U-rib assembly for a steel bridge in service

Abstract

This application relates to the field of welding technology, and in particular to a U-rib assembly for in-service steel bridges, comprising a body and a U-rib. The U-rib is welded to the body, with the outer side of the U-rib forming an outer angle with the body, and the inner side of the U-rib forming an inner angle with the body. Multiple outer welds are provided between the outer side of the U-rib and the body, and these welds are sequentially arranged along the apex of the outer angle towards the outer side. An inner corner reinforcement weld and at least one anti-penetration reinforcement weld are sequentially provided between the inner side of the U-rib and the body along the apex of the inner angle towards the inner side. It is evident that the inner corner reinforcement weld and anti-penetration reinforcement weld between the inner side of the U-rib and the body, and the multiple outer welds between the outer side of the outer U-rib and the body, changing from a single-sided fillet weld to a double-sided fillet weld, fundamentally improve the stress concentration problem at the weld root of the U-rib, thereby effectively preventing fatigue cracks from forming at the weld root, and significantly improving the fatigue strength at the weld toe of the box girder top plate.

Description

Technical Field

[0001] This application relates to the field of welding technology, and in particular to an in-service steel bridge U-rib assembly. Background Technology

[0002] Currently, such as Figure 1 As shown, the top plate 1 of the box girder and the U-rib are connected by welding. Specifically, the outer sides of the U-ribs 2 on both sides of the top plate 1 of the box girder and the U-rib are connected by welding. That is, an original external weld 7 is formed between the outer side of the U-rib and the top plate 1 of the box girder. This structure with a single external weld is prone to stress concentration. After the bridge has been in use for a period of time, weld throat cracks will appear at the weld between the U-rib and the top plate of the box girder, which poses a great safety hazard. Utility Model Content

[0003] The purpose of this application is to provide an in-service steel bridge U-rib assembly, which to some extent solves the technical problem that the top plate of the box girder is only welded to the outer side of the U-rib in the prior art. This single-sided external weld structure is prone to stress concentration, and after the bridge has been in use for a period of time, weld throat cracks will appear at the weld between the U-rib and the top plate of the box girder, which poses a great safety hazard.

[0004] This application provides an in-service steel bridge U-rib assembly, comprising: a body and a U-rib; wherein, the U-rib and the body are connected by welding, and the outer side of the U-rib forms an outer angle with the body, and the inner side of the U-rib forms an inner angle with the body; multiple outer welds are provided between the outer side of the U-rib and the body, and the multiple outer welds are sequentially arranged along the apex of the outer angle towards the outer side; an inner corner reinforcement weld and at least one anti-penetration reinforcement weld are sequentially arranged between the inner side of the U-rib and the body along the apex of the inner angle towards the inner side.

[0005] In the above technical solution, further, an inner corner reinforcement weld and an anti-penetration reinforcement weld are sequentially provided between the inner side of the U-rib and the body along the direction from the apex of the inner corner toward the inner side.

[0006] In any of the above technical solutions, further, along the extension direction of the midline of the inner corner, the height of the anti-penetration reinforcement weld is 4.5mm-6mm greater than the height of the inner corner reinforcement weld.

[0007] In any of the above technical solutions, the length of the weld leg of the inner corner reinforcement weld is 3.5mm-5mm.

[0008] In any of the above technical solutions, before forming multiple external welds between the outer side of the U-rib and the body, a preliminary weld is formed between the outer side of the U-rib and the body, and a weld throat crack is formed in the middle area of ​​the preliminary weld. After the weld throat crack is removed, a groove with an opening facing outward is formed, and multiple external welds are all set in the groove.

[0009] In any of the above technical solutions, the number of external welds is at least three.

[0010] In any of the above technical solutions, the number of external welds is three, and along the depth direction of the groove, the thickness of the first external weld is one-third of the depth of the groove, the thickness of the second external weld is one-third of the depth of the groove, and the thickness of the third external weld is 1 mm more than one-third of the depth of the groove.

[0011] In any of the above technical solutions, the groove is further defined as a U-shaped groove.

[0012] In any of the above technical solutions, the outer angle is an obtuse angle and the inner angle is an acute angle.

[0013] In any of the above technical solutions, before the inner corner welding is filled, the U-rib has a process hole, and after the inner corner welding is completed, the process hole is filled.

[0014] In any of the above technical solutions, the body is further defined as the top plate of a box girder.

[0015] Compared with the prior art, the beneficial effects of this application on the top plate of the box girder are as follows: The in-service steel bridge U-rib assembly provided in this application features internal corner reinforcement welds and anti-penetration reinforcement welds between the inner side of the U-rib and the main body, and multiple external welds between the outer side of the U-rib and the main body, changing from single-sided fillet welds to double-sided fillet welds. This fundamentally improves the stress concentration problem at the weld root of the U-rib, effectively preventing fatigue cracks from forming at the weld root, and significantly improving the fatigue strength at the weld toe of the box girder top plate. This is especially true for the in-service steel bridge U-rib assembly of this application formed using the weld throat crack repair process. First, a weld can be made between the inner side of the U-rib and the body to form an inner corner reinforcement weld. The inner corner reinforcement weld provides initial reinforcement to the original cracked area. Then, at least one anti-penetration reinforcement weld is added adjacent to the inner side of the inner corner weld. Its core function is to provide support and protection when the weld throat crack is removed by carbon arc gouging, effectively preventing the gouging through the U-rib and the body, i.e., the gouging through the base material. After the protection is completed, the weld throat crack is completely removed by precise gas gouging, and the gouging groove is filled by multi-layer and multi-pass welding process to finally form a repair weld that meets the requirements. Attached Figure Description To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the weld throat cracking that occurs on the original outer weld after the initial welding of the body and U-rib in the prior art, and after a period of use. Figure 2 This is a structural schematic diagram of an in-service steel bridge U-rib assembly provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure after welding between the body and the inner side of the U-rib in the prior art; Figure 4 This is a schematic diagram of the cracked area of ​​the weld throat of the body and U-rib in the prior art after air gouging.

[0017] Figure label: 1-Top plate of box girder, 2-U-rib, 21-Inner side, 22-Outer side, 3-Inner corner reinforcement weld, 4-Anti-penetration reinforcement weld, 5-Groogging, 6-Outer weld, 7-Original outer weld, 71-Weld throat crack, a-First direction, b-Second direction. Detailed Implementation

[0018] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0019] The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0020] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used 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. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0023] The following reference Figures 1 to 4 This application describes in-service steel bridge U-rib assemblies according to some embodiments.

[0024] See Figure 2 As shown, an embodiment of this application provides an in-service steel bridge U-rib assembly, including: a body, such as a box girder top plate 1, and a U-rib 2. It should be noted that the following description will also take the box girder top plate 1 as the body. Of course, the body is not limited to the box girder top plate 1, and can also be other structural components, depending on actual needs. The U-rib 2 is connected to the body by welding, and the outer side 22 of the U-rib 2 forms an outer angle with the body, and the inner side 21 of the U-rib 2 forms an inner angle with the body. Multiple outer welds 6 are provided between the outer side 22 of the U-rib 2 and the body, and the multiple outer welds 6 are arranged along the apex of the outer angle toward the outer side 22, that is, the first direction a. An inner angle reinforcing weld 3 and at least one anti-penetration reinforcing weld 4 are sequentially provided between the inner side 21 of the U-rib 2 and the body along the apex of the inner angle toward the outer side 22, that is, the second direction b.

[0025] As described above, in the U-rib assembly of the in-service steel bridge provided in this application, an inner corner reinforcement weld 3 and an anti-penetration reinforcement weld 4 are provided between the inner side 21 of the U-rib 2 and the main body. Multiple outer welds 6 are provided between the outer side 22 of the U-rib 2 and the main body, changing the form from a single-sided fillet weld to a double-sided fillet weld. This fundamentally improves the stress concentration problem at the weld root of the U-rib weld, thereby effectively avoiding fatigue cracks from the weld root. At the same time, it significantly improves the fatigue strength at the weld toe of the box girder top plate 1, especially when using the first process described later, namely the weld throat crack repair process. When forming the aforementioned weld structure, a corner reinforcement weld 3 can be formed by welding between the inner side 21 of the U-rib 2 and the body. The corner reinforcement weld 3 provides initial reinforcement to the original cracked area. Then, at least one anti-penetration reinforcement weld 4 is added adjacent to the inner side 21 of the corner weld. Its core function is to provide support and protection when the weld throat crack is removed by carbon arc gouging, effectively preventing the gouging through the U-rib 2 and the body, i.e., the gouging through the base material. After the protection is completed, the weld throat crack is completely removed by precise gas gouging, and the gouging groove 5 is filled by multi-layer and multi-pass welding process, finally forming a repair weld that meets the requirements.

[0026] It should be noted that the U-rib components of this in-service steel bridge can be obtained through two processes, as detailed below: The first process addresses the issue in existing technologies where the connection between the U-rib 2 and the body is solely through welding the outer side 22 of the U-rib 2 to the body. When weld throat cracks 71 appear in this structure after a period of use, the in-service steel bridge U-rib assembly's outer weld seam 6 weld throat crack repair method can be used to repair the already welded U-rib 2 and body, ultimately forming the in-service steel bridge U-rib assembly described in this embodiment. Preferably, the in-service steel bridge U-rib assembly's outer weld seam 6 weld throat crack repair method includes the following steps (see...). Figures 1 to 4 (as shown) Step 1: Drill process holes on U-rib 2; Step 2: Remove rust and clean the areas of U-rib 2 and the body to be welded (see...). Figure 1 (as shown) Step 3: Weld the inner side 21 of U-rib 2 to the body to form an inner corner reinforcement weld 3 (see...) Figure 3 (as shown) Step 4: Along the extension direction of the centerline of the second corner formed by the inner side 21 of U-rib 2 and the body, sequentially weld at least one anti-penetration reinforcing weld 4 on the inner side 21 of the inner corner reinforcement weld 3 (see...). Figure 3 (as shown) Step 5: Perform air gouging on the weld throat cracked area of ​​the original outer weld 7 formed between the body and the outer side 22 of U-rib 2 to remove the crack and its extension at the weld throat until defect-free metal is exposed (see...). Figure 4(as shown); further, preferably, the groove 5 is a U-shaped groove, that is, a U-shaped bevel, which has a regular shape and is easy to fill. Preferably, the length of the U-shaped bevel extends 30mm to 40mm beyond both ends of the weld throat crack 71, and the slope ratio of the two ends of the U-shaped bevel is 1:6 to 1:8. Of course, the structure of the groove 5 is not limited to this and can be selected according to actual needs. Step Six: Clean the gouging groove 5 formed by air gouging, removing slag and oxide scale. Then, along the extension direction of the centerline of the first angle formed by the outer side 22 of U-rib 2 and the body, gradually fill the gouging groove 5 using a multi-layer, multi-pass welding process to form multiple outer welds 6 (see...). Figure 2 (As shown). It should be noted that the above steps are just a simple illustration, and there are other detailed steps, which will not be described in detail here.

[0027] The second process is designed for the initial state where the U-rib 2 and the body are two independent structural components that are not welded together. Preferably, the manufacturing process of the in-service steel bridge U-rib assembly includes the following steps: Step 1: Drill process holes on U-rib 2; Step 2: Remove rust and clean dirt from U-rib 2 and the parts of the body to be welded; Step 3: Assemble and position U-rib 2 with the body, then spot weld the outer side 22 of U-rib 2 to the body, and then weld the inner side 21 of U-rib 2 to the body to form an inner corner reinforcement weld 3. Step 4: Along the extension direction of the midline of the inner angle formed by the inner side 21 of U-rib 2 and the body, at least one anti-penetration reinforcing weld 4 is sequentially welded on the inner side 21 of the inner angle reinforcement weld 3. Step 5: Along the extension direction of the center line of the outer corner formed by the outer side 22 of U rib 2 and the body, the groove 5 is gradually filled with a multi-layer, multi-pass welding process to form multiple outer welds 6. Both of the above processes can be used to obtain the in-service steel bridge U-rib assembly in this embodiment. That is, the in-service steel bridge U-rib assembly is obtained by repairing the initial welding position of the U-rib and the body using the first process, and the in-service steel bridge U-rib assembly can be directly assembled and manufactured using the second process. It can be seen that the above two processes can be selected according to actual needs to obtain the in-service steel bridge U-rib assembly in this embodiment.

[0028] In this embodiment, preferably, as follows: Figure 2 As shown, an inner corner reinforcement weld 3 and an anti-penetration reinforcement weld 4 are sequentially provided between the inner side 21 of U rib 2 and the body along the direction from the apex of the inner corner toward the outer side 22. As can be seen from the structure described above, an inner corner reinforcement weld 3 can play a preliminary reinforcement role, and an anti-penetration reinforcement weld 4 can play a secondary reinforcement role. Moreover, the two welds change the stress concentration position generated by the outer weld 6, moving the stress concentration position from the original root area of ​​U rib 2 to the outer side 22 at a certain distance from the root, so that cracking will no longer occur in the root area of ​​U rib 2.

[0029] It should be noted that, especially for the first process mentioned above, the internal corner reinforcement weld 3 and the anti-penetration reinforcement weld 4 also have other functions. That is to say, by setting up an internal corner reinforcement weld 3, the original cracked area can be initially reinforced. Adjacent to the internal corner reinforcement weld 3, only one anti-penetration reinforcement weld 4 needs to be added to provide support and protection when the weld throat crack is removed by carbon arc gouging. Moreover, the operation is simple, the work efficiency is high, and welding materials are saved.

[0030] Furthermore, it should be noted that the structure is not limited to the above-mentioned structure of adding only one anti-penetration reinforcing weld 4 to the inner side 21 of the inner corner reinforcement weld 3. Multiple anti-penetration reinforcing welds 4 can also be added sequentially along the extension direction of the center line of the inner corner to the inner side 21 of the inner corner reinforcement weld 3. The specific choice depends on the actual needs.

[0031] In this embodiment, preferably, as follows: Figure 2 As shown, along the extension direction of the midline of the inner corner, the height of the anti-penetration reinforcing weld 4 is 4.5mm-6mm greater than the height of the inner corner reinforcing weld 3. That is to say, the height of the anti-penetration reinforcing weld 4 is H, the height of the inner corner reinforcing weld 3 is h, and Δh=Hh, and 4.5mm≤Δh≤6mm. Based on the structure described above, if Δh is too small, it will not provide good support and protection when removing weld throat cracks in the subsequent carbon arc gouging. If Δh is too large, it will waste time and materials. Therefore, Δh is set within the range of 4.5mm-6mm to provide effective support and protection when removing weld throat cracks in the subsequent carbon arc gouging.

[0032] In this embodiment, preferably, as follows: Figure 2 As shown, the length of the weld leg of the inner corner reinforcement weld 3 is L, and 3.5mm≤L≤5mm. Based on the structure described above, it can be seen that if the length of the weld leg of the inner corner reinforcement weld 3 is too small, it cannot play a preliminary reinforcement role for the original cracked area. If the length of the weld leg of the inner corner reinforcement weld 3 is too large, it will increase the welding difficulty and waste materials. Therefore, the length of the weld leg of the corner reinforcement weld should be taken in the range of 3.5mm-5mm, which can satisfy the preliminary reinforcement role without increasing the welding difficulty and wasting materials.

[0033] In this embodiment, preferably, as follows: Figures 2 to 4As shown, before multiple external welds 6 are formed between the outer side 22 of U-rib 2 and the body, an early weld is formed between the outer side 22 of U-rib 2 and the body, and a weld throat crack 71 is formed in the middle area of ​​the early weld. After the weld throat crack 71 is removed, a groove 5 with an opening facing the outer side 22 is formed, and multiple external welds 6 are all set in the groove 5.

[0034] Based on the structure described above, it can be seen that the weld throat crack 71 can be removed by air gouging or other methods, that is, a gouging groove 5 can be formed, and then the outer weld 6 can be welded in the gouging groove 5, thereby repairing the weld throat crack.

[0035] In this embodiment, preferably, as follows: Figure 2 As shown, the number of outer welds 6 is three, which can meet the connection requirements and strength requirements, and can effectively reduce the energy input of the welding line and ensure the quality of welding. Of course, it is not limited to this. The number of outer welds 6 can be more than three or less than three, depending on the actual needs. In this embodiment, preferably, as follows: Figure 2 and Figure 4 As shown, there are three outer welds 6. Along the depth direction of the groove 5, the thickness c1 of the first outer weld 6 is one-third of the depth L of the groove 5, the thickness c2 of the second outer weld 6 is one-third of the depth L of the groove 5, and the thickness c3 of the third outer weld 6 is 1mm more than one-third of the depth L of the groove 5.

[0036] Based on the structure described above, the first weld fills one-third of the groove 5, providing sufficient thickness to meet the requirements and preventing burn-through during the second weld. The second weld also fills one-third of the groove 5, effectively reinforcing the first weld. The third weld fills the remaining one-third of the groove 5 and extends 1mm above the groove opening, ensuring complete filling of the entire groove 5. This serves as the final sealing weld, making the outer weld 6 more robust overall. Therefore, welding three outer welds 6 in three stages according to the above data effectively reduces the energy input to the welding line and ensures weld quality. In this embodiment, preferably, as follows: Figure 4 As shown, the groove 5 is a U-shaped groove, which can completely remove the weld throat crack 71 in the middle area, and its regular shape facilitates subsequent welding operations. Of course, the shape of the groove 5 is not limited to this and can be selected according to actual needs.

[0037] In this embodiment, preferably, as follows: Figure 2 As shown, the outer angle is obtuse and the inner angle is acute, which meets the actual use requirements. Of course, it is not limited to this. The outer side 22 of U rib 2 forms an acute angle with the body, and the inner side 21 of U rib 2 forms an obtuse angle with the body, etc. In this embodiment, preferably, before the inner corner welding is filled, the U-rib 2 has a process hole, and after the inner corner welding is completed, the process hole is filled, which facilitates the insertion of automatic welding equipment into the U-rib 2 for welding. Moreover, after the welding is completed, the process hole is filled to ensure strength.

[0038] In this embodiment, preferably, the body is the top plate 1 of the box girder. During assembly, the opening of the U-rib faces the top plate 1 of the box girder. After assembly, both side plates of the U-rib need to be welded to the top plate 1 of the box girder. Of course, it is not limited to this; the structure of the body can be selected according to actual needs. Furthermore, the body is not limited to the top plate 1 of the box girder; it can be other structures. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A U-rib assembly for in-service steel bridges, characterized in that, include: The body and the U-rib; wherein the U-rib is connected to the body by welding, and the outer side of the U-rib forms an outer angle with the body, and the inner side of the U-rib forms an inner angle with the body; multiple outer welds are provided between the outer side of the U-rib and the body, and the multiple outer welds are arranged sequentially along the apex of the outer angle towards the outer side; an inner corner reinforcement weld and at least one anti-penetration reinforcement weld are arranged sequentially between the inner side of the U-rib and the body along the apex of the inner angle towards the inner side.

2. The in-service steel bridge U-rib assembly according to claim 1, characterized in that, Between the inner side of the U-rib and the body, a corner reinforcement weld and a penetration-resistant reinforcement weld are sequentially arranged along the apex of the inner corner towards the inner side.

3. The in-service steel bridge U-rib assembly according to claim 2, characterized in that, Along the extension direction of the midline of the inner corner, the height of the anti-penetration reinforcement weld is 4.5mm-6mm greater than the height of the inner corner reinforcement weld.

4. The in-service steel bridge U-rib assembly according to claim 1, characterized in that, The length of the weld leg of the internal corner reinforcement weld is 3.5mm-5mm.

5. The in-service steel bridge U-rib assembly according to claim 1, characterized in that, Before multiple external welds are formed between the outer side of the U-rib and the body, a preliminary weld is formed between the outer side of the U-rib and the body, and a weld throat crack is formed in the middle area of ​​the preliminary weld. After the weld throat crack is removed, a groove with an opening facing outward is formed, and multiple external welds are all set in the groove.

6. The in-service steel bridge U-rib assembly according to claim 5, characterized in that, The number of external welds is at least three.

7. The in-service steel bridge U-rib assembly according to claim 6, characterized in that, The number of external welds is three, and along the depth direction of the groove, the thickness of the first external weld is one-third of the depth of the groove, the thickness of the second external weld is one-third of the depth of the groove, and the thickness of the third external weld is 1 mm more than one-third of the depth of the groove.

8. The in-service steel bridge U-rib assembly according to claim 5, characterized in that, The groove is a U-shaped groove.

9. The in-service steel bridge U-rib assembly according to claim 1, characterized in that, The outer angle is an obtuse angle, and the inner angle is an acute angle.

10. The in-service steel bridge U-rib assembly according to any one of claims 1 to 9, characterized in that, Before the inner corner welds are filled, the U-rib has process holes formed, and after the inner corner welds are completed, the process holes are filled; and / or The main body is the top plate of the box girder.

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