Method for welding reinforcement mesh for bridge construction

Abstract

The present application relates to the technical field of welding, in particular to a reinforcing mesh welding method for bridge construction, comprising: applying pre-tension to a plurality of first reinforcing bars arranged at a set interval in a first direction respectively, so that the first reinforcing bars remain in a straight line state and the two ends are fixed; placing a plurality of second reinforcing bars in a second direction on the first reinforcing bars one by one to form perpendicular intersection points; acquiring the actual position of the intersection points in real time through a detection system, and acquiring the gap value between the first reinforcing bars and the second reinforcing bars at the actual position in real time; driving a welding gun to perform adaptive displacement compensation based on the deviation value between the actual position and the design position; and dynamically adjusting the welding pressure based on the gap value to complete welding at the compensated position. The reinforcing mesh welding method for bridge construction introduces pre-tension control, real-time detection and adaptive compensation mechanism, solves the position deviation and gap problem caused by the bending of the reinforcing bars, and realizes efficient and high-quality automatic welding of the reinforcing mesh.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of welding technology, in particular to a reinforcing mesh welding method for bridge construction. BACKGROUND

[0002] In bridge engineering, reinforcing mesh is the core framework of concrete structure, and its welding quality directly affects the structural strength and durability. The traditional on-site binding steel technology has problems such as high labor cost, low efficiency and serious material waste. Although the popularization of factory welding mesh technology can improve the laying efficiency, reduce the labor cost, and reduce the on-site waste, the technology still faces key bottlenecks.

[0003] Specifically, long-size steel bars are naturally bent due to transportation and storage, and the actual position of the intersection deviates from the design coordinates during laying, forcing on-site secondary correction, which offsets the efficiency advantage of factory production; irregular gaps are formed at the intersection of bent steel bars, and the virtual welding rate increases when the gap is too large in traditional constant pressure welding, which requires manual repair welding, increasing the quality risk and delaying the construction period. SUMMARY

[0004] The present application provides a reinforcing mesh welding method for bridge construction, which can effectively solve the problems pointed out in the background art.

[0005] In order to achieve the above purpose, the technical scheme adopted by the present application is:

[0006] The reinforcing mesh welding method for bridge construction comprises:

[0007] A plurality of first steel bars arranged in a first direction at a set interval are respectively subjected to pre-tensioning, so that the first steel bars remain in a straight line state and the two ends are fixed;

[0008] A plurality of second steel bars arranged in a second direction at a set interval are placed on the first steel bars one by one, forming perpendicular intersection points;

[0009] For each second steel bar, the actual position of each intersection point is obtained by a detection system in sequence, and the gap value between the first steel bar and the second steel bar at the actual position is obtained in real time;

[0010] Based on the deviation value between the actual position and the design position, a welding gun is driven to perform adaptive displacement compensation during continuous welding of each intersection point;

[0011] Based on the gap value, the welding pressure is dynamically adjusted, and the welding is completed at the compensated position.

[0012] Further, the actual position of each intersection point is obtained by a detection system in sequence, comprising:

[0013] An image of the intersection region is collected by a visual sensor, and the center point coordinates of the overlapping region of the first and second reinforcing bars are determined based on an image recognition algorithm, as the actual position of the intersection.

[0014] Further, the gap value between the first and second reinforcing bars at the actual position is obtained in real time, including:

[0015] A laser beam is vertically emitted above the center point coordinates, and ranging data of the laser beam to the surface of the second reinforcing bar is obtained;

[0016] The gap value is calculated based on the ranging data.

[0017] Further, when the gap value is greater than a set threshold, the following is performed:

[0018] The gap value is re-detected after adjusting the position of the second reinforcing bar;

[0019] If the gap value is less than or equal to the set threshold, welding is performed;

[0020] If the gap value is still greater than the set threshold after N consecutive adjustments, the second reinforcing bar is replaced, where N≥3.

[0021] Further, in the process of repeatedly welding reinforcing mesh of the same model, the probability value of each intersection point of each second reinforcing bar exceeding the set threshold is continuously counted;

[0022] For welding of each second reinforcing bar, all welding positions are sorted in order of the probability value from low to high.

[0023] Further, adjusting the position of the second reinforcing bar includes:

[0024] A vibrator is installed at the fixed end of the first reinforcing bar;

[0025] The vibrator is controlled to drive the first reinforcing bar to vibrate at a frequency of 20 to 50 Hz;

[0026] The second reinforcing bar is displaced in the direction of gravity through contact and conduction of vibration between the first and second reinforcing bars.

[0027] Further, the actual position of each intersection point is obtained, including:

[0028] Four corner points of the overlapping region of the two reinforcing bars in the image are identified;

[0029] Two straight lines are obtained by connecting two pairs of opposite corner points;

[0030] The intersection point of the two straight lines is taken as the center point coordinates of the overlapping region of the first and second reinforcing bars.

[0031] Further, the welding comprises:

[0032] At the actual position of the intersection point, a double electrode head of an electric resistance welding machine is used to apply a pre-pressure to the overlapped first steel bar and second steel bar, and the pre-pressure is adjusted according to the gap value;

[0033] A first current is passed in a state of maintaining the pre-pressure, and a contact resistance dynamic value and an electrode pressure fluctuation value are monitored in real time, and when the contact resistance dynamic value is less than a first threshold value and the absolute value of the electrode pressure fluctuation value is less than a second threshold value, a first stage is completed and a second stage is entered;

[0034] A second current higher than the first current is switched to, and a dynamic resistance decay slope is monitored synchronously, and when the dynamic resistance decay slope is less than a third threshold value, the welding is completed by stopping the current passing.

[0035] Further, the first current is 40% to 60% of the rated current of the electric resistance welding machine, and the second current is 70% to 90% of the rated current of the electric resistance welding machine.

[0036] Further, a descending rate of the first stage contact resistance dynamic value is recorded, and if the descending rate is less than a fourth threshold value, the corresponding welding point is marked as a potential false welding point.

[0037] Through the technical scheme of the present application, the following technical effects can be achieved:

[0038] In the present application, a pre-tension is applied to the first steel bar and both ends are fixed to forcibly maintain a straight state, effectively overcoming the natural bending of long-size steel bars during transportation and storage. The second steel bar is placed and welded one by one, and the actual position of the intersection point and the gap value are obtained in real time by a detection system, and the welding gun is driven to adaptively compensate based on the deviation value, realizing accurate alignment of the intersection point without the need for manual measurement or correction, ensuring the geometric accuracy of the reinforcement mesh. At the same time, the welding pressure is dynamically adjusted based on the gap value, solving the welding defects caused by the gap at the intersection of the bent steel bar, reducing the false welding rate, and avoiding the need for manual repair welding.

[0039] The steel reinforcement mesh welding method for bridge construction of the present application solves the problems of position deviation and gap caused by steel bending by introducing a pre-tension control, real-time detection and adaptive compensation mechanism, realizing efficient and high-quality automatic welding of steel reinforcement mesh. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only show some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0041] Figure 1 A flow chart of a reinforcing mesh welding method for bridge construction;

[0042] Figure 2 A distribution diagram of the first reinforcing bar and the second reinforcing bar; Figure 2

[0043] A plan view of the reinforcing mesh; Figure 3

[0044] A displacement diagram of four corner points of the overlapping area of the two reinforcing bars; Figure 4

[0045] A flow chart of the welding process; Figure 5 Reference signs:

[0046] 1, first reinforcing bar; 2, second reinforcing bar; 3, fixed area; 4, center point.

[0047] DETAILED DESCRIPTION The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments.

[0048] A reinforcing mesh welding method for bridge construction, as shown in and

[0049] , comprises: Figure 1 2 S1: a pre-tension is applied to each of the first reinforcing bars 1 arranged in the first direction at a set interval, so that the first reinforcing bars 1 are kept in a straight line state and the two ends are fixed, as shown in , a fixed area 3 is formed at the end; in this embodiment, the pre-tension needs to be ensured to be less than 60% of the yield strength of the first reinforcing bars 1 to avoid plastic deformation, and at the same time, the sag of the first reinforcing bars 1 is ensured to be less than or equal to 20 mm under a 20 m span;

[0050] Figure 2 S2: the second reinforcing bars 2 arranged in the second direction at a set interval are placed on the first reinforcing bars 1 one by one to form vertical intersection points; wherein the set intervals in steps S1 and S2 can be the same, or different interval values can be selected according to needs;

[0051] S2: the second reinforcing bars 2 arranged in the second direction at a set interval are placed on the first reinforcing bars 1 one by one to form vertical intersection points; wherein the set intervals in steps S1 and S2 can be the same, or different interval values can be selected according to needs;

[0052] S3: For each second steel bar 2, the actual position of each intersection is sequentially acquired by the detection system, and the gap value between the first steel bar 1 and the second steel bar 2 at the actual position is acquired in real time;

[0053] S4: Based on the deviation value between the actual position and the design position, the welding gun is driven to perform adaptive displacement compensation during continuous welding of each intersection;

[0054] S5: Based on the gap value, the welding pressure is dynamically adjusted, and welding is completed at the compensated position, thereby realizing precise welding of each second steel bar 2.

[0055] In the present application, the first steel bar 1 is subjected to pre-tension and fixed at both ends, and is forced to maintain a straight state, effectively overcoming the natural bending of long-size steel bars during transportation and storage. The second steel bar 2 is placed and welded one by one, reducing the difficulty of the equipment, and the actual position of the intersection and the gap value are acquired in real time by the detection system. Based on the deviation value, the welding gun is driven to perform adaptive displacement compensation, realizing accurate alignment of the intersection without the need for manual measurement or correction, ensuring the geometric accuracy of the reinforcement mesh. At the same time, based on the gap value, the welding pressure is dynamically adjusted, solving the welding defects caused by the gap at the intersection of the bent steel bar, reducing the rate of false welding, and avoiding the need for manual repair welding.

[0056] The bridge construction reinforcement mesh welding method of the present application introduces pre-tension control, real-time detection and adaptive compensation mechanism to solve the position deviation and gap problem caused by the bending of the steel bar, and realizes efficient and high-quality automatic welding of the reinforcement mesh.

[0057] As a preferred embodiment of the above embodiment, the actual position of each intersection is sequentially acquired by the detection system, as shown in Figure 3 , including: acquiring the image of the intersection area by the vision sensor, determining the center point 4 coordinate of the overlapping area of the first steel bar 1 and the second steel bar 2 based on the image recognition algorithm, as the actual position of the intersection.

[0058] In the scene of bridge reinforcement mesh welding, the vision sensor is preferably an industrial-grade CCD or CMOS camera, and the resolution can be selected to be more than 2 million pixels; in order to achieve better image acquisition, a ring-shaped LED light source can be further matched around the overlapping area in the implementation process, to a certain extent, overcoming the image noise caused by environmental light interference and steel surface defects.

[0059] In this preferred embodiment, the image recognition algorithm includes but is not limited to existing technical methods such as edge detection and feature point matching, and accurately locates the geometric center coordinates of the overlapping area of the two steel bars, realizing non-contact measurement of the actual position of the intersection.

[0060] As a preferred embodiment of the above, the gap value between the first reinforcing bar 1 and the second reinforcing bar 2 is obtained in real time at the actual position, comprising: vertically emitting a laser beam directly above the center point 4 coordinate, and obtaining ranging data of the laser beam to the surface of the second reinforcing bar 2; and calculating the gap value based on the ranging data.

[0061] In the implementation process, the first reinforcing bar 1 and the second reinforcing bar 2 are cross-laminated through point contact. In the preferred embodiment, the reflection point of the laser on the surface of the second reinforcing bar 2 is directly above the point contact position. Based on the first reinforcing bar 1 with fixed and high data readability, when there is no gap between the first reinforcing bar 1 and the second reinforcing bar 2, the ranging data indirectly reflects that the vertical distance between the laser reflection point and the point contact position on the second reinforcing bar 2 is the diameter of the second reinforcing bar 2; when the distance between the laser reflection point and the point contact position on the second reinforcing bar 2 is greater than the diameter of the second reinforcing bar 2, the gap value can be obtained by calculating the difference between the diameter of the second reinforcing bar 2.

[0062] The relatively accurate center point 4 coordinate determined based on the actual posture of the second reinforcing bar 2 and the gap value corresponding to the point can provide relatively accurate data reference for the welding pressure, which is key and beneficial for real-time parameter adjustment in the automatic welding process. Of course, in the implementation process, if the deviation between the center point 4 coordinate and the set coordinate is too large, a prompt alarm can be given, and the welding performed in the embodiment is based on the premise that the position of the center point 4 coordinate is controllable.

[0063] As a preferred embodiment of the above, when the gap value is greater than a set threshold value, the following is performed:

[0064] Adjusting the position of the second reinforcing bar 2 and re-detecting the gap value;

[0065] If the gap value is less than or equal to the set threshold value, welding is performed;

[0066] If the gap value is still greater than the set threshold value after N times of continuous adjustment, the second reinforcing bar 2 is replaced, where N≥3.

[0067] In the embodiment, the welding of the second reinforcing bar 2 is performed after all gap values meet the requirements, and the replacement of the second reinforcing bar 2 is required if the gap value at any position still does not meet the requirements after adjustment. In the preferred embodiment, the implementation of the position adjustment action can eliminate accidental errors, and the reasonable determination of the value of N can identify systematic defects, such as reinforcing bar bending. In this case, replacing the second reinforcing bar 2 can block the flow of defective products into the next process.

[0068] As a preferred embodiment of the above, the set threshold value corresponding to the gap value can be specifically set to 0.5 to 1.2 mm, and more preferably, it can be set to 0.7 to 0.9 mm.

[0069] As a preferred embodiment of the above, during the repeated welding of the same type of steel mesh, the probability value of the gap value exceeding the set threshold at each intersection of each second steel bar 2 is continuously counted; for the welding of each second steel bar 2, all welding positions are sorted according to the probability value from low to high.

[0070] In this preferred scheme, intelligent sorting of welding positions for individual rebars and optimization of the welding execution sequence using historical out-of-tolerance probability data can improve the welding efficiency and quality stability of individual rebars. Specifically, for multiple welding positions on a single second rebar 2, prioritizing the welding of low-probability points with high structural stability establishes rigid support anchor points, dividing the long rebar into multiple short spans. When welding high-probability points subsequently, local thermal deformation is confined to a small range between adjacent anchor points, preventing continuous transmission and superposition along the length direction, thereby reducing the overall deformation. Simultaneously, the compressive residual stress generated by the cooling and shrinkage of the first welded points can partially offset the initial gap of the high-probability points, forming a mechanical pre-compensation effect.

[0071] As a preferred embodiment of the above, adjusting the position of the second reinforcing bar 2 includes:

[0072] A vibrator is installed at the fixed end of the first reinforcing bar 1;

[0073] The vibrator is controlled to drive the first steel bar 1 to vibrate at a frequency of 20 to 50 Hz.

[0074] Vibration is transmitted through the contact between the first reinforcing bar 1 and the second reinforcing bar 2, causing the second reinforcing bar 2 to shift in the direction of gravity.

[0075] In this preferred embodiment, each first reinforcing bar 1 in each steel mesh can be fixed by the same fixed structure, allowing the vibration energy of the vibrator to be transmitted to each first reinforcing bar 1 through the fixed structure. The vibration energy is directionally transmitted through the point contact position, driving the second reinforcing bar 2 to produce a pure translational micro-displacement in the direction of gravity. The amplitude can be specifically controlled to be below 0.5mm, enabling the second reinforcing bar 2 to accurately settle into place without external prying. At the same time, the first reinforcing bar 1 maintains its original position due to the fixed end constraint and high rigidity characteristics, achieving gap closure without disturbing the calibrated coordinate reference. The frictional force at the contact point forms displacement isolation, effectively suppressing the transmission of lateral displacement and ensuring the stability of the second reinforcing bar 2 after position adjustment.

[0076] As a preferred embodiment of the above, such as Figure 4 As shown, the actual positions of each intersection point are obtained, including:

[0077] Identify the four corner points of the overlapping area between two steel bars in the image, i.e. Figure 4 Points A, B, C, and D shown in the diagram,

[0078] Connect two pairs of diagonal points to obtain two straight lines, namely line AD and line BC in the figure;

[0079] The intersection of the two straight lines is taken as the center point coordinate of the overlapping area of the first reinforcing bar 1 and the second reinforcing bar 2, i.e. Figure 4 the point M shown in the figure, as the actual position of the intersection.

[0080] In actual production, the deformation of the second reinforcing bar 2 at any welding point is often manifested as a slight shift in position in the image, as shown in the figure from points A, B, C, D to points A', B', C', D'. By actually obtaining the four shifted points and correspondingly obtaining the straight line A'D' and the straight line B'C', the actual position point M' of the deformed intersection can be obtained.

[0081] In this preferred embodiment, by identifying the four deformation-sensitive corner points of the reinforcing bar intersection overlapping area, connecting the opposite corners to construct two virtual reference lines, and taking the intersection M as the actual intersection coordinate after deformation compensation, when the second reinforcing bar 2 has a local shift, the intersection M' based on the new opposite corners can accurately represent the true intersection position, so that the subsequent laser gap measuring reference point always coincides with the mechanical contact point, eliminating the positioning error caused by the deformation of the reinforcing bar from the root, and ensuring the required welding positioning accuracy.

[0082] As a preferred embodiment of the above, as shown in Figure 5 the welding comprises:

[0083] A1: At the actual position of the intersection, a pre-pressure is applied to the overlapping first reinforcing bar 1 and second reinforcing bar 2 by the double electrode head of the resistance welding machine, and the pre-pressure is adjusted according to the gap value;

[0084] A2: In the state of maintaining the pre-pressure, a first current is passed, the dynamic value of the contact resistance and the absolute value of the electrode pressure fluctuation value are monitored in real time, when the dynamic value of the contact resistance is less than a first threshold value, and the absolute value of the electrode pressure fluctuation value is less than a second threshold value, the first stage is completed and the second stage is entered;

[0085] A3: Switch to a second current higher than the first current, and simultaneously monitor the dynamic resistance decay slope, when the dynamic resistance decay slope is less than a third threshold value, stop power supply to complete welding.

[0086] In the implementation process, the resistance welding machine synchronously applies axial pressure through the upper and lower electrode heads, specifically, the pressure range can be adjusted according to the gap value between 3kN and 6kN; when power is supplied, the current forms a closed loop through the double electrodes, generating Joule heat in the reinforcing bar overlapping area to realize local fusion connection.

[0087] In the first stage, the first current is preferably 40% to 60% of the rated current, such as a current value range of 8 kA to 12 kA; this stage is preferentially used to break the surface oxide layer and micro convex points of the steel bar, and the interface micro fusion is achieved through the medium current and the pre-pressure; if the current is too low, the initial molten core will be discontinuous, and if the current is too high, it will cause early spatter; through the reasonable selection of the first current, the stable formation of the initial molten core can be ensured. In this stage, the dynamic value of the contact resistance represents the process of the metallurgical reaction of the welding interface; specifically, when the power is initially turned on, the resistance is high due to the surface oxide layer and the micro unevenness of the steel bar; as the micro convex points melt and spread under the action of the pre-pressure, the effective contact area increases, and the resistance value dynamically decreases; when it decreases to the first threshold value, which is preferably 80 μΩ in the embodiment, it indicates that a continuous liquid metal layer has been formed on the interface, and the basis for the stable formation of the molten core is ready. The fluctuation value of the electrode pressure reflects the mechanical stability of the molten core growth process; specifically, the electrode pressure should remain constant in the ideal state, and when the absolute value of the fluctuation exceeds the second threshold value, which is preferably 150 N in the embodiment, it indicates that there is an abnormality; among them, the negative fluctuation indicates that the molten core may be caused to shrink due to local collapse, and the positive fluctuation indicates the risk of spatter; by controlling the fluctuation within the threshold value, structural defects can be prevented.

[0088] In the second stage, the second current is preferably 70% to 90% of the rated current, such as a current value range of 14 kA to 18 kA; based on the stable molten core that has been formed, high current is used to achieve the deep extension of the molten core in this stage; if the current is too low, the penetration depth will be insufficient, and if the current is too high, the grains will be coarsened due to the rapid accumulation of heat. In this stage, the dynamic resistance decay slope indicates the saturation state of the molten core depth, specifically, the high current in the second stage causes the molten core to grow centripetally, and the resistance continues to decay slowly due to heat diffusion; when the penetration depth reaches a certain degree, the resistance change tends to be stationary, indicating that the penetration is complete, at which time the power is turned off to avoid grain coarsening caused by overburning and to ensure the toughness of the weld point; in the embodiment, the third threshold value is preferably 0.5 μΩ / ms.

[0089] As a preferred embodiment of the above embodiment, the rate of decline of the dynamic value of the contact resistance in the first stage is recorded, and if the rate of decline is less than the fourth threshold value, the weld point is marked as a potential false weld point. In the preferred scheme, by monitoring the dynamic rate characteristics of the welding process in real time, a two-level quality evaluation system is constructed, specifically: when the rate of decline of the dynamic value of the contact resistance in the first stage is less than the fourth threshold value, which is preferably 1.8 to 2.5 μΩ / ms in the embodiment, it indicates that the interface molten core expansion is slow, which may be caused by oil stains or an excessively thick oxide layer, and needs to be marked as a false weld risk point accordingly.

[0090] As a preferred embodiment of the above-mentioned embodiment, the acquisition of the dynamic value of the contact resistance can be measured in real time by a separate four-wire method probe installed on the electrode arm, the separate probe directly acquires a voltage signal within the near field of the welding spot, such as within 10 mm, using the electrode arm as a current conduction path; and the acquisition of the fluctuation value of the electrode pressure can be achieved by an industrial-grade strain sensor built in the pressure cylinder of the welding machine, the strain sensor is directly integrated on the piston rod of the pressure cylinder to analyze the axial pressure fluctuation in real time.

[0091] Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application, and various changes and improvements can be made without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method of welding a reinforcing mesh for bridge construction, characterized by, The method comprises: applying pre-tension to each of a plurality of first reinforcing bars arranged at a set interval in a first direction, so as to keep the first reinforcing bars in a straight line and fix both ends; placing a plurality of second reinforcing bars arranged at a set interval in a second direction on the first reinforcing bars one by one, to form vertical intersection points; for each of the second reinforcing bars, acquiring actual positions of each of the intersection points by a detection system, and acquiring a gap value between the first reinforcing bar and the second reinforcing bar at the actual position in real time; based on a deviation value between the actual position and a design position, driving a welding gun to perform adaptive displacement compensation in the process of continuously welding each of the intersection points; based on the gap value, dynamically adjusting a welding pressure to complete welding at the compensated position.

2. The reinforcing mesh welding method for bridge construction according to claim 1, characterized by, The method of acquiring actual positions of each of the intersection points by the detection system comprises: acquiring an image of the intersection point area by a visual sensor, and determining a center point coordinate of an overlapping area of the first reinforcing bar and the second reinforcing bar based on an image recognition algorithm, as the actual position of the intersection point.

3. The reinforcing mesh welding method for bridge construction according to claim 2, characterized by, The method of acquiring the gap value between the first reinforcing bar and the second reinforcing bar at the actual position in real time comprises: vertically emitting a laser beam above the center point coordinate to acquire ranging data of the laser beam to the surface of the second reinforcing bar; calculating the gap value based on the ranging data.

4. The reinforcing mesh welding method for bridge construction according to claim 3, characterized by, When the gap value is greater than a set threshold value, the following is performed: re-detecting the gap value after adjusting the position of the second reinforcing bar; if the gap value is less than or equal to the set threshold value, welding is performed; if the gap value is still greater than the set threshold value after N times of adjustment, where N is greater than or equal to 3, the second reinforcing bar is replaced.

5. The reinforcing mesh welding method for bridge construction according to claim 4, characterized by, In the process of repeatedly welding reinforcing mesh of the same type, a probability value of each of the intersection points on each of the second reinforcing bars exceeding the set threshold value is continuously counted; for welding of each of the second reinforcing bars, welding positions are sorted from low to high according to the probability value.

6. The reinforcing mesh welding method for bridge construction according to claim 4, characterized by, The method of adjusting the position of the second reinforcing bar comprises: installing a vibrator at a fixed end of the first reinforcing bar; controlling the vibrator to drive the first reinforcing bar to vibrate, and the vibration frequency is 20 to 50 Hz; displacing the second reinforcing bar in the direction of gravity through contact conduction vibration of the first reinforcing bar and the second reinforcing bar.

7. The reinforcing mesh welding method for bridge construction according to claim 2, characterized by, The method of acquiring actual positions of each of the intersection points comprises: identifying four corner points of the overlapping area of the two reinforcing bars in the image; connecting two pairs of opposite corner points to obtain two straight lines; taking the intersection point of the two straight lines as the center point coordinate of the overlapping area of the first reinforcing bar and the second reinforcing bar.

8. The reinforcing mesh welding method for bridge construction according to claim 1, characterized by, The welding comprises: at the actual position of the intersection point, applying a pre-pressure to the overlapping first reinforcing bar and second reinforcing bar by a double-electrode head of a resistance welding machine, and the pre-pressure is adjusted according to the gap value; in a state of maintaining the pre-pressure, a first current is input, and a contact resistance dynamic value and an electrode pressure fluctuation value are monitored in real time, when the contact resistance dynamic value is less than a first threshold value, and an absolute value of the electrode pressure fluctuation value is less than a second threshold value, a first stage is completed and a second stage is entered; switching to a second current higher than the first current, and synchronously monitoring a dynamic resistance attenuation slope, when the dynamic resistance attenuation slope is less than a third threshold value, the welding is completed by stopping power input.

9. The reinforcing mesh welding method for bridge construction according to claim 8, characterized by, The first current is 40% to 60% of the rated current of the resistance welding machine, and the second current is 70% to 90% of the rated current of the resistance welding machine.

10. The reinforcing mesh welding method for bridge construction according to claim 8, characterized by, The falling rate of the dynamic value of the first-stage contact resistance is recorded, and if the falling rate is less than a fourth threshold value, the corresponding welding spot is marked as a potential false welding spot.

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