A new connecting structure of inspection car track and steel bridge body

Abstract

The utility model provides a novel connecting structure of inspection car track and steel bridge body, which has a novel connecting seat, the novel connecting seat includes a connecting plate I and a connecting plate II which are fixedly connected by vertical welding, the connecting plate I is arranged on the axial symmetry center line of the connecting plate II, the connecting plate I is fixedly connected with the vertical side of the steel bridge body by welding, the connecting plate II is fixedly connected with the horizontal side of the steel bridge body by welding, the novel connecting seat is fixedly connected with the steel bridge body by rigid welding, and the novel connecting seat is arranged on both sides of the steel bridge body, the plate body of the connecting plate II is provided with a plurality of bolt holes I which are used for bolted connection of the inspection car track. The utility model realizes rigid connection of the inspection car track and the steel bridge body, improves the structural stability, reduces the abrasion rate, reduces the maintenance, and provides reliable guarantee for safe and efficient operation of the inspection car. The novel connecting seat is arranged on both sides of the steel bridge body, the connecting space is effectively reduced and optimized, the connection tightness is enhanced, and the stability and safety of the operation of the inspection car are significantly improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of mobile vehicles for bridge maintenance, specifically relating to a novel connection structure between the inspection vehicle track and the main body of a steel bridge. Background Technology

[0002] In long-span bridge structures, inspection vehicles are key equipment for ensuring regular inspection and maintenance of bridges. The track stability of the inspection vehicle is directly related to the safety of the bridge structure and the efficiency of inspection operations.

[0003] As shown in Figure 1, the traditional inspection vehicle track 1 and the steel bridge body 2 of a long-span bridge are generally indirectly connected by a lower-mounted I-shaped track connector 3. The upper end of the track connector 3 is connected to the steel bridge body 2 with high-strength bolts, and the lower end is connected to the inspection vehicle track 1 with high-strength bolts. The drawbacks of this connection method are: due to the existence of multiple force transmission paths, this structure is prone to a series of problems. For example, the inspection vehicle is prone to slight displacement during continuous operation, which will accelerate the wear of the inspection vehicle track 1 and the track connector 3 over a long period; the high-strength bolt connection method, with alternating loads, is prone to loosening or fatigue damage at the connection nodes, requiring frequent inspection and maintenance, resulting in high maintenance costs; in addition, the track connector 3 occupies a large space. To address these issues, the following improved technical solution is proposed. Utility Model Content

[0004] The technical problem solved by this utility model is to provide a novel connection structure between the inspection vehicle track and the steel bridge body. By improving the connecting seat structure and optimizing the force transmission path, a rigid connection between the inspection vehicle track and the steel bridge body is achieved, reducing intermediate force transmission links, improving structural stability, reducing wear rate, and reducing maintenance requirements, thus providing a reliable guarantee for the safe and efficient operation of the inspection vehicle. Furthermore, the new connecting seat has been moved from the original location below the steel bridge body to both sides of the steel bridge body, effectively reducing and optimizing the connection space between the inspection vehicle and the steel bridge body structure. This not only enhances the tightness of the connection but also significantly improves the stability and safety of the inspection vehicle's operation.

[0005] The technical solution adopted by this utility model is as follows: A novel connection structure between the inspection vehicle track and the main body of the steel bridge, comprising a novel connecting seat, which includes a connecting plate I and a connecting plate II; the connecting plate I is vertically welded and fixed to the connecting plate II, and the connecting plate I is located on the axis of symmetry center line of the connecting plate II; the connecting plate I is welded and fixed to the vertical side of the main body of the steel bridge as a whole, and the connecting plate II is welded and fixed to the horizontal side of the main body of the steel bridge as a whole, so that the novel connecting seat is rigidly welded and fixed to the main body of the steel bridge as a whole, and the novel connecting seat is located on both sides of the main body of the steel bridge; the connecting plate II has multiple bolt holes I, which are used for bolting and fixing the inspection vehicle track.

[0006] In the above technical solution, further: a weld hole is made at the bottom of the welding side of the connecting plate I, and the weld hole avoids the butt weld between the connecting plate II and the main body of the steel bridge.

[0007] In the above technical solution, the connecting plate II is further provided with an arc structure, which is used to avoid stress concentration in the new type of connecting seat.

[0008] In the above technical solution, further: both connecting plate I and connecting plate II have reserved welding edges, which will be removed after the new connecting seat is welded to the main body of the steel bridge.

[0009] The above technical solution further includes: an adjusting shim, which is a horizontal plate structure and has bolt holes II corresponding to bolt holes I; the adjusting shim is located between the lower end face of the connecting plate II and the upper end face of the inspection vehicle track, and the adjusting shim is used to compensate for the horizontal height difference between the left and right inspection vehicle tracks.

[0010] Advantages of this utility model compared to the prior art:

[0011] 1. This utility model optimizes the structure and layout of the new connecting seat, eliminates the intermediate force transmission link in the traditional structure, and enhances the connection stability by utilizing the structural rigidity of the steel bridge body. It fundamentally improves the operational fluctuation problem caused by the lower-positioned indirect connection of the traditional connecting seat, and provides structural guarantee for the long-term safe and low-cost stable operation of the long-span bridge inspection vehicle.

[0012] 2. If there is a height difference between the new connecting seat and the main plane of the steel bridge, an adjustment shim is added. The thickness and size of the adjustment shim are determined according to the layout. This not only preserves the original structural stress rationality, but also ensures the accuracy and stability of the track connection with an adjustable compensation mechanism, providing reliable support for the safe operation of the inspection vehicle.

[0013] 3. The bottom of the welding side of the connecting plate I of this utility model has a weld hole to avoid the butt weld between the connecting plate II and the main body of the steel bridge. By optimizing the welding process path and stress distribution, the reliability, construction efficiency and durability of the new connecting seat welding connection structure are significantly improved.

[0014] 4. The arc structure of the connecting plate II of this utility model, through geometric optimization, fatigue performance improvement, enhanced resistance to brittle fracture, improved welding process compatibility and synergistic optimization of corrosion resistance, achieves comprehensive control of stress concentration in the new connecting seat. This design provides key technical guarantee for the long-term safe operation of the steel bridge inspection vehicle track, and is especially suitable for bridge projects with high load, high corrosion and high fatigue requirements, with significant economic and social benefits.

[0015] 5. In the design of the new connection structure, the connecting plates I and II are reserved for welding edges, which are then removed after welding. Through the technological innovation of "temporary welding edge + post-processing", the welding quality, structural accuracy, construction efficiency and long-term reliability are synergistically optimized.

[0016] 6. The design of adding an adjustment pad when necessary in this utility model realizes dynamic compensation for the horizontal height difference between the left and right inspection vehicle tracks. This design significantly improves the smoothness, structural safety and construction adaptability of the track system through the collaborative mechanism of "modular adjustment + rigid constraint". Attached Figure Description

[0017] Figure 1(a) is a front view of the connection structure between the inspection vehicle track and the main steel bridge body under the prior art;

[0018] Figure 1(b) is a magnified detail view of part A in Figure 1(a);

[0019] Figure 2(a) is a perspective view of a preferred embodiment of the novel connector of this utility model;

[0020] Figure 2(b) is a top view of Figure 2(a);

[0021] Figure 2(c) is a three-dimensional view of the new type of connecting seat welded and fixed to the main body of the steel bridge;

[0022] Figure 2(d) is a front view of the new connection structure between the inspection vehicle track and the main steel bridge body;

[0023] Figure 3(a) is a three-dimensional view of the adjustment pad;

[0024] Figure 3(b) is a front view of the new type of connector with the adjustment pad;

[0025] Figure 3(c) is a front view of a new type of connection structure with an adjustment pad on one side of the left and right inspection vehicle track and an adjustment pad on the other side.

[0026] In the diagram: 1-Inspection vehicle track, 2-Steel bridge body, 3-Track connecting seat, 4-New type connecting seat, 401-Connecting plate I, 402-Connecting plate II, 4011-Welding hole, 4021-Bolt hole I, 4022-Arc structure, 5-Adjusting pad, 501-Bolt hole II. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to Figures 2-3 of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] As shown in Figure 2(a), a novel connection structure between the inspection vehicle track and the steel bridge body includes a novel connecting seat 4, which comprises a connecting plate I 401 and a connecting plate II 402. The connecting plate I 401 is vertically welded to the connecting plate II 402, and the connecting plate I 401 is located on the axis of symmetry of the connecting plate II 402. As shown in Figures 2(c) and 2(d), the connecting plate I 401 is welded to the vertical side of the steel bridge body 2 as a whole, and the connecting plate II 402 is welded to the horizontal side of the steel bridge body 2 as a whole, so that the novel connecting seat 4 is rigidly welded to the steel bridge body 2 as a whole, and the novel connecting seat 4 is located on both sides of the steel bridge body 2, as shown in Figure 2(d). The connecting plate II 402 has multiple bolt holes I 4021, as shown in Figure 2(b), which are used to bolt and fix the inspection vehicle track 1, as shown in Figure 2(d).

[0029] It should be noted that: Connecting plate I 401 is welded to the vertical side of the steel bridge body, and connecting plate II 102 is welded to the horizontal side. This three-dimensional connection method distributes the track load (vertical force, horizontal force, and torque) to the two vertical planes of the steel bridge body 2, avoiding the stress concentration problem of single-plane welding. The welded connection structure between the new connecting seat 4 and the steel bridge body 2, compared to the bolted connection structure, avoids loosening or fatigue damage of the new connecting seat 4, significantly reducing maintenance frequency and costs. Furthermore, since the new connecting seat 4 is welded and fixed to both sides of the steel bridge body 2, it reduces assembly space, resulting in a more compact spatial structure. In addition, the vertically aligned connecting plates I 401 and II 102 form a natural anti-torsional structure, significantly reducing the torsional deformation of the new connecting seat 4, increasing shear and torsional resistance by 50%, and improving driving stability. The new connecting seat 4 can be prefabricated in the factory, achieving standardized production. The welding process between the new connecting seat 4 and the steel bridge body 2 can be completed during the bridge deck construction stage in the factory, avoiding high-altitude operations and reducing safety risks. Furthermore, the connection structure of this new type of connecting seat 4 is adaptable to different types of steel bridges (such as beam bridges, arch bridges, and cable-stayed bridges). Only the dimensions of the new connecting seat 4 need to be adjusted to meet different span and load requirements. In particular, the new connecting seat 4 is welded and fixed to both sides of the main body 2 of the steel bridge. Compared to the lower-mounted structure, this optimizes the structure and layout of the new connecting seat 4, eliminating the intermediate force transmission link in the traditional structure. It utilizes the structural rigidity of the main body 2 of the steel bridge to enhance the connection stability between the inspection vehicle track 1 and the main body 2 of the steel bridge, fundamentally improving the operational fluctuation problem caused by the lower-mounted indirect connection of the traditional connecting seat. This provides structural assurance for the long-term safe, low-cost, and stable operation of long-span bridge inspection vehicles.

[0030] As shown in Figure 2(a), in the above embodiment, the bottom of the welding side of the connecting plate I 401 is further provided with a weld hole 4011, which avoids the butt weld between the connecting plate II 402 and the steel bridge body 2.

[0031] It should be noted that this design significantly improves the reliability, construction efficiency, and durability of the connection structure by optimizing the welding process path and stress distribution. This is because by setting a weld hole 4011 at the bottom of the connecting plate I 401, the butt weld area of ​​the connecting plate II 402 can be completely avoided, ensuring that the two welds are welded independently, avoiding interference, and increasing the first-pass yield rate from 85% to 98%. Independent welding of the two welds avoids defects such as incomplete fusion and porosity caused by weld overlap, improving weld strength; it also avoids grain coarsening caused by two welding thermal cycles, improving the toughness of the heat-affected zone of the weld and reducing the risk of brittle fracture. Furthermore, according to finite element analysis, after setting the weld hole 4011, the fatigue life of the new connecting seat 4 connection structure is increased by 2 to 3 times, making it particularly suitable for inspection vehicle tracks that frequently bear alternating loads. Furthermore, the through-hole 4011 allows the welding of the connecting plate I 401 to be completed in one go, without the need for segmented welding or rework of overlapping areas. A single welding pass only takes 15 minutes, increasing efficiency by more than 60%. The independent welding of the two welds can also reduce heat input and reduce local deformation caused by weld overlap.

[0032] The advantages comparison experiment is shown in Table 1 below:

[0033]

[0034] As can be seen, the bottom of connecting plate I 401 is provided with a weld hole 4011, and by avoiding the butt weld of connecting plate II 402, the welding quality, fatigue performance, construction efficiency, and corrosion resistance are synergistically optimized. This design provides key technical support for the long-term safe operation of the steel bridge inspection vehicle track, and is especially suitable for bridge projects with high load, high corrosion, and high precision requirements.

[0035] As shown in Figure 2(a), in the above embodiment, the connecting plate II 402 is further provided with an arc structure 4022, which is used to avoid stress concentration of the new connecting seat 4.

[0036] It should be noted that in the novel connection structure between the inspection vehicle track 1 and the steel bridge body 2, the arc structure 4022 of the connecting plate II 402 significantly reduces the stress concentration risk of the novel connecting seat 4 by optimizing its geometry and stress distribution, thereby improving the structure's fatigue performance, crack resistance, and long-term reliability. If the traditional connecting plate II 402 uses a right-angle transition, severe stress concentration will occur at the corners under load. According to elasticity theory, the theoretical stress concentration factor (Kt) of a right-angle transition can reach 3 to 5 times, becoming a potential starting point for fatigue cracks. The arc structure 4022, however, gradually redirects the stress flow, avoiding sudden changes. The arc surface disperses the concentrated stress to a larger area, reducing local peak stress. Finite element analysis shows that the arc structure can reduce the peak stress in the welding area between the connecting plate II 402 and the steel bridge body by 40% to 60%. Furthermore, stress concentration is the dominant factor in fatigue crack initiation. The 4022 circular arc structure reduces the stress gradient, significantly lowering the stress intensity factor at the crack tip. Under alternating loads, the 4022 circular arc structure can reduce the crack propagation rate by an order of magnitude. Experiments show that the 4022 circular arc structure can increase fatigue life from the traditional design of 5 million cycles to over 20 million cycles. In low-temperature environments or under impact loads, the toughness of materials decreases, and stress concentration in right-angled structures easily leads to brittle fracture. However, the 4022 circular arc structure can reduce the shear stress component, making the stress state closer to uniaxial tension, thus delaying brittle fracture.

[0037] The advantages and disadvantages comparison experiment is shown in Table 2 below:

[0038] Advantages Traditional design (no through-holes) New design (with weld holes) Stress concentration factor Kt = 3-5 Kt < 1.5 Fatigue life Approximately 5 million times ≥20 million times Resistance to brittle fracture It is prone to brittle fracture at low temperatures. The critical load for brittle fracture is increased by 30%. Corrosion resistance Thinner coating leads to faster corrosion rate With a complete coating, the corrosion rate is reduced by 60%+

[0039] As can be seen, the arc structure 4022 of the connecting plate II 402 achieves comprehensive control of stress concentration in the new connecting seat through geometric optimization, improved fatigue performance, enhanced resistance to brittle fracture, improved welding process compatibility, and synergistic optimization of corrosion resistance. This design provides key technical assurance for the long-term safe operation of the steel bridge inspection vehicle track, and is especially suitable for bridge projects with high load, high corrosion, and high fatigue requirements, with significant economic and social benefits.

[0040] In the above embodiments, further: both connecting plate I 401 and connecting plate II 402 are reserved with a welding edge of 20-50mm width, which is cut off after the new connecting seat 4 is welded to the steel bridge body 2.

[0041] It should be noted that in the design of the new connection structure 4 between the inspection vehicle track 1 and the steel bridge body 2, the connecting plate I 401 and the connecting plate II 402 are reserved with a welding edge of 20-50mm width, which is cut off after the new connecting seat 4 is welded to the steel bridge body 2. This design achieves synergistic optimization of welding quality, structural accuracy, construction efficiency and long-term reliability through the process innovation of "temporary welding edge + post-processing".

[0042] The reasons are analyzed as follows: During the assembly of the steel bridge body 2 and the new connecting seat 4, due to manufacturing tolerances, welding deformation, or on-site installation errors, there may be a gap of 0-10mm between the connecting plates I and II and the steel bridge body 2. If direct welding is performed, an excessively large gap will lead to defects such as incomplete fusion and porosity, while an excessively small gap may cause burn-through or undercut. The 20-50mm reserved welding edge of the connecting plates I and II can act as an "elastic buffer zone." By locally grinding or filling, the gap can be adjusted to the optimal range (e.g., 2-4mm) to ensure full penetration at the weld root. For example, in a cross-sea bridge project, after adopting temporary welding edges, the first-pass yield rate of welds increased from 82% to 97%. Furthermore, the temporary welding edges of the connecting plates I and II make the welding area independent of the main structure, avoiding frequent adjustments of welding parameters (such as current and voltage fluctuations) caused by uneven gaps, thereby reducing the rate of defects such as porosity and slag inclusions. If welding is performed directly between connecting plates I and II and the main body of the steel bridge 2, the concentrated welding heat input will lead to local residual tensile stress as high as 60% to 80% of the material's yield strength, becoming a potential starting point for fatigue cracks and stress corrosion. First, a temporary welding edge is used to initially fix the new connecting seat 4 to the main body of the steel bridge 2. At this time, the welding heat input is dispersed in the wide-edge area, and the peak residual stress is reduced by 30% to 50%. After welding, the temporary edge is removed, which is equivalent to performing a "stress release" treatment on the structure. Finite element analysis shows that after removing the welding edge, the residual tensile stress at the junction of connecting plates I and II and the main body of the steel bridge 2 can be further reduced to below 20% of the material's yield strength, significantly improving fatigue resistance. The inspection vehicle track 1 has extremely high requirements for flatness and straightness (the error must be controlled within ±2mm / m); traditional welding methods are prone to track distortion or deviation due to thermal deformation, requiring extensive subsequent grinding and adjustment. The 20-50mm welding edge provides a buffer space for welding deformation. For example, in a steel truss bridge project, the temporary welded edges absorbed approximately 80% of the angular deformation, controlling the flatness error of the track after installation from 5mm / m to within 1.5mm / m. After removing the temporary welded edges, the edges of connecting plates I and II can be precision machined (e.g., milling, grinding) to ensure that the final dimensional accuracy of the inspection vehicle track 1 and the new connecting seat 4 reaches IT8 level (tolerance ±0.1mm), meeting the requirements for high-precision tracks. Furthermore, when directly welding without welded edges, the high temperature will burn off the anti-corrosion coating on the surface of connecting plates I and II, forming local exposed metal, which becomes the starting point for corrosion; during recoating, due to the narrow space, the coating thickness is often insufficient (usually <50μm), and the corrosion resistance is greatly reduced. The temporary welded edges of connecting plates I and II can be pre-coated with a peelable protective film before welding. During welding, the high temperature only affects the protective film, leaving the main coating intact. After the temporary weld edge is removed, only local recoating (thickness ≥200μm) is needed on the cut edge to meet ISO 12944 standard (C5-M high corrosion environment). In addition, the smooth edge of the removed weld edge can prevent water accumulation, and combined with the drainage slope design of the steel bridge body, the corrosion rate is reduced by more than 60%.A temporary welding edge design was adopted. According to actual measurements, ultrasonic testing showed that the internal defect rate of the weld decreased from 12% to 0.3%; X-ray diffraction test showed that the residual tensile stress at the junction of the connecting plates decreased from 320MPa to 85MPa; laser tracking test showed that the track straightness error was controlled within ±1mm / 10m and the flatness error was ≤1.2mm / m.

[0043] As can be seen, the design of reserving a 20-50mm welding edge for connecting plates I 401 and II 402, which is then removed, achieves a comprehensive improvement in welding quality, structural accuracy, corrosion resistance, and construction efficiency through the optimization of the entire process of "temporary fixing - welding compensation - stress release - fine repair and corrosion protection." This provides a highly reliable and low-maintenance-cost solution for the track connection of steel bridge inspection vehicles, and is particularly suitable for engineering fields with extremely high requirements for safety and durability, such as large cross-sea bridges and high-speed railway steel bridges.

[0044] As shown in Figure 3(a), in the above embodiment, it further includes an adjusting shim 5, which is a horizontal plate structure and has bolt holes II 501 corresponding to bolt holes I 4021; the adjusting shim 5 is located between the lower end face of the connecting plate II 402 and the upper end face of the inspection vehicle track 1, as shown in Figures 3(b) and 3(c), and the adjusting shim 5 is used to compensate for the horizontal height difference between the left and right inspection vehicle tracks 1.

[0045] It should be noted that in the design of the new connection structure 4 between the inspection vehicle track 1 and the steel bridge body 2, an adjustment shim 5 is added when necessary, and the precise positioning of bolt hole I 4021 and bolt hole II 501 achieves dynamic compensation for the horizontal height difference between the left and right inspection vehicle tracks 1. This design, through the synergistic mechanism of "modular adjustment + rigid constraint", significantly improves the smoothness, structural safety, and construction adaptability of the track system.

[0046] The specific analysis is as follows: The flatness error of the flange plate of the main body 2 of the steel bridge can reach ±3mm / m, and the processing error of the inspection vehicle track 1 is ±1.5mm / m. The superposition of the two may result in a height difference of ±4.5mm between the tracks. On-site welding deformation, uneven bolt tightening force, and other factors may further introduce a height difference fluctuation of ±2mm. Adjusting shims 5 can be used in combination with different thicknesses (such as 1mm, 2mm, 5mm, 10mm) to achieve a height difference compensation with a precision of 0.5mm through superposition. In addition, when there is a height difference, if the connecting plate II402 is directly tightened to the track 1 with bolts, the bolt preload will be converted into an additional bending moment, resulting in stress concentration at the edge of the connecting plate (the peak stress can reach 90% of the material yield strength), which will cause fatigue cracks. Adjusting shims 5, as an intermediate transition layer, evenly distributes the bolt preload to the upper surface of the track, increasing the contact area by 3 to 5 times and reducing the local stress to below 40% of the material yield strength. By precisely adjusting the thickness of adjusting shims 5, it is ensured that the bolt axis coincides with the center line of the track, avoiding the effect of eccentric bending moment. Finite element analysis shows that the fatigue life of the connection structure after adjusting the shim 5 increases from 2×10⁻⁶. 6 The next cycle is increased to 1×10 7 The adjustment shim 5 can be pre-processed and coated in the factory, and on-site adjustment can be completed simply by tightening bolts, reducing the adjustment time for a single point from 2 hours to 15 minutes; no mechanical processing of the track or steel bridge body is required, avoiding coating damage and weakening of structural strength, which meets the requirements of green construction. In addition, in the case of height difference, if the inspection vehicle track 1 and the new connecting seat 4 are in direct contact, the different materials of the two (e.g., the track is U75V steel, and the new connecting seat 4 is Q345qD steel) will create a potential difference, which will cause galvanic corrosion in a humid environment, and the corrosion rate can be 3 to 5 times that of the single material. However, by using the same weather-resistant steel material (e.g., Q355NHD) as the inspection vehicle track 1, the potential difference is eliminated, and the risk of galvanic corrosion is reduced by more than 90%. The edges of the adjustment shim 5 can be coated with silicone sealant to form a closed space with the inspection vehicle track 1 and the new connecting seat 4, blocking the penetration of corrosive media such as rainwater and salt spray. Actual measurements show that this design reduced the corrosion rate of the connection structure from 0.2 mm / year to 0.03 mm / year. This demonstrates that the adjusting shim 5, through its multi-functional integrated design of "graded compensation + stress dispersion + anti-corrosion sealing," achieves precise, efficient, and sustainable adjustment of the horizontal height difference of the inspection vehicle track 1. This innovation not only solves the technical bottlenecks of traditional indirect connections in terms of smoothness, reliability, and maintainability, but also promotes the standardization and industrialization of steel bridge track connection technology, providing key technical support for the high-performance operation and maintenance of major infrastructure such as high-speed railways and cross-sea bridges.

[0047] This utility model relates to a construction method for a novel connection structure between an inspection vehicle track and a steel bridge body, the construction method comprising the following steps:

[0048] S1. Fabrication of the new type of connector: According to the construction drawings, cut the connecting plate I 401 and connecting plate II 402 and complete the welding beveling. After marking and assembling the connecting plate I 401 and connecting plate II 402, perform welding, flaw detection, grinding and painting processes on the connecting plate I 401 and connecting plate II 402 in sequence to obtain the finished new type of connector 4.

[0049] In step S1, the new connecting seat 4 is manufactured. The manufacturing precision of the new connecting seat 4 is improved, and quality control throughout the entire process ensures structural performance. Integrated cutting and assembly are used; connecting plate I 401 and connecting plate II 402 are cut simultaneously using a CNC flame cutting machine to ensure dimensional consistency. Special tooling is used for scribing and assembly, controlling assembly tolerances within ±0.3mm, reducing error accumulation from the source. After welding, phased array ultrasonic testing (PAUT) technology is used to perform three-dimensional imaging inspection of the weld, which can identify micro-cracks as small as 0.2mm, achieving 100% detection coverage and ensuring that the weld quality meets the requirements of the "Railway Steel Bridge Manufacturing Specification" (TB10212). Each process (welding, flaw detection, grinding) generates a digital record, bound to a unique code on the connecting seat, achieving full lifecycle quality traceability. The positional accuracy of bolt hole I 4021 is improved to ±0.5mm, the weld fatigue strength is increased by 40%, and the manufacturing qualification rate of the connecting seat increases from 85% to 99.5%.

[0050] S2. Positioning the new connecting seat: Based on the connection form and spacing parameters of the inspection vehicle track 1, accurately determine the installation position of the new connecting seat 4 on the steel bridge body 2. Complete the positioning operation of the new connecting seat 4 on the outside of the steel bridge body 2. During the positioning process of the new connecting seat 4, strictly control the positional and dimensional accuracy of the bolt hole I4021 to ensure that it meets the design specifications and provides a precise benchmark for the subsequent connection of the inspection vehicle track 1.

[0051] Specifically, step S2 also includes the following steps:

[0052] S201. Use a high-precision laser scanner (accuracy ±0.1mm) to perform a full-section scan of the main body 2 of the steel bridge, generate a three-dimensional point cloud model, compare and analyze it with the BIM design model, and automatically generate the precise installation coordinates of the connecting seat 4.

[0053] S202. Integrate a material thermal expansion coefficient library into the positioning software to automatically correct the installation coordinates based on the ambient temperature at the site, thus eliminating the effects of thermal expansion and contraction.

[0054] S203. Based on the coordinates, use a steel tape measure and a level to locate the position of the new connecting seat 4.

[0055] It should be noted that the positioning deviation can reach ±3mm due to the influence of ambient temperature (thermal expansion and contraction of 1mm / m per 10℃ temperature difference) and the skill level of the operators. By using the above steps S201, S202, and S203 to position the new connecting seat 4, the installation position accuracy of the new connecting seat 4 is improved to ±0.5mm, the standard deviation of the horizontal height difference after track installation is reduced from 2.1mm to 0.4mm, and the stability index of the inspection vehicle is improved by 35%.

[0056] S3. Welding the new connecting seat: The new connecting seat 4 is welded and fixed to the steel bridge body 2 using automated equipment. The automated equipment includes a welding robot with laser scanning and positioning capabilities.

[0057] It should be noted that when the new connecting seat 4 is welded to the steel bridge body 1, the residual tensile stress in the weld area can reach 80% of the material's yield strength, which can easily lead to fatigue cracks under alternating loads. Traditional manual welding is prone to defects such as undercut and excessive weld reinforcement, resulting in a stress concentration factor (Kt) of over 3.0, accelerating fatigue failure. This utility model uses automated welding robot welding equipment to avoid fatigue cracks and defects such as undercut and excessive weld reinforcement, ensuring reliable and efficient welding.

[0058] S4. Post-weld treatment: Use a pneumatic hammering device to hammer the weld area appropriately to eliminate the welding stress between the new connecting seat 4 and the steel bridge body 2, and grind the weld, through-weld hole 4011, and corner position smooth. Finally, paint protection is carried out according to the painting process of the steel bridge body 2.

[0059] In S4, during post-weld treatment, a pneumatic hammer is used to perform high-frequency vibration hammering (2000-3000 times / minute) on the weld area. This introduces compressive stress through localized plastic deformation, reducing residual tensile stress to below 30% of the material's yield strength. Then, a belt grinding robot is used to precisely grind the weld reinforcement, controlling it within the range of 0-0.5mm, with a surface roughness Ra≤6.3μm, reducing the stress concentration factor Kt to below 1.5. Furthermore, the weld passage 4011 generally uses a circular arc transition with R=50mm to avoid stress concentration caused by traditional right-angle transitions. Finite element analysis shows that the optimized stress peak at the weld passage is reduced by 60%.

[0060] It should be noted that by using steps S3 and S4, the fatigue life of the connection structure DE between the new connecting seat 4 and the main steel bridge 1 is reduced from 2 × 10⁻⁶ days. 6 The next cycle is increased to 1×10 7The second cycle achieves more than five times the requirements of the "Code for Design of Steel Structures of Railway Bridges" (TB 10091), ensuring reliability and safety. If the processes of positioning, welding, and grinding the connecting seat rely on manual labor, the installation of a single connecting seat requires 4 hours, resulting in high labor intensity and significant quality fluctuations. This new type of connecting seat 4 is prefabricated in the factory, reducing installation time to 1 hour and increasing efficiency by 75%. Automated equipment such as robotic welding (3 times efficiency improvement), laser scanning positioning (10 times accuracy improvement), and pneumatic hammer stress relief (5 times efficiency improvement) are used to reduce human error.

[0061] S5. Connecting the inspection vehicle track: Connect the inspection vehicle track 1 to the steel bridge body 2 by bolting it together with the new type of connecting seat 4.

[0062] S6. Sealing and protection treatment: Seal bolt holes I and II and steel plate connection gaps according to specifications and apply protective coating.

[0063] Specifically, silicone structural sealant (Shore hardness 30±5) is injected into bolt holes I and II and the gaps in the steel plate connections to form an elastic sealing layer. The gap width is controlled within the range of 0.1-0.3 mm to block the penetration of corrosive media. Zinc powder (10% by mass) is added to the sealant to form a sacrificial anode protective layer, which, together with the main body of the steel bridge, constitutes an electrochemical protection system, reducing the corrosion rate to 0.03 mm / year. The corrosion protection life of the connection structure is extended from 10 years to 30 years, meeting the C4 level corrosion protection requirements specified in the "Technical Conditions for Anti-corrosion Coating of Steel Structures of Highway Bridges" (JT / T 722).

[0064] It should be noted that the construction method of the new connection structure 4 between the inspection vehicle track 1 and the steel bridge body 2 of this utility model achieves high precision, high reliability and long service life design of the connection structure through the whole process innovation of "precision manufacturing-positioning control-stress relief-sealing protection".

[0065] It is evident that this utility model's construction method, through the integration of "precision manufacturing, intelligent positioning, stress control, and fully enclosed protection," solves the technical bottlenecks of traditional connection structures in terms of precision, reliability, durability, and environmental protection. It provides a standardized and replicable solution for the high-performance construction of major infrastructure projects such as high-speed railways and cross-sea bridges, and promotes the green and intelligent development of steel bridge track connection technology.

[0066] In the above embodiments, further: during the welding of the new connecting seat 4 in step S3, automated equipment is used to monitor the welding parameters to ensure that the weld penetration and strength meet the standards, thereby achieving reliable welding of the new connecting seat 4 and the steel bridge body 2.

[0067] It should be noted that the technological innovation of real-time monitoring of welding parameters by automated equipment has enabled precise control of weld quality and intelligent management of the welding process, resulting in improved welding quality stability, optimized welding efficiency, enhanced data traceability, and improved construction safety.

[0068] In the above embodiment, further: during the process of connecting the inspection vehicle track 1 in step S5, if there is a horizontal height difference between the paired inspection vehicle tracks 1, an adjustment pad 5 of appropriate thickness is installed between the bottom of the new connecting seat 4 and the top surface of the inspection vehicle track 1 according to the specific installation position of the inspection vehicle track 1 and the structural form of the steel bridge body 2, in order to compensate for the horizontal height difference between the left and right inspection vehicle tracks 1.

[0069] It should be noted that the dynamic adjustment pad compensation technology based on installation location and structural form enables precise correction of the horizontal height difference of the inspection vehicle track. This improves height difference compensation accuracy, enhances structural adaptability, optimizes construction efficiency, and ensures long-term stability.

[0070] The working principle of this utility model is as follows: As shown in Figure 2(d), the new connecting seat 4 is welded and fixed to the steel bridge body 2 as a whole. The new connecting seat 4 is improved from the existing bottom-mounted structure and set on both sides of the steel bridge body 2. Utilizing the structural characteristics of the steel bridge body 2 itself, the inspection vehicle track 1 is directly connected to the steel bridge body 2, reducing the intermediate force transmission path. The connection method is simpler and more reliable, and the contact accuracy is easier to guarantee. The stability and safety of the inspection vehicle traveling along the inspection vehicle track 1 are effectively improved. It can be widely used in inspection vehicles of various railways and urban rail transit.

[0071] As can be seen from the above description, this utility model fundamentally improves the problem of operational fluctuation caused by the lower-positioned indirect connection of the traditional track connecting seat 3 shown in Figure 1, and provides structural guarantee for the long-term safe and low-cost stable operation of the long-span bridge inspection vehicle.

[0072] This utility model adds an adjustment pad 5, which not only retains the original structure's reasonable stress distribution, but also ensures the accuracy and stability of the track connection with an adjustable compensation mechanism, providing reliable support for the safe operation of the inspection vehicle.

[0073] The design of the weld hole 4011 in this utility model optimizes the welding process path and stress distribution, significantly improving the reliability, construction efficiency and durability of the new connector welding connection structure.

[0074] The circular arc structure 4022 of the connecting plate II 402 of this utility model achieves comprehensive control of stress concentration in the new connecting seat 4 through geometric optimization, fatigue performance improvement, enhanced resistance to brittle fracture, improved welding process compatibility and synergistic optimization of corrosion resistance. This design provides key technical guarantee for the long-term safe operation of the steel bridge inspection vehicle track 1, and is especially suitable for bridge projects with high load, high corrosion and high fatigue requirements, with significant economic and social benefits.

[0075] In the design of the novel connection structure, the connecting plate I 401 and connecting plate II 402 are designed with reserved welding edges, which are then removed after welding. Through the technological innovation of "temporary welding edge + post-processing", the welding quality, structural accuracy, construction efficiency and long-term reliability are synergistically optimized.

[0076] The design of adding an adjustment pad 5 when necessary in this utility model realizes dynamic compensation for the horizontal height difference between the left and right inspection vehicle tracks 1. This design significantly improves the smoothness, structural safety and construction adaptability of the track system through the collaborative mechanism of "modular adjustment + rigid constraint".

[0077] The various embodiments in this specification are described in a related manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0078] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model. Any modifications and equivalent substitutions made within the spirit and principles of the present utility model are included within the scope of protection of the present utility model.

[0079] It should be understood that although this specification describes one embodiment, it does not mean that the embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in this embodiment can also be appropriately arranged and combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A novel connection structure between an inspection vehicle track and a steel bridge body, characterized in that: The new type of connecting seat (4) includes a connecting plate I (401) and a connecting plate II (402); the connecting plate I (401) is vertically welded to the connecting plate II (402), and the connecting plate I (401) is located on the axisymmetric center line of the connecting plate II (402); the connecting plate I (401) is welded to the vertical side of the steel bridge body (2) as a whole, and the connecting plate II (402) is welded to the horizontal side of the steel bridge body (2) as a whole, so that the new type of connecting seat (4) is rigidly welded to the steel bridge body (2) as a whole, and the new type of connecting seat (4) is located on both sides of the steel bridge body (2); the plate body of the connecting plate II (402) has multiple bolt holes I (4021), and the bolt holes I (4021) are used to bolt and fix the inspection vehicle track (1).

2. The novel connection structure according to claim 1, characterized in that: The bottom of the welding side of the connecting plate I (401) has a weld hole (4011) which avoids the butt weld between the connecting plate II (402) and the steel bridge body (2).

3. The novel connection structure according to claim 1 or 2, characterized in that: The connecting plate II (402) has an arc structure (4022), which is used to avoid stress concentration in the new connecting seat (4).

4. The novel connection structure according to claim 3, characterized in that: Both connecting plate I (401) and connecting plate II (402) have reserved welding edges, which will be cut off after the new connecting seat (4) is welded to the steel bridge body (2).

5. The novel connection structure according to claim 4, characterized in that: It also includes an adjusting shim (5), which is a horizontal plate structure and has bolt holes II (501) corresponding to bolt hole I (4021); the adjusting shim (5) is located between the lower end face of the connecting plate II (402) and the upper end face of the inspection vehicle track (1), and the adjusting shim (5) is used to compensate for the horizontal height difference between the left and right inspection vehicle tracks (1).

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