially infilled simply supported high-strength steel pipe truss structure, comprising the following steps:

[0028] (1) Make through holes by aligning the pipe walls of the compression chord, tension chord, and lower end horizontal bracing with the axis of the web members near the fulcrum, for pouring ordinary concrete into the tension chord, lower end horizontal bracing, and web members near the fulcrum, and ensure air permeability during the pouring process.

[0029] (2) After welding U-shaped locking steel bars inside the tube at the joint of the chord, the joint is then made. Then, a continuous perforated steel plate stiffening rib is set in the compression chord and tension chord, and welded to the steel pipe in the node area.

[0030] (3) A through hole is made at the intersection of the pipe wall of the lower horizontal connection and the axis of the tension chord for pouring ordinary concrete;

[0031] (4) The compression chord, tension chord, web members and lower end flat bracing are welded together to form a space steel tube truss;

[0032] (5) Raise one side of the tension chord and pump ordinary concrete into it through the through hole. After the concrete fills the tension chord and the lower end flat joint, it will rise continuously along the web through the through hole until the ordinary concrete grout is observed to emerge in the compression chord.

[0033] (6) Raise one side of the compressed chord and inject HSC into the compressed chord.

[0034] Preferably, when welding the stiffening ribs of the perforated steel plate inside the chord, the ribs are first positioned by spot welding, and then an automatic welding carriage or automatic welding gun is used to enter the pipe for welding.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (i) High structural bearing capacity and high stiffness.

[0037] 1. This application fills the tension chord section and web members near the support with ordinary concrete to improve the bearing capacity and stiffness of the tension chord and web members near the support;

[0038] 2. This application provides a continuous perforated steel plate stiffening rib inside the chord, which, while providing stiffening, can reduce the voids and relative slippage at the steel-concrete interface, thereby improving the load-bearing capacity and stiffness of the chord and joints;

[0039] 3. The application of filling the compression chord with HSC can not only assist the chord steel tube in bearing the force, but also improve the strength and stiffness of the joint, and help stabilize the perforated steel plate stiffening ribs so as to exert their stiffening effect.

[0040] 4. This application increases the diameter of the lower end flat tie and pours ordinary concrete into the pipe, which can improve the overall structure and improve the stress state of the tension chord.

[0041] (ii) Strong structural cross-span capability.

[0042] The chords in this application are made of high-strength steel, with continuous perforated steel plate stiffeners installed inside the tubes (welded to the steel tubes only in the node area). The compression chord tubes are filled with HSC, and the sections near the supports of the tension chords are filled with ordinary concrete. This can improve the bearing capacity and stiffness of the chords and nodes, thereby improving the overall bending bearing capacity and stiffness of the truss. In actual engineering, while meeting the structural bearing capacity requirements, the cross-sectional height and member size can be reduced, thus improving the spanning capacity of the structure.

[0043] (iii) High material utilization rate.

[0044] 1. In order to adapt to changes in axial force, the wall thickness of the chord steel pipe is greater closer to the mid-span, and the wall thickness of the web steel pipe is greater closer to the support point, so as to make full use of the material;

[0045] 2. In this application, HSC is filled in the compression chord members where the concrete plays a greater role, while ordinary concrete is filled only in the section near the support where the tension chord members are under greater stress.

[0046] (iv) The construction is simple and the quality is controllable.

[0047] 1. This application uses high-strength materials, which can reduce the self-weight of the structure while ensuring the structural bearing capacity, making construction and lifting easier. At the same time, it can avoid the use of construction techniques such as applying prestress, thereby reducing construction costs and shortening the construction period.

[0048] 2. The continuous perforated steel plate stiffening ribs provided in the chord of this application are only welded to the chord steel pipe in the node area, which can greatly reduce the amount of welding work, reduce the heat-affected zone of welding, and simplify the construction positioning.

[0049] 3. The chord butt joint structure adopted in this application is simple to construct and accurate in positioning. The U-shaped interlocking steel bar itself can improve the vertical shear stiffness of the steel pipe at the weld, and at the same time, it can allow concrete aggregate to enter the intersection area of ​​the U-shaped interlocking steel bar to form a concrete tenon, which plays an anchoring role.

[0050] (v) It has strong structural integrity and stability, and good dynamic characteristics.

[0051] 1. This application increases the diameter of the lower end bracing, so that the web members near the support and the lower chord members converge on the lower end bracing. This not only prevents the chord members from contacting the support, reducing the adverse effects of local stress caused by the support reaction force to improve the stress state of the tension chord members, but also allows the structure to be connected as a whole by the strong lower end bracing, improving the lateral bending stiffness and torsional stiffness of the structure, thereby improving the overall integrity of the structure.

[0052] 2. The lower end of the horizontal bracing is supported on the support, and the force between the lower end of the horizontal bracing steel pipe and the support is always kept in the vertical direction (radial direction of the lower end of the horizontal bracing steel pipe), thereby reducing the shear deformation of the support caused by the bending of the truss and improving the stress state of the support.

[0053] 3. Filling the lower end of the horizontal connecting pipe with concrete can lower the center of gravity of the structure, improve the stability of the structure, increase the damping ratio of the structure, and improve the dynamic characteristics of the structure.

[0054] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0055] Figure 1 The image shows an elevation view of a common steel pipe truss in the background art.

[0056] Figure 2 for Figure 1 Section I-I.

[0057] Figure 3 This is an elevation view of an embodiment of the present invention.

[0058] Figure 4 for Figure 3 Section II-II diagram.

[0059] Figure 5 for Figure 3 Section III-III diagram.

[0060] Figure 6 Front view of the stiffening ribs of the perforated steel plate.

[0061] Figure 7 Side view of the stiffening ribs in the perforated steel plate.

[0062] Figure 8 Side view of the chord joint construction.

[0063] Figure 9 for Figure 8 Section IV-IV.

[0064] In the figure: 1-Compression chord; 2-Stiffening rib with perforated steel plate; 3-Web member; 4-Tension chord; 5-Through hole in chord; 6-Partition steel plate; 7-Lower end bracing; 8-Through hole in lower end bracing; 9-Ordinary concrete; 10-HSC; 11-U-shaped interlocking steel bar. Detailed Implementation

[0065] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0066] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0067] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0068] like Figures 1-9 As shown, this application can solve the following technical problems of the two existing technical solutions:

[0069] 1. To address the problem that ordinary steel pipe truss compression chords are not suitable for bearing vertical loads transmitted from the superstructure, this application adopts filling the compression chords with high-strength concrete (HSC) to improve the vertical shear stiffness and bending stiffness of the compression chords. This allows the compression chords to directly bear vertical loads, similar to solid web beams, without the need for local stiffening at the load-transmitting nodes.

[0070] 2. To address the problem of unfavorable stress distribution in tension chords and web members near the supports of ordinary steel pipe trusses, this application adopts the following measures to solve or improve the situation:

[0071] (1) Install continuous stiffening ribs inside the tension chord tube (welded only in the node area) and fill the section near the support with ordinary concrete;

[0072] (2) Fill the web tube near the fulcrum with ordinary concrete;

[0073] (3) Enlarge the diameter of the lower end parallel coupling pipe and pour ordinary concrete into the pipe to improve the stress state of the tension chord, parallel coupling and web members near the support.

[0074] 3. This application addresses the issue of low bending capacity or low elevation clearance in steel pipe trusses. High-strength steel is used for both tension and compression chords, and continuous stiffening ribs are installed inside the tubes (welded to the steel pipes only at the nodes). HSC is filled inside the compression chord tubes, and ordinary concrete is filled in the section near the support of the tension chord. This can improve the bearing capacity and stiffness of the chords and nodes, thereby improving the overall bending capacity and stiffness of the truss without increasing the cross-sectional height of the truss beams or the size of the members.

[0075] 4. In view of the problems of increased construction costs, extended construction period and corrosion of prestressing tendons caused by prestressing, this application does not use prestressing. Instead, in view of the design purpose of prestressing to improve the structural bending capacity and stiffness, this application solves the problem through the measures in Article 3.

[0076] 5. To address the problem of unfavorable stress on the support, this application adopts a lower horizontal connector with an increased diameter and ordinary concrete is poured into the pipe. The lower horizontal connector is supported on the support. The force between the lower horizontal connector steel pipe and the support is always kept in the vertical direction (radial direction of the lower horizontal connector steel pipe), thereby reducing the shear deformation of the support caused by the bending of the truss and improving the stress state of the support.

[0077] This embodiment provides a partially filled simply supported high-strength steel tube truss structure, including a compression chord, a tension chord, web members, and a lower end tie. The compression chord and tension chord are internally fixed with perforated steel plate stiffeners. The compression chord is internally filled with HSC throughout. The tension chord is internally filled with ordinary concrete in the support section. The lower end tie and the web members in the support section are also filled with ordinary concrete.

[0078] In this embodiment of the invention, the compression chord, tension chord, and web members are all made of high-strength steel pipes, while the lower end flat bracing is made of ordinary steel pipes.

[0079] In this embodiment of the invention, at the fulcrum, the tension chord and the web member converge on the lower horizontal bracing, which is supported on the support; the diameter of the lower horizontal bracing is larger than the diameter of the chord and the web member.

[0080] In this embodiment of the invention, the perforated steel plate stiffening rib is welded to the chord only at the node region of the truss.

[0081] In this embodiment of the invention, the web members are welded to both the compression chord and the tension chord, and except for the web members that need to be filled with concrete and require holes to be drilled at the corresponding positions of the chords, the other web members are not connected to the chords.

[0082] In this embodiment of the invention, the compression chord, tension chord, and lower end flat connector are all provided with through holes along the axis of the web member near the fulcrum, and the lower end flat connector is provided with a through hole along the axis of the tension chord.

[0083] In this embodiment of the invention, a partition steel plate is fixed inside the tension chord, and the partition steel plate is located at the ordinary concrete end away from the lower horizontal connection.

[0084] In this embodiment of the invention, both the compression chord and the tension chord tube have U-shaped locking steel bars welded at the chord joint. The U-shaped locking steel bars at the chord joint are staggered and are positioned by clamping during construction.

[0085] In this embodiment of the invention, the wall thickness of the chord steel pipe is greater closer to the mid-span, and the wall thickness of the web steel pipe is greater closer to the fulcrum.

[0086] In this embodiment of the invention, to adapt to changes in axial force, the wall thickness of the chord steel tube is greater closer to the mid-span, and the wall thickness of the web steel tube is greater closer to the support point. The joint structure of chords with different wall thicknesses is as follows: Figure 8 , 9 As shown. The chord steel pipe butt joint is located between sections, avoiding the node area. Before butt jointing, the staggered U-shaped locking bars on the inner wall of the steel pipe are used for positioning. Then, a V-shaped bevel full penetration butt weld is used for connection. The starting and ending points of the weld should avoid the upper and lower edges of the chord steel pipe. The distance L from the weld between the U-shaped locking bar and the steel pipe to the butt weld of the steel pipe is ≥ 50mm. The straight section length L1 of the U-shaped locking bar is L1 = D, where D is the diameter of the chord steel pipe (D... c Or D t ).

[0087] This application describes perforated steel plate stiffeners installed along the entire length of the chord steel tube. These stiffeners improve the strength and stiffness of the joint and assist the chord steel tube in bearing stress. For compression chords, the bonding effect between the perforated steel plate stiffeners and the concrete filling inside the tube mainly includes the interlocking force between the concrete aggregates within the perforation, as well as the frictional and chemical bonding forces at the steel-concrete interface. The perforated steel plate stiffeners are welded to the inner wall of the steel tube only at the joint area. The structure of the perforated steel plate stiffeners is as follows... Figure 6 , 7 As shown, the height h = 0.3D, the thickness t = D / 30, the hole diameter d = 0.1D, and the hole spacing s = 0.2D, where D is the diameter of the chord steel pipe (D c Or D t ).

[0088] This application utilizes HSC filling within the compression chord tube, which assists in the stress distribution of the chord tube, improves the strength and stiffness of the joint, and helps stabilize the perforated stiffeners to fulfill their stiffening function. Filling the tension chord section and web tube near the support with ordinary concrete can improve the load-bearing capacity and stiffness of the tension chord and web members.

[0089] This application increases the diameter of the lower end tie rod, allowing the web members near the support and the lower chord members to converge on the lower end tie rod. This not only prevents the chord members from contacting the support, reducing the adverse effects of local stress caused by the support reaction and improving the stress state of the tension chord members, but also utilizes the strong end tie rod to connect the structure as a whole, increasing the lateral bending stiffness and torsional stiffness of the structure, thereby improving the overall structural integrity. By supporting the lower end tie rod on the support, the force between the lower end tie rod steel pipe and the support remains vertical (radial direction of the lower end tie rod steel pipe), thereby reducing the shear deformation of the support caused by the bending of the truss beam and improving the stress state of the support. Filling the lower end tie rod with concrete can lower the center of gravity of the structure, improve the stability of the structure, and increase the damping ratio of the structure, improving the dynamic characteristics of the structure.

[0090] A method for fabricating a partially infilled simply supported high-strength steel pipe truss structure, comprising the following steps:

[0091] (1) Make through holes by aligning the pipe walls of the compression chord, tension chord, and lower end horizontal bracing with the axis of the web members near the fulcrum, for pouring ordinary concrete into the tension chord, lower end horizontal bracing, and web members near the fulcrum, and ensure air permeability during the pouring process.

[0092] (2) After welding U-shaped locking steel bars inside the tube at the chord joint, the joint is made (the partition steel plate is welded to the U-shaped locking steel bars and then extended into the tension chord). Then, a continuous perforated steel plate stiffening rib is set in the compression chord and tension chord and welded to the steel pipe in the node area.

[0093] (3) Two through holes are made at the intersection of the pipe wall of the lower horizontal connection and the axis of the tension chord for pouring ordinary concrete.

[0094] (4) The compression chord, tension chord, web members and lower end flat bracing are welded together to form a space steel tube truss;

[0095] (5) Raise one side of the tension chord and pump ordinary concrete into it through the through hole. After the concrete fills the tension chord and the lower end flat joint, it will rise continuously along the web through the through hole until the ordinary concrete grout is observed to emerge in the compression chord (the construction method of pumping concrete on the other side is the same as above).

[0096] (6) Raise one side of the compressed chord and inject HSC into the compressed chord.

[0097] In this embodiment of the invention, when welding the stiffening ribs of the perforated steel plate inside the chord, the ribs are first positioned by spot welding, and then the automatic welding carriage or automatic welding gun is used to enter the tube for welding (if the length of the member is large, it can be entered for welding from both ends).

[0098] This application employs the method of filling the tension chord section and web members near the support with ordinary concrete to improve the load-bearing capacity and stiffness of the tension chords and web members near the support; it also adopts the method of setting continuous stiffening ribs inside the chords (welded to the steel pipe only in the joint area), which significantly reduces the amount of welding work and the heat effect of welding during construction; in terms of stress, while providing stiffening function, it can reduce the voids and relative slippage at the steel pipe-concrete interface, thereby improving the load-bearing capacity and stiffness of the chords and joints; and it adopts a butt joint structure for the chords, which facilitates construction. The U-shaped interlocking reinforcement facilitates positioning and reduces construction difficulty. In terms of stress, the U-shaped interlocking reinforcement itself increases the vertical shear stiffness of the steel pipe at the weld, while allowing concrete aggregate to enter the intersecting area of ​​the U-shaped interlocking reinforcement to form a concrete tenon, thus providing anchorage. This application increases the diameter of the lower end bracing, causing the web members and lower chord members near the support to converge on the lower end bracing. This not only prevents the chord members from contacting the support, reducing the adverse effects of local stress caused by the support reaction and improving the stress state of the tension chord members, but also utilizes the strong end bracing to connect the structure into a whole. The structure is improved by increasing its lateral bending and torsional stiffness, thereby enhancing its overall integrity. The lower horizontal bracing is supported on the bearings, ensuring the force between the lower horizontal bracing pipe and the bearing remains vertical (radial towards the lower horizontal bracing pipe), thus reducing shear deformation at the bearings caused by truss bending and improving the bearing's stress state. Filling the lower horizontal bracing pipe with concrete lowers the center of gravity, improving stability, and increases the damping ratio, thus improving dynamic characteristics. Based on the axial force variation law of the chord members, the chord members and web members are adjusted along the span... Different wall thicknesses are used in the radial direction to make full use of the material; the method of grouting HSC in the compression chord can not only assist the chord steel tube in bearing the force, but also improve the strength and stiffness of the joint, and help stabilize the perforated stiffening rib to exert its stiffening effect; the chord and web members are made of high-strength steel, and HSC is filled in the compression chord tube, while ordinary concrete is filled in the tension chord tube only in the section near the support, thereby greatly improving the strength, stiffness and load-bearing capacity of the truss, reducing the cross-sectional height and member size, and improving the spanning capacity of this type of truss.

[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A partially filled simply supported high-strength steel pipe truss structure, comprising compression chords, tension chords, web members, and lower end tie rods, characterized in that: The compression chord and tension chord are internally fixed with perforated steel plate stiffeners along their entire length. The compression chord is filled with HSC throughout its entire length, while the tension chord is filled with ordinary concrete in the support section, and the lower end tie and the web members in the support section are also filled with ordinary concrete. The compression chord, tension chord, and web members are all made of high-strength steel pipes, while the lower end tie is made of ordinary steel pipe. At the support, the tension chord and web members converge on the lower end tie, which is supported by a bearing. The diameter of the lower end tie is larger than that of the chord and web members. The perforated steel plate stiffeners are welded to the chords only at the nodes of the truss beam. The web members are welded to both the compression chord and the tension chord, and except for the web members that require concrete filling and need to have holes drilled at corresponding positions on the chords, the other web members are not continuous with the chords; the compression chord, tension chord, and lower end tie rod all have through holes aligned with the axis of the web members near the fulcrum, and the lower end tie rod also has a through hole aligned with the axis of the tension chord; a partition steel plate is fixed inside the tension chord, located at the ordinary concrete end away from the lower end tie rod; U-shaped locking bars are welded inside the compression chord and tension chord tubes at the chord joints, and the U-shaped locking bars at the chord joints are staggered and positioned by clamping during construction.

2. A method for manufacturing a partially filled simply supported high-strength steel pipe truss structure as described in claim 1, characterized in that, Follow these steps: (1) Make through holes by aligning the pipe walls of the compression chord, tension chord, and lower end horizontal bracing with the axis of the web members near the fulcrum, for pouring ordinary concrete into the tension chord, lower end horizontal bracing, and web members near the fulcrum, and ensure air permeability during the pouring process. (2) After welding U-shaped locking steel bars inside the tube at the joint of the chord, the joint is then made. Then, a continuous perforated steel plate stiffening rib is set in the compression chord and tension chord, and welded to the steel pipe in the node area. (3) A through hole is made at the intersection of the pipe wall of the lower horizontal connection and the axis of the tension chord for pouring ordinary concrete; (4) The compression chord, tension chord, web members and lower end flat bracing are welded together to form a space steel tube truss; (5) Raise one side of the tension chord and pump ordinary concrete into it through the through hole. After the concrete fills the tension chord and the lower end flat joint, it will rise continuously along the web through the through hole until the ordinary concrete grout is observed to emerge in the compression chord. (6) Raise one side of the compressed chord and inject HSC into the compressed chord.

3. The method for fabricating a partially filled simply supported high-strength steel pipe truss structure according to claim 2, characterized in that: When welding the stiffening ribs of the steel plate with openings inside the chord, first use spot welding for positioning, and then use an automatic welding carriage or automatic welding gun to enter the pipe for welding.

Images