Large-span steel box girder residual stress detection method, device, equipment and medium

Abstract

The invention discloses a method, a device, equipment and a medium for detecting residual stress of a large-span steel box girder, and the method comprises the steps: screening a current analysis region from a plurality of to-be-analyzed plate surfaces in a large-span steel box girder model, setting three analysis paths which are distributed at intervals in the current analysis region, carrying out the data collection of the three analysis paths, and obtaining the residual stress of the large-span steel box girder; analyzing the equivalent residual stress field to obtain equivalent stress data information corresponding to each analysis path, and analyzing the equivalent stress data information corresponding to each analysis path along the extension direction of the welding seam according to influence parameters of each analysis path on the corresponding equivalent residual stress field to obtain equivalent stress data information corresponding to each analysis path. According to the method, the residual stress distribution rule of the large-span steel box girder can be accurately analyzed, the influence result of each influence parameter on the residual stress of the large-span steel box girder can also be obtained, and a guarantee is provided for determining the influence reason of the residual stress of the large-span steel box girder.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a method, device, equipment and medium for detecting residual stress of a large-span steel box girder. Background Art

[0002] The beams of bridge projects are usually constructed by on-site casting or prefabrication. The beams mainly include steel box beams and concrete beams. Steel box beams are widely used in the jacking process due to their light weight and good performance. In the process of construction using prefabrication and assembly, the jacking method is a new assembly technology. The specific process of the jacking method is: set up a construction site on land in the area where the bridge head is located, manufacture the beams in the construction site, and after the beams are manufactured, use jacks and other jacking mechanisms to push the beams onto the piers to complete the beam assembly construction.

[0003] During the welding process of the steel box girder, after the welding is completed, the residual stress will cause the steel box girder to deform or stress concentration and damage. In the prior art, when detecting the residual stress, it is usually detected by knocking and other methods. When using these methods for detection, there is a risk of damaging the welded steel box girder. Summary of the invention

[0004] The main purpose of the present invention is to provide a method, device, equipment and medium for detecting residual stress of a large-span steel box girder, aiming to solve the technical problem that in the related art, when detecting residual stress, it is usually detected by knocking and the like. When using these methods for detection, there is a risk of damaging the welded steel box girder.

[0005] To achieve the above object, in a first aspect, the present invention provides a method for detecting residual stress of a long-span steel box girder, wherein a welding area is formed on the long-span steel box girder, and a weld is formed in the welding area;

[0006] The method for detecting residual stress of a large-span steel box girder comprises the following steps:

[0007] A plurality of detection positions are arranged on the large-span steel box girder and are distributed in the welding area at intervals along the circumferential direction; wherein the plurality of detection positions are paired in pairs and are relatively distributed on both sides of the weld;

[0008] Performing real-time ultrasonic testing on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions;

[0009] Making the real-time residual stress data corresponding to each of the detection positions into a line graph;

[0010] The line graphs are analyzed in sequence to obtain residual stress detection results of the welding area corresponding to each detection position.

[0011] Optionally, the step of setting a plurality of detection positions on the long-span steel box girder and distributed circumferentially at intervals in the welding area comprises:

[0012] A plurality of detection positions are arranged on the long-span steel box girder, which are circumferentially spaced apart in the welding area and are at a target distance from the weld.

[0013] Optionally, the target distance is A, where 2cm≤A≤6cm.

[0014] Optionally, the center distance between any two adjacent welding positions located on the same side of the weld is B, where 20 cm ≤ 60 cm.

[0015] Optionally, the step of sequentially performing real-time ultrasonic testing on each of the detection positions to obtain real-time residual stress data corresponding to each of the detection positions includes:

[0016] Performing grinding construction on each of the detection positions in turn;

[0017] An ultrasonic testing instrument is installed at each of the testing positions after the grinding construction is completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions.

[0018] Optionally, the step of installing an ultrasonic testing instrument at each of the testing positions after the grinding construction has been completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions includes:

[0019] After the grinding construction is completed, a coupling agent is applied to each of the detection positions and an ultrasonic detection instrument is installed to perform real-time ultrasonic detection to obtain real-time residual stress data corresponding to each of the detection positions.

[0020] Based on the same technical concept, in a second aspect, the present invention proposes a residual stress detection device for a large-span steel box girder, comprising:

[0021] A detection position determination module, used for setting a plurality of detection positions on the long-span steel box girder and distributed in the welding area at intervals along the circumferential direction;

[0022] An ultrasonic detection module, used to perform real-time ultrasonic detection on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions;

[0023] A graphing module, used for making the real-time residual stress data corresponding to each of the detection positions into a line graph;

[0024] The result acquisition module is used to analyze the line graph in sequence to obtain the residual stress detection result of the welding area corresponding to each detection position.

[0025] Based on the same technical concept, in a third aspect, the present invention proposes a residual stress detection system for a large-span steel box girder, comprising:

[0026] Ultrasonic testing equipment; and,

[0027] A residual stress detection device is communicatively connected to the ultrasonic detection instrument to implement the residual stress detection method for a large-span steel box girder described in the first aspect.

[0028] Based on the same technical concept, in the fourth aspect, the present invention proposes a large-span steel box girder residual stress detection device, the large-span steel box girder residual stress detection device includes a processor and a memory, the memory stores a large-span steel box girder residual stress detection program, and when the large-span steel box girder residual stress detection program is executed by the processor, the large-span steel box girder residual stress detection method described in the first aspect is implemented.

[0029] Based on the same technical concept, in the fifth aspect, the present invention proposes a computer storage medium, on which a computer program is stored. When the computer program is executed by one or more processors, the method for detecting residual stress of a large-span steel box girder described in the first aspect is implemented.

[0030] The technical solution of the present invention is to set a plurality of detection positions on a large-span steel box girder and distribute them in the welding area at intervals along the circumferential direction, perform real-time ultrasonic detection on each detection position in turn to obtain real-time residual stress data corresponding to each detection position, make the real-time residual stress data corresponding to each detection position into a line graph, analyze the line graph in turn to obtain the residual stress detection result of the welding area corresponding to each detection position, so that when the present invention is used, there is no need to perform operations such as knocking on the detection position that may cause damage to the detection position, thereby avoiding damage to the steel box girder and realizing non-destructive detection of the steel box girder. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0032] Figure 1 A flow chart of a method for detecting residual stress of a large-span steel box girder according to an example of the present invention;

[0033] Figure 2 for Figure 1 Flow chart of step S200 in the example;

[0034] Figure 3 This is a schematic diagram of the U-rib detection position arrangement of an example of the present invention;

[0035] Figure 4 It is a schematic diagram of the arrangement of the web plate detection positions according to an example of the present invention;

[0036] Figure 5 for Figure 4 The detection result diagram of the left detection position in the example;

[0037] Figure 6 for Figure 4 The detection result diagram of the right detection position in the example;

[0038] Figure 7 It is a schematic diagram of the detection position arrangement of the first web in the factory state of an example of the present invention;

[0039] Figure 8 for Figure 7 The detection result diagram of the left detection position in the example;

[0040] Fig. 9 for Figure 7 The detection result diagram of the right detection position in the example;

[0041] Fig.10 It is a schematic diagram of the detection position arrangement of the third web in the factory state of an example of the present invention;

[0042] Fig.11 for Fig.10 The detection result diagram of the left detection position in the example;

[0043] Fig.12 for Fig.10 The detection result diagram of the right detection position in the example;

[0044] Fig.13 It is a schematic diagram of the detection position arrangement of the first partition in the factory state of an example of the present invention;

[0045] Fig.14 for Fig.13 The pre-weld inspection result diagram of the left inspection position in the example;

[0046] Fig.15 for Fig.13 The pre-weld inspection result diagram of the right inspection position in the example;

[0047] Fig.16 for Fig.13The post-weld inspection result diagram of the left inspection position in the example;

[0048] Fig.17 for Fig.13 The post-weld inspection result diagram of the right inspection position in the example;

[0049] Fig.18 A schematic diagram of the detection position arrangement of the second partition in a factory state of an example of the present invention;

[0050] Fig.19 for Fig.18 The pre-weld inspection result diagram of the left inspection position in the example;

[0051] Fig. 20 for Fig.18 The pre-weld inspection result diagram of the right inspection position in the example;

[0052] Fig.21 for Fig.18 The post-weld inspection result diagram of the left inspection position in the example;

[0053] Fig. 22 for Fig.18 The post-weld inspection result diagram of the right inspection position in the example;

[0054] Fig.23 It is a schematic diagram of the detection position arrangement of the first top plate in the factory state of an example of the present invention;

[0055] Fig.24 for Fig.23 The detection result diagram of the detection position on the A side of the example;

[0056] Fig.25 for Fig.23 The detection result diagram of the detection position on the B side of the example;

[0057] Fig.26 A schematic diagram of the detection position arrangement of the second top plate in the factory state of an example of the present invention;

[0058] Fig. 27 for Fig.26 The detection result diagram of the detection position on the A side of the example;

[0059] Fig.28 for Fig.26 The detection result diagram of the detection position on the B side of the example;

[0060] Fig.29 This is a temperature monitoring result diagram of an example of the present invention;

[0061] Fig.30 It is a schematic diagram of the detection position arrangement of the first welding plate of the present invention;

[0062] Figure 31(a) shows Fig.30 The stress detection result diagram of the first welding plate at positions 3-1, 3-3, 3-5, and 3-7 perpendicular to the weld direction in the example; Figure 31(b) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-2, 3-4, 3-6, and 3-8 perpendicular to the weld direction in the example; Figure 31(c) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-9, 3-11, 3-14, and 3-15 perpendicular to the weld direction in the example; Figure 31(d) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-10, 3-12, 3-14, and 3-16 perpendicular to the weld direction in the example;

[0063] Figure 32(a) shows Fig.30 The stress detection result diagram of the first welding plate at positions 3-1 and 3-9 parallel to the weld direction in the example; Figure 32(b) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-3 and 3-11 parallel to the weld direction in the example; Figure 32(c) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-2 and 3-10 parallel to the weld direction in the example; Figure 32(d) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-4 and 3-12 parallel to the weld direction in the example;

[0064] Fig.33 It is a schematic diagram of the detection position arrangement of the second welding plate of the present invention;

[0065] Figure 34(a) shows Fig.30 The stress detection result diagram of the first welding plate at positions 3-1, 3-3, 3-5, and 3-7 perpendicular to the weld direction in the example; Figure 34(b) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-2, 3-4, 3-6, and 3-8 perpendicular to the weld direction in the example; Figure 34(c) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-9, 3-11, 3-14, and 3-15 perpendicular to the weld direction in the example; Figure 34(d) is Fig.30 The stress detection result diagram of the first welding plate at positions 3-10, 3-12, 3-14, and 3-16 perpendicular to the weld direction in the example;

[0066] Figure 35(a) shows Fig.30 The stress detection result diagram of the 0-11 and 3-11 positions of the first welding plate in the example is parallel to the weld direction; Figure 35(b) is Fig.30 The stress detection result diagram of the 0-13 and 3-13 positions of the first welding plate in the example is parallel to the weld direction; Figure 35(c) is Fig.30The stress detection result diagram of the 0-12 and 3-12 positions of the first welding plate in the example is parallel to the weld direction; Figure 35(d) is Fig.30 The stress detection result diagram of the first welding plate at positions 0-14 and 3-14 parallel to the weld direction in the example;

[0067] Fig.36 This is a structural diagram of a residual stress detection device for a large-span steel box girder according to an example of the present invention.

[0068] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0069] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0070] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between various mechanisms under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0071] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0072] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0073] The inventive concept of the present invention is further described below in conjunction with some specific implementation methods.

[0074] See also Figures 1 to 36 The present invention proposes some embodiments of a method, device, equipment and medium for detecting residual stress of a large-span steel box girder.

[0075] See also Figures 1 to 36 , the residual stress detection method of the large-span steel box girder, a welding area is formed on the large-span steel box girder, and a weld is formed in the welding area;

[0076] The method for detecting residual stress of a large-span steel box girder comprises the following steps:

[0077] S100, setting a plurality of detection positions on the long-span steel box girder and distributed in the welding area at intervals along the circumferential direction; wherein the plurality of detection positions are paired in pairs and relatively distributed on both sides of the weld;

[0078] S200, performing real-time ultrasonic testing on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions;

[0079] S300, making the real-time residual stress data corresponding to each detection position into a line graph;

[0080] S400, analyzing the line graph in sequence to obtain residual stress detection results of the welding area corresponding to each detection position.

[0081] In this embodiment, a plurality of detection positions are set on the large-span steel box girder and are distributed in the welding area along the circumferential direction at intervals. Real-time ultrasonic detection is performed on each detection position in turn to obtain real-time residual stress data corresponding to each detection position. The real-time residual stress data corresponding to each detection position is made into a line graph, and the line graph is analyzed in turn to obtain the residual stress detection results of the welding area corresponding to each detection position. When the present invention is used, there is no need to perform operations such as knocking on the detection position that may cause damage to the detection position, thereby avoiding damage to the steel box girder and realizing non-destructive detection of the steel box girder.

[0082] In some specific embodiments, step S100 includes:

[0083] A plurality of detection positions are arranged on the long-span steel box girder, which are circumferentially spaced apart in the welding area and are at a target distance from the weld.

[0084] Exemplarily, the target distance is A, where 2 cm ≤ A ≤ 6 cm. The center distance between any two adjacent welding positions on the same side of the weld is B, where 20 cm ≤ 60 cm.

[0085] In some specific embodiments, step S200 includes:

[0086] S210, performing grinding construction on each of the detection positions in sequence;

[0087] S220, installing an ultrasonic testing instrument at each of the testing positions after the grinding construction is completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions.

[0088] Preferably, the step of installing an ultrasonic testing instrument at each of the testing positions after the grinding construction has been completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions includes:

[0089] After the grinding construction is completed, a coupling agent is applied to each of the detection positions and an ultrasonic detection instrument is installed to perform real-time ultrasonic detection to obtain real-time residual stress data corresponding to each of the detection positions.

[0090] In an exemplary embodiment, an ultrasonic method for detecting residual stress is used in the actual residual stress detection process. Theoretical studies have shown that the propagation speed of elastic waves in stressed solid materials depends not only on the second-order elastic constant, higher-order elastic constant and density of the material, but also on the residual stress, which is manifested as an acoustic elastic effect. Compressive or tensile residual stress will affect the propagation speed of ultrasonic waves. When the stress on a component is within the yield strength, it is an elastic deformation. At this time, the speed of sound is proportional to the stress. When there is tensile stress in the component, the speed of sound can be reduced. When there is compressive stress in the component, the speed of sound can be accelerated. Therefore, it is completely desirable to use ultrasonic waves to detect residual stress in actual operation.

[0091] in, Fig.31a The broken lines 3-1, 3-3, 3-5, and 3-7 in the example are stress detection result diagrams of points 3-1, 3-3, 3-5, and 3-7 of the first weld plate perpendicular to the weld direction; Fig.31b The broken lines 3-2, 3-4, 3-6, and 3-8 in the example are stress detection result diagrams of points 3-2, 3-4, 3-6, and 3-8 of the first weld plate perpendicular to the weld direction;

[0092] Fig.31c The broken lines 3-9, 3-11, 3-13, and 3-15 in the example are stress detection result diagrams of points 3-9, 3-11, 3-13, and 3-15 of the first weld plate perpendicular to the direction of the weld; Fig.31d The broken lines 3-10, 3-12, 3-14, and 3-16 in the example are stress detection result diagrams of points 3-10, 3-12, 3-14, and 3-16 of the first weld plate perpendicular to the direction of the weld;

[0093] Fig.32a The broken lines 3-1 and 3-9 in the example are stress detection result diagrams of points 3-1 and 3-9 of the first weld plate parallel to the weld direction; Figure 32b The broken lines 3-3 and 3-11 in the example are stress detection result diagrams of points 3-3 and 3-11 of the first weld plate parallel to the weld direction; Fig.32c The broken lines 3-2 and 3-10 in the example are stress detection result diagrams of points 3-2 and 3-10 of the first weld plate parallel to the weld direction; Fig.32d The broken lines 3-4 and 3-12 in the example are stress detection result diagrams of points 3-4 and 3-12 of the first weld plate parallel to the weld direction; Fig.34a The broken lines 3-1, 3-5, 3-7, and 3-3 in the example are stress detection result diagrams of points 3-1, 3-5, 3-7, and 3-3 of the second welding plate perpendicular to the direction of the weld; Fig.34b The broken lines 3-2, 3-4, 3-6, and 3-8 in the example are stress detection result diagrams of points 3-2, 3-4, 3-6, and 3-8 of the second welding plate perpendicular to the direction of the weld; Fig.34cThe broken lines 3-9, 3-11, 3-13, and 3-15 in the example are stress detection result diagrams of points 3-9, 3-11, 3-13, and 3-15 of the second welding plate perpendicular to the direction of the weld; Fig.34d The broken lines 3-10, 3-12, 3-14, and 3-16 in the example are stress detection result diagrams of points 3-10, 3-12, 3-14, and 3-16 of the second welding plate perpendicular to the direction of the weld; Fig.35a The 0-11 and 3-11 broken lines in the example are stress detection result diagrams of the second weld plate points 0-11 and 3-11 parallel to the weld direction; Fig.35b The 0-13 and 3-13 broken lines in the example are stress detection result diagrams of the second weld plate points 0-13 and 3-13 parallel to the weld direction; Fig.35c The 0-12 and 3-12 broken lines in the example are stress detection result diagrams of the second weld plate points 0-12 and 3-12 parallel to the weld direction; Fig.35d The 0-14 and 3-14 broken lines in the example are stress detection result diagrams of points 0-14 and 3-14 of the second welding plate parallel to the weld direction.

[0094] The instruments used in the detection process include: ultrasonic probes, signal converters, ultrasonic detection systems, etc. During the detection, the surface of the detection object needs to be cleaned and polished first to ensure the smoothness of the plane to reduce errors in the detection process. After polishing, evenly apply coupling agent on both ends of the probe, and then start the detection.

[0095] In the on-site measurement, a U-rib was selected for detection using ultrasonic equipment. The detection position is shown in the figure below. Points 1-6 are all about 3 cm away from the U-rib weld, and the detection direction is perpendicular to the weld direction. During the detection, the U-rib detection position was first polished, and then the coupling agent was evenly applied after polishing, and then the detection was performed. The detection results are shown in Table 1 below.

[0096] Table 1: U-rib measured data

[0097]

[0098] As can be seen from Table 1 above, after the U-rib welding is completed, there will be residual stress on the partition, and its size and distribution are not particularly obvious. The change of stress during welding is very complicated. For this reason, this research group also conducted field inspections on the welding of the web. The points are 1-4 from top to bottom. The upper and lower test points are about 40cm apart, and the test position is about 2cm away from the weld. During the inspection, the web test position is first polished, and then the coupling agent is evenly applied after polishing, and then the inspection is carried out. The results are shown in Table 2 below.

[0099] Table 2: Measured data of web:

[0100] Left point 1 2 3 4 Measured data (unit: MPa) 86.02 216.35 -260.67 -62.56 Right point 1 2 3 4 Measured data (unit: MPa) 33.89 263.27 -161.61 -2.61

[0101] For ease of display, the data table is converted into an image.

[0102] The stress distribution on the left and right sides of the web weld is relatively symmetrical, with larger residual stress in the middle and smaller residual stress at the upper and lower ends. The reason is not only related to the structural change of the steel after melting during the welding process, but also there are other welds around the web position, which will also lead to uneven changes in residual stress around the web weld. Combining the residual stress around the U-rib and web weld, it can be seen that residual stress will remain after the steel is welded, and it needs to be reduced to a certain extent when the residual stress is too large. Subsequently, in order to compare the difference between the on-site welding process and the factory welding process, two webs were selected in the factory for testing.

[0103] Since there are other welds on the B side of the weld, the residual stresses on both sides of the weld are not symmetrically distributed, and the tensile stress on the B side is generally higher than the stress on the A side. Therefore, it can be inferred that due to the existence of other welds around the measured weld, the stresses around the two welds will affect each other, resulting in an increase in compressive stress or tensile stress.

[0104] During the on-site inspection, several other welding positions were also inspected, among which two partitions were inspected first. Before the welds were welded, ten points were selected on each partition for inspection.

[0105] After welding was completed, the same location was inspected again.

[0106] The welding residual stress on the left and right sides of the weld is symmetrical in positive and negative directions, and slightly asymmetrical in stress magnitude, which may be due to the error caused by the surface grinding of the measuring point not being smooth enough during the detection process. In the stress diagram before and after welding, it can be seen that after welding, the compressive stress on both sides of the weld begins to weaken, and the tensile stress increases. It can be judged that during the steel welding process, the internal tensile stress of the material on both sides of the weld is increased through the process of hot melting and combining the two sides.

[0107] In addition to the inspection at the partition, two top plates were also selected for stress testing.

[0108] Since the on-site grinding effect is somewhat rough, and the ultrasonic testing conditions require a relatively smooth surface, it can be seen from the test results that the test results are not only asymmetrical on both sides, but also the stress distribution trend on both sides is somewhat messy.

[0109] In order to explore the actual distribution of welding residual stress, this research group selected two steel plates for welding measurement. The steel plate material is Q345 steel, with a length of 600mm, a width of 500mm, and a thickness of 16mm. The welding direction is along the long side. Strain gauges are used for detection at the measuring points. Two strain gauges are placed at each measuring point to detect the stress in the directions perpendicular to the weld and parallel to the weld respectively. The data is collected using a static strain gauge. In order to clearly distinguish the data of each measuring point, each strain gauge is numbered. Among them, the even number is the strain gauge data parallel to the weld direction, and the odd number is the strain gauge data perpendicular to the weld direction. When detecting welding stress, a group of temperature sensors are arranged at the same time to detect the welding temperature. The measuring points are A, B, C, and D from near to far from the weld.

[0110] During welding, the temperature around the weld increases rapidly, and the temperature decreases with the distance from the weld, and the overall temperature distribution is relatively uniform.

[0111] Strain gauges are installed when welding steel plates to detect stress changes during the welding process.

[0112] The ones with odd digits at the end detect the stress perpendicular to the weld direction, while the ones with even digits at the end detect the stress parallel to the weld direction.

[0113] The same group and the same direction are just different in distance from the measuring point to the weld. It can be seen from the figure that when the steel plate is welded, the stress change trend, whether perpendicular to the weld direction or parallel to the weld direction, is that the closer to the weld, the greater the stress change. The maximum stress perpendicular to the weld direction exceeds 1000MPa. At this time, the stress has long exceeded the elastic strain value of the Q345 steel plate. Therefore, it can be inferred that the elasticity of the steel plate near the weld has changed.

[0114] At the same distance from the weld, the stress changes in the same direction are roughly consistent, so it can be inferred that the distance from the measuring point to the weld is the main influencing factor of the residual stress of steel plate welding, and the closer the distance to the weld, the greater the impact.

[0115] In order to ensure the accuracy of the test, another set of steel plates was used to arrange the measuring points.

[0116] Its changing pattern is the same as that of the first welding plate. The stress changes significantly at positions close to the welding plate, especially the stress change perpendicular to the weld direction is more drastic than the stress change trend parallel to the weld direction. This shows that attention should be paid to the residual stress perpendicular to the weld direction during the welding process. If conditions permit, the residual stress should be reduced after welding is completed to ensure the stability of the overall structure during later operation.

[0117] In order to reduce the impact of the equipment on the data, another data acquisition instrument of the same model was used for testing. The data collected by the new data acquisition instrument were numbered from 0-9 to 0-16. The detection direction numbering pattern was the same as that of the first data acquisition instrument. The odd numbers at the end of the numbers detected the stress perpendicular to the weld direction, and the even numbers at the end of the numbers detected the stress parallel to the weld direction. A part of the welding process was selected for data comparison.

[0118] Whether it is perpendicular to the weld direction or parallel to the weld direction, the stress transformation trend is approximately the same, and the numerical change is not very obvious. Therefore, it can be inferred that different data acquisition equipment may have some impact on the data, but the impact is not significant.

[0119] There are many methods for reducing residual stress at present. The traditional reduction methods include natural aging, heat treatment and impact vibration. However, with the emergence of emerging technologies, new reduction methods have gradually begun to be applied in engineering practice. Among them, the development of high-energy ultrasonic technology has provided new ideas for residual stress reduction.

[0120] The basic principle of high-energy ultrasound to eliminate residual stress is that the high-energy ultrasound amplitude fluctuates greatly, causing the grains or lattices in the area where the residual stress exceeds the standard to produce alternating vibration or creep, and inducing a series of secondary effects such as ultrasonic softening and dislocation movement; in addition, the high-energy sound field will also produce periodic or intermittent shock waves, forming a local pressure gradient at the wave front, thereby causing local heating of the grain boundary, accelerating the softening of the material, promoting slip between grains, and ultimately eliminating residual stress.

[0121] This technology has the advantages of good stress elimination effect, low cost, low energy consumption, high speed, easy to use in the field of mechanical workpiece service, and can achieve local focus control on site. According to the test data, the overall elimination rate of welding residual stress by high-energy ultrasonic method is between 24.52% and 37.23%, and more significant elimination effect is observed in areas with higher initial residual stress levels.

[0122] Since this project uses a large number of steel box girders with a complex structure, the steel box girders are manufactured in a specific factory and then transported to the site for assembly through the correct transportation methods and routes. After assembly, jacking construction and subsequent work are carried out. Therefore, when manufacturing steel box girders in the factory, special attention should be paid to the residual stress generated by each plate during welding, because the instability of residual stress may cause many adverse effects on the subsequent use of the bridge.

[0123] When controlling the welding deformation and internal stress release of steel box girders, we must first strictly follow the welding process requirements of first assembling and welding correction of individual components and then welding correction of the final assembly.

[0124] Bridge welding needs to be supported by qualified welding process assessment. Before welding of single components and assembly, a reasonable welding process must be formulated according to the welding method, welding position, part material, plate thickness, joint form, etc. When conditions permit or it is easy to flip, try to avoid overhead welding, and reasonably adopt vertical welding, and mostly adopt horizontal and transverse welding. For joints with full penetration or partial penetration welding with a large amount of welding, it is advisable to weld both sides alternately, and increase the number of alternations as much as possible; when double-sided symmetrical welding is not possible, it is advisable to use a small current, high welding speed and multiple passes to complete the welding while ensuring the quality of the weld. Long welds with a large amount of welding should be welded in sections.

[0125] When welding on the same component, the heat should be dispersed and symmetrically distributed as much as possible. For example, for the longitudinal stiffening ribs of the wall panel, the stiffening ribs at the edge of the wall panel can be welded first, and then the stiffening ribs in the middle. Reasonably control the interlayer temperature. Too high an interlayer temperature is more likely to cause greater welding deformation of the component.

[0126] Long welds of important components can be welded by segmented back-welding or multi-person symmetrical welding to avoid local heat concentration on the workpiece and large deformation. For joints with large shrinkage or angular deformation, reserved welding shrinkage allowance or anti-deformation method should be used to control shrinkage and deformation before formal welding.

[0127] When welding, use necessary assembly and welding frames, tooling fixtures, process partitions and support rods. All assembly fixtures that control deformation should be removed after the weld has completely cooled to room temperature and should not be removed in advance.

[0128] The positions that are still deformed after welding can be corrected by flame correction to ensure that the size of the components meets the design requirements. The flame correction temperature is controlled at 600℃~800℃, and overburning is strictly prohibited. It is strictly prohibited to hammer or use water to accelerate cooling before the temperature drops to room temperature. When correcting, the workpiece should be leveled, the cause of deformation should be analyzed, and the heating point, heating temperature, heating area, etc. should be correctly selected. The number of heating times at the same position should not exceed 2 times.

[0129] When assembling and welding components, the joints with larger shrinkage should be welded first, and then the joints with smaller shrinkage. The joints should be welded under the smallest restraint state; combined components composed of multiple components should be assembled and welded in parts, and the final assembly welding should be carried out after the deformation of the unit components is corrected.

[0130] After the welding of the filling layer weld is completed, the weld can be hammered with a pneumatic shovel, ultrasonic stress relief instrument, or a vibration hammer. The hammer head of the vibration hammer must be round or smoothly transitioned. It is strictly forbidden to use a sharp hammer head for hammering. It is strictly forbidden to hammer the bottom layer and cover layer welds. The filling layer should be hammered every two layers to relieve stress. When hammering, the surface temperature of the weld should be no more than 150℃.

[0131] During the welding process, the generation of residual stress is closely related to the welding quality, and the welding quality will also have an important impact on the generation of residual stress.

[0132] When controlling the welding quality of full penetration welds, the welding procedure assessment should be made according to Appendix H of JTG / T 3650-2020 Technical Specifications for Highway Bridge and Culvert Construction based on different welding methods, joint forms, steel materials, plate thickness, welding materials, etc. before welding. The welding procedure specification (WPS) of the corresponding joint is compiled based on the welding procedure assessment, and the parameters of each weld by the welder must be based on the corresponding welding procedure specification (WPS) for welding.

[0133] Before welding, the parent material must be sufficiently clean to allow the production of welds that meet the quality requirements of the specification. The surface and both sides of the parent material to be welded should be uniform and smooth, and should be free of burrs, tears, cracks, residues and other defects defined by the technical conditions of the parent material. The surface to be welded and within 30mm of the edge of the weld groove should not have impurities such as scale, rust, grease, water, etc. that affect normal welding and weld quality. The arc starter and extinguisher plates of the weld must be set according to the "Process Requirements for Arc Starter Plates, Arc Extinguishers and Backing Plates" in the general process to ensure the welding quality of the weld ends. In order to prevent cracks, the preheating temperature must be ensured to meet the WPS requirements before welding, and the preheating temperature and interpass temperature must be checked before each weld is about to start the arc. The dimensions of the weld groove, blunt edge and root gap should meet the requirements of the drawings. Before welding, the flux to be used should be dried as required according to the general process "Storage and Drying Requirements for Domestic and Foreign Welding Materials".

[0134] During the welding process, the welder should hang the welding procedure specification (WPS) of the corresponding weld on the welding machine. The welding parameters used should be within the range of the welding procedure specification (WPS). The minimum interpass temperature is equal to the preheating temperature, and the maximum interpass temperature is not higher than 230℃. In the case of multi-layer and multi-pass welding, the welding slag, slag inclusions, oxides, etc. between the welds or weld layers should be strictly removed during the welding process. Grinding wheels, chisels, wire brushes and other tools can be used for cleaning. In the case of multi-layer and multi-pass welding, the end of the weld should be made into a gentle transition with a slope of no more than 1:2.5. The length of the weld between each layer is the same, and the different layers are made into steps. After the weld is completed, the weld end can be polished to form a gentle transition of no more than 1:2.5. The width-to-depth ratio of each weld should not be less than 1.1 (the width-to-depth ratio is the value of B / H in the figure below). The maximum single-pass weld layer width is shown in Table 3 below.

[0135] Table 3: Maximum single-pass weld layer width:

[0136]

[0137] The width of the final multi-pass cap weld shall not exceed 1.6 times the plate thickness.

[0138] After welding is completed, clean the slag and metal splashes on the surface of the weld, and the welder shall check the appearance quality of the weld by himself; if it does not meet the requirements, it shall be welded or polished. The repaired weld shall be smooth and round, and shall not affect the appearance quality requirements of the original weld. After welding is completed and the weld has cooled to room temperature, all welds shall be visually inspected. The welds shall not have cracks, incomplete fusion, slag inclusions, unfilled arc pits, leaks, and defects beyond those specified in Table 8.6.1 of JTG / T 3650-2020 "Technical Specifications for Highway Bridge and Culvert Construction". Nondestructive testing can only be carried out after the weld has passed the appearance inspection, and nondestructive testing should be carried out 24 hours after welding. The quality grading, inspection method, inspection location and level of nondestructive testing of welds shall comply with the provisions of Table 8.6.2 of JTG / T 3650-2020 "Technical Specifications for Highway Bridge and Culvert Construction". Ultrasonic flaw detection of welds shall comply with the provisions of GB / T11345-2013 "Ultrasonic testing technology, testing levels and assessment for non-destructive testing of welds", and magnetic particle testing shall comply with the current "Magnetic particle testing for non-destructive testing of welds" (GB / T26951) and "Acceptance levels for magnetic particle testing for non-destructive testing of welds" (GB / T 26952).

[0139] The simulation analysis method of residual stress in U-rib welding of steel box girder is studied, and a suitability model for simulating welding heat source is proposed. The influencing parameter analysis and simulation analysis of residual stress state are carried out to find out the sensitive parameters.

[0140] Nondestructive testing technology and application of residual stress of steel box girders, improvement of ultrasonic-based detection methods and technical methods for data correction processing, and verification of the residual stress state of steel box girders through detection applications.

[0141] A comparative study of engineering measures to reduce residual stress was conducted, and reasonable measures to eliminate residual stress were proposed and used for the welding process control of steel box girders.

[0142] We developed a mobile water operation platform, which uses steel to assemble a cantilever hanger, solving the problem of water operations that cannot be carried out with large lifting equipment and reducing construction costs. The use of pulleys to achieve the movement and positioning of the mobile platform is simple and practical.

[0143] Digital technology equipment is used to push the steel box girder, and remote control and on-site data detection are used to ensure the construction safety and bridge accuracy of the steel box girder during the pushing process.

[0144] The research on residual stress in this project was carried out by using ABAQUS and other software for numerical simulation and analyzing the application in the actual project. The main analysis results are as follows:

[0145] The temperature of the first and second welds of the U-rib of the bridge deck rises rapidly at the initial stage of welding, and is basically welded in a steady state during the subsequent welding process. The temperature changes greatly in front of the center of the heat source, and the temperature changes less in the rear. Whether in the direction of the weld or perpendicular to the weld, the time history curve of the overall temperature field has two peaks, and the temperature of the first peak is greater than the second peak.

[0146] Residual stress distribution of the top plate: The peak value of the equivalent stress of top plate paths 1, 2, and 3 appears at the center of the weld. It can be clearly seen that the equivalent stress is symmetrically distributed from the center of the weld to the outside. The farther away from the center of the weld, the smaller the equivalent stress is, and it approaches 0 at the farthest end; there is a peak area of ​​about 0.03m near the weld area along the weld direction, and the peak value of the residual tensile stress reaches about 370MPa, which exceeds the yield strength of the material. As the distance from the weld increases, the residual tensile stress on both sides gradually decreases to about 0MPa. The residual stress distribution of paths 1, 2, and 3 along the plate thickness direction is very uneven, and the residual stress fluctuates greatly at the position close to the weld. In the area far away from the weld, the transverse residual stress has almost no change and can be ignored; the residual stress distribution perpendicular to the weld direction is symmetrically distributed with the weld as the axis. And the peak residual stress appears at a position 1.5 times the thickness of the top plate from the weld, and the residual tensile stress gradually decreases from the weld position to both sides.

[0147] U-rib residual stress distribution: The distribution and variation trend of equivalent stress on different paths of U-rib are almost the same. After the equivalent stress not far from the weld decreases, it increases, and the equivalent stress on the three paths is evenly distributed along the thickness of the U-rib. As the distance from the weld increases, the equivalent stress eventually tends to about 0MPa; along the weld direction, the distribution and variation trend of longitudinal residual stress on different paths are almost the same. The maximum value of residual tensile stress in paths 1, 2, and 3 close to the weld is between 350 and 400MPa, which exceeds the yield limit of the material; the residual stress in the thickness direction of the U-rib gradually decreases from paths 1 to 3. The peak value of residual tensile stress in the thickness direction of the U-rib is the highest in path 1, followed by path 2, while path 3 has almost no residual tensile stress in the thickness direction of the U-rib, and the peak value of residual compressive stress is 20MPa; the transverse residual of the U-rib perpendicular to the weld direction is relatively small even in the weld area, and the residual stress beyond the weld area is almost negligible.

[0148] As the thickness of the top plate increases, the peak value of the longitudinal residual tensile stress of the top plate also increases, while the residual stress values ​​on both sides of the weld decrease as the distance from the weld increases and gradually decreases to 0. The residual stress of the U-rib plate also increases with the increase in plate thickness, resulting in a continuous increase in the peak value of the residual tensile stress, and the residual compressive stress value in the area 0.02m away from the weld is constantly decreasing; as the groove angle increases, the peak value of the residual tensile stress of the top plate in the weld and its vicinity becomes smaller and smaller. On both sides of the weld, the farther the distance, the smaller the residual stress and tends to 0. The residual tensile stress of the U-rib plate increases with the increase in the groove angle near the weld, and the residual compressive stress value shows a decreasing trend. The increase in welding speed will reduce the peak tensile stress of the top plate, the location of the residual tensile stress is closer to the weld, and the peak compressive stress of the U rib is reduced.

[0149] Three U-rib top plate unit welding schemes were designed for this project, and a comparative analysis was conducted to study the influence of welding sequence on welding temperature field and welding residual stress. Through simulation calculation of the welding process, the calculation result data was extracted. Through comparative analysis, it can be seen that the change of welding residual stress is relatively complex, but in general, it can be known that the longitudinal welding residual stress is more evenly distributed in the weld area and the peak value is relatively low when the symmetrical welding sequence is compared with the asymmetrical welding sequence. When the sequence of multiple welding is adopted, the peak value of the longitudinal welding residual stress is also significantly reduced due to the significant reduction in the heat affected range of the single welding. It can be seen that the welding sequence of symmetrical welding and reducing the welding heat affected range is generally more advantageous, and the influence of the welding process on the welding residual stress is complex.

[0150] Based on the same technical concept, in a second aspect, the present invention proposes a residual stress detection device for a large-span steel box girder, comprising:

[0151] A detection position determination module, used for setting a plurality of detection positions on the long-span steel box girder and distributed in the welding area at intervals along the circumferential direction;

[0152] An ultrasonic detection module, used to perform real-time ultrasonic detection on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions;

[0153] A graphing module, used for making the real-time residual stress data corresponding to each of the detection positions into a line graph;

[0154] The result acquisition module is used to analyze the line graph in sequence to obtain the residual stress detection result of the welding area corresponding to each detection position.

[0155] It should be noted that the functions that can be realized by each module in the residual stress detection device for large-span steel box girders provided in this embodiment and the corresponding technical effects achieved can refer to the description of the specific implementation methods in each embodiment of the residual stress detection method for large-span steel box girders of the present invention. For the sake of brevity of the specification, they will not be repeated here.

[0156] Based on the same technical concept, in a third aspect, the present invention proposes a residual stress detection system for a large-span steel box girder, comprising:

[0157] Ultrasonic testing equipment; and,

[0158] A residual stress detection device is communicatively connected to the ultrasonic detection instrument to implement the residual stress detection method for a large-span steel box girder described in the first aspect.

[0159] It should be noted that the functions that can be realized by each module in the residual stress detection system for large-span steel box girders provided in this embodiment and the corresponding technical effects achieved can refer to the description of the specific implementation methods in each embodiment of the residual stress detection method for large-span steel box girders of the present invention. For the sake of brevity of the specification, they will not be repeated here.

[0160] Based on the same technical concept, in the fourth aspect, the present invention proposes a large-span steel box girder residual stress detection device, the large-span steel box girder residual stress detection device includes a processor and a memory, the memory stores a large-span steel box girder residual stress detection program, and when the large-span steel box girder residual stress detection program is executed by the processor, the large-span steel box girder residual stress detection method described in the first aspect is implemented.

[0161] The residual stress detection equipment for large-span steel box girders refers to terminal equipment or network equipment that can achieve network connection. The residual stress detection equipment for large-span steel box girders can be terminal equipment such as mobile phones, computers, tablet computers, embedded industrial computers, or network equipment such as servers and cloud platforms.

[0162] like Fig.36 , which is a schematic diagram of the hardware structure of a residual stress detection device for a large-span steel box girder. The residual stress detection device for a large-span steel box girder may include: a processor 1001, such as a CPU (Central Processing Unit), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005.

[0163] Those skilled in the art will understand that Fig.36 The hardware structure shown in the figure does not constitute a limitation on the residual stress detection device for a large-span steel box girder of the present invention, and may include more or fewer components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0164] Specifically, the communication bus 1002 is used to realize the connection and communication between these components;

[0165] The user interface 1003 is used to connect to the client and perform data communication with the client. The user interface 1003 may include an output unit, such as a display screen, and an input unit, such as a keyboard;

[0166] The network interface 1004 is used to connect to the backend server and perform data communication with the backend server. The network interface 1004 may include an input / output interface, such as a standard wired interface, a wireless interface, such as a Wi-Fi interface;

[0167] The memory 1005 is used to store various types of data, which may include, for example, instructions for any application or method in the long-span steel box girder residual stress detection device, as well as data related to the application. The memory 1005 may be a high-speed RAM memory or a stable memory, such as a disk memory. Optionally, the memory 1005 may also be a storage device independent of the processor 1001, and further reference is made to Figure 8 , the memory 1005 may include an operating system, a network communication module, a user interface module, and a residual stress detection program for a large-span steel box girder;

[0168] The processor 1001 is used to call the long-span steel box girder residual stress detection program stored in the memory 1005, and perform the following operations:

[0169] Based on the same technical concept, in the fifth aspect, the present invention proposes a computer storage medium, on which a computer program is stored. When the computer program is executed by one or more processors, the method for detecting residual stress of a large-span steel box girder described in the first aspect is implemented.

[0170] S100, setting a plurality of detection positions on the long-span steel box girder and distributed in the welding area at intervals along the circumferential direction;

[0171] S200, performing real-time ultrasonic testing on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions;

[0172] S300, making the real-time residual stress data corresponding to each detection position into a line graph;

[0173] S400, analyzing the line graph in sequence to obtain residual stress detection results of the welding area corresponding to each detection position.

[0174] Based on the same inventive concept, this embodiment provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (for example, an SD or DX memory, etc.), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic memory, a disk, an optical disk, a server, etc., on which a computer program is stored, and the computer program can be executed by one or more processors. When the computer program is executed by the processor, all or part of the steps of each embodiment of the residual stress detection method for a large-span steel box girder of the present invention can be implemented.

[0175] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for detecting residual stress of a large-span steel box girder, characterized in that: A welding area is formed on the long-span steel box girder, and a weld is formed in the welding area; The method for detecting residual stress of a large-span steel box girder comprises the following steps: A plurality of detection positions are arranged on the large-span steel box girder and are distributed in the welding area at intervals along the circumferential direction; wherein the plurality of detection positions are paired in pairs and are relatively distributed on both sides of the weld; Performing real-time ultrasonic testing on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions; Making the real-time residual stress data corresponding to each of the detection positions into a line graph; The line graphs are analyzed in sequence to obtain residual stress detection results of the welding area corresponding to each detection position.

2. The method for detecting residual stress of a large-span steel box girder according to claim 1, characterized in that: The step of setting a plurality of detection positions on the long-span steel box girder and distributed at intervals along the circumferential direction in the welding area comprises: A plurality of detection positions are arranged on the long-span steel box girder, which are circumferentially spaced apart in the welding area and are at a target distance from the weld.

3. The method for detecting residual stress of a large-span steel box girder according to claim 2, characterized in that: The target distance is A, where 2cm≤A≤6cm.

4. The method for detecting residual stress of a large-span steel box girder according to claim 3, characterized in that: The center distance between any two adjacent welding positions on the same side of the weld is B, where 20 cm ≤ 60 cm.

5. The method for detecting residual stress of a long-span steel box girder according to any one of claims 1 to 4, characterized in that: The step of sequentially performing real-time ultrasonic testing on each of the detection positions to obtain real-time residual stress data corresponding to each of the detection positions comprises: Performing grinding construction on each of the detection positions in turn; An ultrasonic testing instrument is installed at each of the testing positions after the grinding construction is completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions.

6. The method for detecting residual stress of a large-span steel box girder according to claim 5, characterized in that: The step of installing an ultrasonic testing instrument at each of the testing positions after the grinding construction is completed to perform real-time ultrasonic testing to obtain real-time residual stress data corresponding to each of the testing positions includes: After the grinding construction is completed, a coupling agent is applied to each of the detection positions and an ultrasonic detection instrument is installed to perform real-time ultrasonic detection to obtain real-time residual stress data corresponding to each of the detection positions.

7. A residual stress detection device for a large-span steel box girder, characterized in that: include: A detection position determination module, used for setting a plurality of detection positions on the long-span steel box girder and distributed in the welding area at intervals along the circumferential direction; An ultrasonic detection module, used to perform real-time ultrasonic detection on each of the detection positions in turn to obtain real-time residual stress data corresponding to each of the detection positions; A graphing module, used for making the real-time residual stress data corresponding to each of the detection positions into a line graph; The result acquisition module is used to analyze the line graph in sequence to obtain the residual stress detection result of the welding area corresponding to each detection position.

8. A residual stress detection system for a large-span steel box girder, characterized in that: include: Ultrasonic testing equipment; as well as, A residual stress detection device, wherein the residual stress detection device is communicatively connected to the ultrasonic detection instrument, so as to implement the residual stress detection method for a large-span steel box girder as described in any one of claims 1 to 6.

9. A residual stress detection device for a large-span steel box girder, characterized in that: The large-span steel box girder residual stress detection device includes a processor and a memory, and the memory stores a large-span steel box girder residual stress detection program. When the large-span steel box girder residual stress detection program is executed by the processor, the large-span steel box girder residual stress detection method according to any one of claims 1 to 6 is implemented.

10. A computer storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by one or more processors, the method for detecting residual stress of a large-span steel box girder according to any one of claims 1 to 6 is implemented.

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