A three-catenary steel truss girder built-in gantry bridge deck panel mounting device and construction method

Abstract

This invention discloses an installation device and construction method for a three-truss steel girder with an internal gantry crane panel. The invention includes a steel truss girder body, a track installation assembly mounted on the surface of the steel truss girder body, a gantry assembly mounted on the surface of the steel truss girder body, and a mobile power supply assembly mounted on the surface of the steel truss girder body. The gantry assembly includes a fixed rod fixedly connected to the surface of a support plate. A crane is movably connected inside the moving slot. The crane moves and lifts the precast panels within the entire three-truss steel truss girder. After the precast panels are transported to the bridge site, they are lifted and fed to the installed gantry crane. The gantry crane then uses a lifting line to lift the precast panels and move them along the gantry crane track. With the assistance of manual labor, the precast panels are moved to the designed installation position, i.e., the placement slot is precisely aligned. Throughout the construction process, the gantry crane operates smoothly and flexibly, solving the problems of crane overturning and low installation accuracy that are common in traditional paving methods using cranes.

Description

Technical Field

[0001] This invention relates to the technical field of precast bridge deck installation equipment for cast-in-place three-truss steel girders, specifically to a three-truss steel girder built-in gantry crane bridge deck installation device and construction method. Background Technology

[0002] Steel trusses, due to the numerous advantages of steel, such as high strength, uniform material, good plasticity and toughness, and good weldability, require steel for use in steel bridges. These steels must possess not only high strength but also good plasticity. For steel bridges operating at low temperatures, good low-temperature impact toughness is required; for welded steel bridges, weldability is essential. Plasticity is a safety indicator for steel structures because at points of localized stress concentration in bridge structures, where residual welding stress exists, the stress value may exceed the yield point. Steel with good plasticity can redistribute stress through plastic deformation, preventing localized structural failure that could lead to the failure of the entire structure. Steel with poor toughness is prone to brittle fracture under adverse conditions such as low temperatures or rapid loading. Therefore, low-temperature impact toughness is commonly used to assess the brittle fracture tendency of steel. As steel ages and its toughness decreases with service life, there are also requirements for aging impact toughness. The steel used in modern steel bridges must also possess good weldability, enabling the formation of high-quality welded joints through specific welding processes.

[0003] Patent No. CN202110482269.8 relates to the field of cable tray testing technology, and discloses a compressive strength testing device for cable tray production. The device includes a support platform, with support rods fixedly connected to the four corners of the top of the support platform. A fixed horizontal plate is fixedly connected between the tops of the four support rods. A first fixed vertical plate and a second fixed vertical plate are fixedly connected to the bottom sides of the fixed horizontal plate, respectively. A one-way threaded rod is rotatably installed between the first and second fixed vertical plates. A first rotary motor is fixedly installed on the side of the first fixed vertical plate away from the second fixed vertical plate. This invention has an ingenious structure and is easy to use. It can clamp and fix the cable tray steel bars by bringing two clamping blocks close together. The cable tray steel bars to be tested are easy to install and remove, and it can fix cable tray steel bars of different sizes. Furthermore, the position of the compression on the cable tray steel bars can be adjusted, making the testing more flexible and enabling the testing of the compressive strength of the cable tray steel bars at various locations.

[0004] However, in existing highway projects crossing canals and rivers, steel truss bridge decks are mostly made of precast concrete. But due to the large number of internal components and the limitations of steel trusses crossing canals and rivers, the installation of concrete bridge decks has certain limitations. In the past, bridge deck installation involved laying I-beams and steel plates on the steel truss to create a hoisting and transport channel. Small cranes were then used to hoist the decks to the installation location. The installation was done in a retraction sequence, with the transport channel being removed as the deck was hoisted. This traditional hoisting method used a large amount of I-beams, posed a high safety risk to the small cranes moving inside the steel truss, and resulted in inflexible crane boom steering and low installation accuracy. Summary of the Invention

[0005] The purpose of this invention is to provide a three-truss steel truss beam built-in gantry crane bridge panel installation device and construction method to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including a steel truss girder body, a track mounting assembly disposed on the surface of the steel truss girder body, a hanging door assembly disposed on the surface of the steel truss girder body, and a mobile power supply assembly disposed on the surface of the steel truss girder body; The steel truss body has three sets of diagonal steel frames connected to its surface. Each diagonal steel frame has multiple arrayed supporting steel frames connected to one end. The tops of the diagonal steel frames and supporting steel frames are fixedly connected to fixed beams. The diagonal steel frames, supporting steel frames and fixed beams form a three-truss steel truss. The track installation assembly includes two gantry crane tracks disposed on the surface of the steel truss body and one side of the inclined steel frame. The gantry crane tracks are parallel to each other and are slidably connected inside the track groove. The track groove is opened inside the support plate. The gantry crane moves as a whole by moving the support plate inside the three-truss steel truss. The gantry assembly includes a fixed rod fixedly connected to the surface of the support plate. One end of the fixed rod is fixedly connected to a truss. A moving groove is provided inside the truss. A crane is movably connected inside the moving groove. One end of the crane is connected to a traction mechanism. A lifting line is connected to the bottom of the crane. One end of the lifting line is connected to a precast slab. The precast slab is moved and lifted inside the three-truss steel beam assembly by the crane.

[0007] Preferably, the track mounting assembly further includes a base plate that is fitted and connected to the surface of the steel truss body, and a support leg is fixedly connected to the surface of the base plate, with a detachable trestle connected to one end of the support leg.

[0008] Preferably, the surface of the trestle is fitted with a gantry crane track, the surface of the base plate is fitted with a shock-absorbing spring, one end of the shock-absorbing spring is fitted with the bottom of the trestle, the support leg is disposed inside the shock-absorbing spring, and the surface of the base plate is provided with multiple screw holes.

[0009] Preferably, the hanging door assembly further includes hooks that are connected to the four corners of the precast slab surface, and the hanging line is connected to the inside of the hooks.

[0010] Preferably, the mobile power supply assembly includes multiple vertical rods detachably connected to the surface of the steel truss body. Each vertical rod has a fixing plate fixedly connected to both sides at one end. One side of each fixing plate extends to the outside of the vertical rod to form a cavity. An adjustment shaft is fitted inside the fixing plate.

[0011] Preferably, a support rod is fitted to the surface of the adjusting shaft, and a sliding contact line is fitted between the vertical rods to supply power to the traction mechanism and the crane during movement.

[0012] Preferably, the surface of the steel truss beam body is provided with a placement groove, and there are multiple placement grooves, with precast slabs connected inside the placement grooves.

[0013] Preferably, each of the three fixed beams has two protective bars detachably connected to its top. The fixed beams are connected to each other by a first crossbeam, which is horizontally placed. The first crossbeams are also connected to each other by a second crossbeam, which is triangularly distributed.

[0014] Preferably, the inclined steel frame has multiple stepped openings on its surface, and multiple protective rings are connected to the inclined steel frame surface, with the protective rings located at one end of the stepped opening.

[0015] A construction method for a three-truss steel girder with built-in gantry crane bridge deck installation device includes the following steps: Step A: First, install the gantry crane rails on the innermost and outermost longitudinal beams of a single inclined steel frame. Because there are shear studs on the longitudinal beams of the steel truss girder and connecting reinforcement bars on the bridge deck at the longitudinal beams of the steel truss girder, the gantry crane rails cannot be directly welded to the longitudinal beams. Using stirrups as the foundation for the rails, the installation positions and layout of the gantry crane rails are provided. The specific steps are as follows: Step (A1): The trestle foundation is made of welded steel bars and steel plates. The legs are composed of multiple ribbed steel bars, which extend above the shear studs on the longitudinal beams of the steel truss body. The bottom of the steel bars is set on the side longitudinal beams of the steel truss body. The steel bars are spaced at the same distance in both the longitudinal and transverse directions. A steel plate is welded to the top of the legs to form an integral trestle structure. Step (A2): Before the rail is installed, the surveyors lay out the position of the rail and then set up the rail supports according to the layout points. When processing the supports, it is necessary to ensure that the length of the support leg steel bars is consistent. Before welding, the supports are placed flat on the ground and a spirit level is used to check whether the steel plate of the supports is on the horizontal plane. If the steel plate is not found to be horizontal, it is adjusted first. Before the supports are installed, the technicians use a level to check the elevation of the top surface of each support. After the check, the supports are welded. Step (A3): When laying the gantry crane rails, ensure that the two ends of adjacent gantry crane rails are straight. Use a measuring ruler to check that the relative elevation difference between the two gantry crane rails on the same cross-section is between 1mm and 2mm, and the gap between the two rail joints on the same cross-section is between 1mm and 2mm. Install terminal limit devices and brake baffles 2m from both ends of the gantry crane rails to prevent crane derailment accidents. Set up trestles every 1.5m at the bottom of the rails. Use rail pressure plates to fix the rails on the trestles. The rails and the top surfaces of the trestles are welded together through the rail pressure plates. During installation, the rail joints on both sides are staggered, and the staggered distance is not equal to the wheel track. Use a ruler and feeler gauge to check that the offset of the joints on the left, right, and top sides is less than 1mm. Lay the rails on top of the trestles to form the gantry crane rail as a whole. The rails are made of ribbed steel bars welded together with steel plates. Set up trestles at equal intervals. Step B involves connecting the gantry crane track to the track groove at the bottom of the support plate, allowing the support plate to move on the gantry crane track. The fixed rods fixedly connected to the surface of the support plate move its truss, thereby moving its traction mechanism and the crane. The crane is connected to the hook detachably connected to the surface of the precast slab via a lifting line to lift the precast slab. Step C: The gantry crane uses a suspended sliding contact line for power supply. A vertical rod is installed on each of the crossbeams at both ends of the steel truss body. The sliding contact line is 2.5m above the ground. The sliding contact line is selected in an area close to the gantry crane track, and the installation position and the moving power supply facilities are set on the same side. The phase distance between the sliding contact lines is equal during installation. The connected and fixed sliding contact lines must not move or shake. All fasteners are checked to ensure they are tight after installation. At the same time, the parallelism of the sliding contact line is adjusted to make it parallel to the crane track to ensure the smooth operation of the current collector. The current collector traction arm is fixed to the fixed rod, and the current collector is installed at the lower plane of the traction arm and the sliding contact line. Step D: The precast slab is transported to the bridge site. The gantry crane is moved to the feeding side. The track installation assembly and the gantry assembly are combined to form a small gantry crane. An external crane is used to lift the bridge deck to a position above the steel truss body of the gantry crane. The slab is fed to the small gantry crane, which then moves along the track to lift the precast slab to the longitudinal bridge installation position. The small gantry crane is then adjusted to move the precast slab transversely to the placement slot position. The precast slab is then lowered to the top surface of the steel beam and slowly moved to align the longitudinal and transverse positions. The height is reduced, and the traction rope is manually pulled for precise alignment and installation in the placement slot. Step E: When the reinforcing bars of the precast slab collide, the principle is to move the secondary reinforcing bars to ensure the position of the main reinforcing bars. Since there are many protruding reinforcing bars on the precast slab and shear studs on the steel plate beam, pay attention to their positional relationship during installation to prevent them from conflicting with each other. If the protruding reinforcing bars conflict with the shear studs, adjust the reinforcing bars to ensure the positioning accuracy of the bridge deck. When hoisting the precast bridge deck, lift and lower it gently to prevent the shear keys on the edge of the precast slab from being hit. After the precast slab is in place, spot weld it to the connecting reinforcing bars of the middle plate and weld it in time. Welding is done on one side. Before welding, remove rust, oil, burrs, moisture and other substances that are not conducive to welding from the welding area. Remove the weld slag in time after welding. Step F: During the installation of the support trestles, shock-absorbing springs are fitted onto the surface of the support legs. That is, the base plate fixedly connected to the bottom of the support legs contacts the steel truss beam body, and is connected to the external bolts through multiple screw holes on the surface of the base plate. The support trestles are then welded and bolted together as a whole.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. By installing steel bars and steel plates as supports on the two outermost longitudinal beams of the steel truss girder, welding the gantry crane track foundation onto the supports, and installing a 5T small gantry crane on the track foundation, the precast steel truss slabs are transported to the bridge site. A 25T crane lifts the precast slabs and feeds them to the installed small gantry crane. The gantry crane then uses a lifting line to lift the precast slabs and move them along the gantry crane track. With the help of manual labor, the precast slabs are moved to the designed installation position, i.e., the placement slot is precisely aligned. Throughout the construction process, the gantry crane operates smoothly and flexibly, solving the problems of crane overturning and low installation accuracy that are common in traditional paving methods. This not only effectively improves construction efficiency but also ensures safety and quality, guaranteeing smooth construction.

[0017] 2. The bridge deck structure is formed by the steel truss girder body, inclined steel frame, supporting steel frame, and fixed beam. A groove is opened at the bottom of the steel truss girder body for installing precast slabs. Protective rods fixed to the top of the fixed beams provide safety protection for personnel working above. Step openings and protective rings on the inclined steel frame reduce the risk of falls for construction workers climbing. The first and second crossbeams and inclined rods increase the connection and stability of the steel truss girder body, inclined steel frame, supporting steel frame, and fixed beam. Legs and trestles are used to install the gantry crane rails. Shock-absorbing springs reduce the stress on the legs. The legs are connected to the steel truss girder body via a fixed bottom plate and bolt holes on its surface. The support plate is connected to the gantry crane rails via rail grooves. The support plate is fixed to the truss by fixing rods, and the crane and traction mechanism are placed and installed through the moving slots opened inside the truss, thus forming a small gantry crane structure. When lifting the precast slab, the lifting line can be connected to the hook that can be detachably connected to the surface of the precast slab, so that the crane pulls the lifting line to lift and move the precast slab. Vertical rods are detachably connected to both sides inside the steel truss body. The vertical rods are connected to the support rods by fixing plates, and the support rods are fixed by adjusting shafts. The fixing angle of the vertical rods can be adjusted by adjusting shafts, so the straightness of the sliding contact line can be controlled. The power supply to the crane and traction machine of the small gantry crane is transmitted through the sliding contact line. Thus, the small gantry crane is integrated into the steel truss body, which increases the convenience of precast slab installation. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a three-truss steel truss beam built-in gantry crane bridge panel installation device and construction method of the present invention. Figure 2 This is a schematic diagram of the second crossbeam structure of a three-truss steel truss beam built-in gantry crane bridge panel installation device and construction method of the present invention. Figure 3 This is a schematic diagram of the gantry crane slide rail structure of a three-truss steel girder built-in gantry crane bridge panel installation device and construction method of the present invention; Figure 4 This is a schematic diagram of the overall structure of a gantry crane according to the present invention, which is a three-truss steel truss beam built-in gantry crane bridge panel installation device and construction method. Figure 5 This is a schematic diagram of the bottom structure of the bridge traction mechanism of a bridge deck installation device and construction method for a three-truss steel girder built-in gantry crane bridge panel of the present invention. Figure 6 This is a schematic diagram of the support structure of a three-truss steel girder built-in gantry crane bridge panel installation device and construction method of the present invention. Figure 7 This is a schematic diagram of the sliding contact line structure of a three-truss steel girder built-in gantry crane bridge panel installation device and construction method of the present invention. Figure 8 This is a schematic diagram of the installation structure of a three-truss steel truss built-in gantry crane bridge panel installation device and construction method according to the present invention. Figure 9 This is a schematic diagram of the precast slab structure of a three-truss steel girder built-in gantry crane bridge panel installation device and construction method according to the present invention.

[0019] In the diagram: 1. Steel truss body; 2. Placement slot; 3. Inclined steel frame; 4. Supporting steel frame; 5. Fixed beam; 6. Guard rod; 7. First crossbeam; 8. Inclined rod; 9. Step opening; 10. Protective ring; 11. Precast slab; 1201. Support leg; 1202. Relay; 1203. Gantry crane track; 1204. Track slot; 1205. Support plate; 1206. Shock-absorbing spring; 1207. Base plate; 1208. Screw hole; 1301. Fixed rod; 1302. Truss; 1303. Moving slot; 1304. Crane; 1305. Traction mechanism; 1306. Lifting line; 1307. Hook; 14. Second crossbeam; 1501. Vertical rod; 1502. Fixed plate; 1503. Adjusting shaft; 1504. Support rod; 1505. Sliding contact line. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0021] Please see Figure 1-9As shown, a schematic diagram of the overall structure of a three-truss steel girder built-in gantry crane bridge panel installation device and construction method includes a steel truss girder body 1, a track installation assembly disposed on the surface of the steel truss girder body 1, a gantry crane assembly disposed on the surface of the steel truss girder body 1, and a mobile power supply assembly disposed on the surface of the steel truss girder body 1. Three sets of inclined steel frames 3 are connected to the surface of the steel truss girder body 1. Multiple arrayed support steel frames 4 are connected to one end of the inclined steel frames 3. Fixed beams 5 are fixedly connected to the top of the inclined steel frames 3 and the support steel frames 4. The three-truss steel girder is formed by the inclined steel frames 3, the support steel frames 4, and the fixed beams 5. The track installation assembly includes two gantry crane tracks 1203 disposed on the surface of the steel truss girder body 1 and one side of the inclined steel frames 3. The gantry crane tracks 1203 are parallel to each other. 203 is slidably connected inside the track groove 1204, which is opened inside the support plate 1205. The gantry crane moves as a whole by moving the support plate 1205 inside the three-truss steel beam. The gantry crane assembly includes a fixed rod 1301 fixedly connected to the surface of the support plate 1205. One end of the fixed rod 1301 is fixedly connected to a truss 1302. A moving groove 1303 is provided inside the truss 1302. A crane 1304 is movably connected inside the moving groove 1303. A traction mechanism 1305 is connected to one end of the crane 1304. A lifting line 1306 is connected to the bottom of the crane 1304. A precast slab 11 is connected to one end of the lifting line 1306. The precast slab 11 is moved and lifted by the crane 1304 inside the three-truss steel beam.

[0022] Specifically, the track installation assembly also includes a base plate 1207 that is connected to the surface of the steel truss body 1. A support leg 1201 is fixedly connected to the surface of the base plate 1207, and a detachable stool 1202 is connected to one end of the support leg 1201.

[0023] Specifically, the surface of the trestle 1202 is fitted with a gantry crane track 1203, the surface of the base plate 1207 is fitted with a shock-absorbing spring 1206, one end of the shock-absorbing spring 1206 is fitted with the bottom of the trestle 1202, the support leg 1201 is set inside the shock-absorbing spring 1206, and the surface of the base plate 1207 is provided with screw holes 1208, and there are multiple screw holes 1208.

[0024] Specifically, the hanging door assembly also includes hooks that are connected to the four corners of the surface of the precast slab 11, and the hanging line 1306 is connected inside the hooks, so that the precast slab 11 can be easily moved and adjusted through the hooks.

[0025] Specifically, the mobile power supply assembly includes multiple vertical rods 1501 detachably connected to the surface of the steel truss body 1. Fixing plates 1502 are fixedly connected to both sides of one end of each vertical rod 1501. One side of each fixing plate 1502 extends outside the vertical rod 1501, forming a cavity. An adjusting shaft 1503 is fitted inside the fixing plate 1502. The angle of the support rod 1504 is adjusted via the adjusting shaft 1503, facilitating the fixing of the vertical rod 1501 and thus allowing for the adjustment and straightening of the sliding contact line 1505. Specifically, a support rod 1504 is connected to the surface of the adjusting shaft 1503, and a sliding contact line 1505 is connected between the vertical rods 1501. The sliding contact line 1505 supplies power to the traction mechanism 1305 and the crane 1304 when they move.

[0026] Specifically, the surface of the steel truss beam body 1 is provided with a placement groove 2, and there are multiple placement grooves 2. The placement grooves 2 are connected to precast slabs 11.

[0027] Specifically, each of the three fixed beams 5 has two protective rods 6 detachably connected to its top. The fixed beams 5 are connected to each other by a first crossbeam 7, which is horizontally placed. The first crossbeams 7 are connected to each other by a second crossbeam 1307. The second crossbeams 1307 are multiple and distributed in a triangular shape.

[0028] Specifically, the inclined steel frame 3 has multiple stepped openings 9 on its surface, and multiple protective rings 10 are connected to the surface of the inclined steel frame 3. The protective rings 10 are located at one end of the stepped openings 9.

[0029] A construction method for a three-truss steel girder bridge deck panel installation device includes the following steps: Step A: First, install the gantry crane rails 1203 on the innermost and outermost longitudinal beams of a single inclined steel frame 3. Because there are shear studs on the longitudinal beams of the steel truss body 1, and the bridge deck panel has connecting steel bars at the longitudinal beams of the steel truss body 1, the gantry crane rails 1203 cannot be directly welded to the longitudinal beams. Using trestles 1202 as the foundation for the rails, the installation position and layout of the gantry crane rails 1203 are provided. The specific steps are as follows: Step (A1): The foundation of the trestle 1202 is made of steel bars and steel plates welded together. The support leg 1201 is composed of multiple ribbed steel bars, which are higher than the shear studs on the longitudinal beam of the steel truss body 1. The bottom of the steel bars is set on the side longitudinal beam of the steel truss body 1. The steel bars are spaced at the same distance in the longitudinal and transverse directions. A steel plate is welded to the top of the support leg 1201 to form an integral trestle 1202 structure. Step (A2): Before the rail is installed, the surveyors lay out the position of the rail and then lay out the rail supports 1202 according to the layout points. When processing the supports 1202, it is necessary to ensure that the length of the support leg 1201 steel bars is consistent. Before welding, the supports 1202 are placed flat on the ground and a spirit level is used to check whether the steel plate of the supports 1202 is on the horizontal plane. If the steel plate is found to be not horizontal, it is adjusted first. Before the supports 1202 are installed, the technicians use a level to check the elevation of the top surface of each supports 1202. After the check, the supports 1202 are welded. Step (A3): When laying the gantry crane rails 1203, ensure that the two end faces of adjacent gantry crane rails 1203 are straight. Use a measuring ruler to check that the relative elevation difference between the two gantry crane rails 1203 on the same cross-section is between 1mm and 2mm, and the gap between the joints of the two rails on the same cross-section is between 1mm and 2mm. Install end limit devices and brake baffles 2m from both ends of the gantry crane rails 1203 to prevent crane derailment accidents. Install 12 trestles 12 every 1.5m at the bottom of the rails. 02. The rails are fixed on the trestles 1202 using rail pressure plates. The rails and the top surface of the trestles 1202 are welded together using the rail pressure plates. During installation, the rail joints on both sides are staggered, and the staggered distance is not equal to the wheel track. A ruler and feeler gauge are used to check that the offset of the joints on the left, right, and top sides is less than 1mm. The rails are laid on top of the trestles (1202) to form the gantry crane rail 1203 as a whole. The rails are made of ribbed steel bars welded together with steel plates. The trestles 1202 are set at equal intervals. Step B involves connecting the gantry crane track 1203 to the track groove 1204 at the bottom of the support plate 1205, allowing the support plate 1205 to move on the gantry crane track 1203. The fixed rod 1301 fixedly connected to the surface of the support plate 1205 drives its truss 1302 to move, thereby driving its traction mechanism 1305 and crane 1304 to move. The crane 1304 is connected to the hook detachably connected to the surface of the precast slab 11 through the lifting line 1306 to lift the precast slab 11. Step C: The gantry crane is powered by a suspended sliding contact line 1505. A vertical rod 1501 is installed on each of the crossbeams at both ends of the steel truss body 1. The sliding contact line 1505 is 2.5m above the ground. The sliding contact line 1505 is selected in an area close to the gantry crane track 1203, and the installation position and the moving power supply facility are set on the same side. The spacing between the sliding contact lines 1505 is equal during installation. The connected and fixed sliding contact lines 1505 must not move or shake. All fasteners are checked for tightness after installation. At the same time, the parallelism of the sliding contact line 1505 is adjusted to make it parallel to the traveling track to ensure the smooth operation of the current collector. The current collector traction arm is fixed on the fixed rod 1301. The current collector is installed at the lower plane of the traction arm and the sliding contact line. Step D: The precast slab 11 is transported to the bridge site. The gantry crane is moved to the feeding side. The track installation assembly and the gantry assembly are combined to form a small gantry crane. The external crane 1304 is used to lift the bridge deck to the position above the steel truss body 1 of the gantry crane. The slab is fed to the small gantry crane. Then, the small gantry crane travels on the track to lift the precast slab 11 to the longitudinal bridge installation position. The precast slab 11 is then moved transversely to the placement slot 2 by adjusting the small gantry crane. The precast slab 11 is then lowered to the top surface of the steel beam and slowly moved to the longitudinal and transverse positions for alignment. The height is reduced, and the traction rope is manually pulled for precise alignment and installation in the placement slot 2. Step E: When the reinforcing bars of the precast slab 11 collide, the principle is to move the secondary reinforcing bars to ensure the position of the main reinforcing bars. Since there are many shear studs on the precast slab 11 and the shear bars on the steel plate beam, pay attention to their positional relationship during installation to prevent them from conflicting with each other. If the shear studs collide with the shear bars, adjust the reinforcing bars to ensure the positioning accuracy of the bridge deck. When hoisting the precast bridge deck, lift and lower it gently to prevent the shear keys on the edge of the precast slab 11 from being hit. After the precast slab 11 is in place, spot weld it to the connecting reinforcing bars of the middle plate and weld it in time. Welding is done on one side. Before welding, remove rust, oil, burrs, moisture and other substances that are not conducive to welding from the welding area. Remove the weld slag in time after welding. Step F: When installing the support 1202, a shock-absorbing spring 1206 is fitted onto the surface of the support leg 1201. That is, the base plate 1207 fixedly connected to the bottom of the support leg 1201 contacts the steel truss body 1. The support 1202 is then connected to the external bolts through multiple screw holes 1208 on the surface of the base plate 1207. The support 1202 is then welded and bolted together as a whole.

[0030] By installing steel bars and steel plates to form supports 1202 on the two outermost longitudinal beams of the steel truss girder body 1, welding the foundation of the gantry crane track 1203 onto the supports 1202, and installing a 5T small gantry crane on the track foundation, after the precast steel truss girder slab 11 is transported to the bridge site, a 25T crane 1304 lifts the precast slab 11 and feeds it to the installed small gantry crane. The gantry crane then uses a lifting line 1306 to lift the precast slab 11 and move it along the gantry crane track 1203. With the help of manual labor, the precast slab 11 is moved to the designed installation position, i.e., the placement groove 2, for precise alignment. Throughout the construction process, the gantry crane operates smoothly and flexibly, solving the problem of the crane 1304 being prone to tipping during the traditional paving of passageways. The problem of insufficient installation precision has been addressed by improving the construction efficiency of the precast slab 11 installation, ensuring safety and quality, and guaranteeing smooth construction. The steel truss body 1, inclined steel frame 3, supporting steel frame 4, and fixed beam 5 form an integrated bridge deck structure. A groove 2 is provided at the bottom of the steel truss body 1 for installing the precast slab 11. A protective rod 6 fixedly connected to the top of the fixed beam 5 provides safety protection for personnel working above. Step openings 9 and protective rings 10 on the inclined steel frame 3 reduce the risk of falls for construction workers climbing. The first crossbeam 7, second crossbeam 1307, hooks 14, and inclined rods 8 enhance the connection and stability of the steel truss body 1, inclined steel frame 3, supporting steel frame 4, and fixed beam 5. The gantry crane track 1203 is installed via outriggers 1201 and trestles 1202. Shock-absorbing springs 1206 reduce the stress on the outriggers 1201. The outriggers 1201 are connected to the steel truss body 1 via a bottom plate 1207 and screw holes 1208. The support plate 1205 is connected to the gantry crane track 1203 via a track groove 1204. The support plate 1205 is then fixed to the truss 1302 via a fixing rod 1301. The crane 1304 and traction mechanism 1305 are placed and installed via a moving groove 1303 inside the truss 1302, thus forming a small gantry crane structure. When lifting the precast slab 11, the lifting line 1 can be... The hook 1306 is detachably connected to the surface of the precast slab 11, so that the crane 1304 pulls the lifting line 1306 to lift and move the precast slab 11. That is, vertical rods 1501 are detachably connected to both sides inside the steel truss body 1. The vertical rods 1501 are connected to the support rods 1504 through the fixing plate 1502. The support rods 1504 are fixed through the adjusting shaft 1503. The fixing angle of the vertical rods 1501 can be adjusted through the adjusting shaft 1503, so the straightness of the sliding contact line 1505 can be controlled. The crane 1304 and the traction machine of the small gantry crane are powered through the sliding contact line 1505. Thus, the small gantry crane is present in the steel truss body 1, which increases the convenience of installing the precast slab 11.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A three-truss steel truss beam built-in gantry crane bridge panel installation device, characterized in that: It includes a steel truss body (1), a track mounting assembly disposed on the surface of the steel truss body (1), a door assembly disposed on the surface of the steel truss body (1), and a mobile power supply assembly disposed on the surface of the steel truss body (1). The steel truss body (1) has three sets of inclined steel frames (3) connected to its surface. One end of the inclined steel frame (3) is connected to a plurality of supporting steel frames (4) arranged in an array. The top of the inclined steel frame (3) and the supporting steel frame (4) is fixedly connected to a fixed beam (5). The inclined steel frame (3), the supporting steel frame (4) and the fixed beam (5) form a three-truss steel truss. The track installation assembly includes a gantry crane track (1203) disposed on the surface of the steel truss body (1) and on one side of the inclined steel frame (3). There are two gantry crane tracks (1203) distributed in parallel. The gantry crane tracks (1203) are slidably connected inside the track groove (1204). The track groove (1204) is opened inside the support plate (1205). The gantry crane moves as a whole by moving the support plate (1205) inside the three-truss steel truss. The gantry assembly includes a fixed rod (1301) fixedly connected to the surface of the support plate (1205). One end of the fixed rod (1301) is fixedly connected to a truss (1302). The truss (1302) has a moving groove (1303) inside. A crane (1304) is movably connected inside the moving groove (1303). One end of the crane (1304) is connected to a traction mechanism (1305). The bottom of the crane (1304) is connected to a lifting line (1306). One end of the lifting line (1306) is connected to a precast slab (11). The precast slab (11) is moved and lifted inside the three-truss steel beam assembly by the crane (1304).

2. The three-truss steel truss bridge built-in gantry bridge deck panel installation device according to claim 1, characterized in that: The track installation assembly also includes a base plate (1207) that is fitted and connected to the surface of the steel truss body (1). A support leg (1201) is fixedly connected to the surface of the base plate (1207), and a trestle (1202) is detachably connected to one end of the support leg (1201).

3. The three-truss steel truss girder built-in gantry bridge deck panel installation device according to claim 2, characterized in that: The trestle (1202) is fitted with a gantry crane track (1203), and the base plate (1207) is fitted with a shock-absorbing spring (1206). One end of the shock-absorbing spring (1206) is fitted to the bottom of the trestle (1202), and the support leg (1201) is located inside the shock-absorbing spring (1206). The base plate (1207) has multiple screw holes (1208) on its surface.

4. The three-truss steel truss girder built-in gantry bridge deck panel installation device according to claim 1, characterized in that: The hanging door assembly also includes hooks that are connected to the four corners of the surface of the precast slab (11), and the hanging line (1306) is connected to the inside of the hooks.

5. The three-truss steel truss girder built-in gantry bridge deck panel installation device according to claim 1, characterized in that: The mobile power supply assembly includes multiple vertical rods (1501) detachably connected to the surface of the steel truss body (1). One end of each vertical rod (1501) is fixedly connected to two sides of a fixing plate (1502). One side of each fixing plate (1502) extends to the outside of the vertical rod (1501) to form a cavity. An adjusting shaft (1503) is fitted inside the fixing plate (1502).

6. A three-truss steel truss girder built-in gantry bridge deck panel installation device according to claim 5, characterized in that: The adjustment shaft (1503) is fitted with a support rod (1504), and the vertical rods (1501) are fitted with a sliding contact line (1505). The sliding contact line (1505) supplies power to the traction mechanism (1305) and the crane (1304) when they move.

7. The three-truss steel truss girder built-in gantry bridge deck panel installation device according to claim 1, characterized in that: The steel truss body (1) has a placement groove (2) on its surface. There are multiple placement grooves (2), and a precast slab (11) is connected inside the placement groove (2).

8. A three-legged steel truss girder built-in gantry bridge deck panel installation device according to claim 1, characterized in that: The top of each of the three fixed beams (5) is detachably connected to two protective rods (6). The fixed beams (5) are connected to each other by a first crossbeam (7). There are multiple first crossbeams (7) and they are placed horizontally. The first crossbeams (7) are connected to each other by a second crossbeam (1307). There are multiple second crossbeams (1307) and they are distributed in a triangular shape.

9. The installation device for a three-truss steel truss beam with an internal gantry crane panel as described in claim 1, characterized in that: The inclined steel frame (3) has multiple stepped openings (9) on its surface, and multiple protective rings (10) are connected to the surface of the inclined steel frame (3). The protective rings (10) are located at one end of the stepped openings (9).

10. A construction method for a three-truss steel truss beam built-in gantry crane bridge panel installation device according to any one of claims 1-9, characterized in that: Includes the following steps: Step A: First, install the gantry crane rails (1203) on the innermost and outermost longitudinal beams of the single inclined steel frame (3). Because there are shear studs on the longitudinal beams of the steel truss body (1) and the bridge deck has connecting steel bars at the longitudinal beams of the steel truss body (1), the gantry crane rails (1203) cannot be directly welded to the longitudinal beams. Instead, use trestles (1202) as the foundation for the rails to provide the installation position and layout for the gantry crane rails (1203). The specific steps are as follows: Step (A1): The foundation of the trestle (1202) is made of steel bars and steel plates welded together. The support leg (1201) is composed of multiple ribbed steel bars, which are higher than the shear studs on the longitudinal beam of the steel truss body (1). The bottom of the steel bars is set on the side longitudinal beam of the steel truss body (1). The steel bars are spaced at the same distance in the longitudinal and transverse directions. A steel plate is welded on the top of the support leg (1201) to form an integral trestle (1202) structure. Step (A2): Before the rail is installed, the surveyors lay out the position of the rail and then set up the rail supports (1202) according to the layout points. When processing the supports (1202), it is necessary to ensure that the length of the reinforcing bars of the legs (1201) is consistent. Before welding, the supports (1202) are placed flat on the ground and a spirit level is used to check whether the steel plate of the supports (1202) is on the horizontal plane. If the steel plate is found to be not horizontal, it is adjusted first. Before the supports (1202) are installed, the technicians use a level to check the elevation of the top surface of each support (1202). After the check, the supports (1202) are welded. Step (A3): When laying the gantry crane rails (1203), ensure that the two ends of adjacent gantry crane rails (1203) are straight. Use a measuring ruler to check that the relative elevation difference between the two gantry crane rails (1203) on the same cross-section is between 1mm and 2mm, and the gap between the two rail joints on the same cross-section is between 1mm and 2mm. Install terminal limit devices and brake baffles 2m from both ends of the gantry crane rails (1203) to prevent crane derailment accidents. Install trestles (1203) every 1.5m at the bottom of the rails. 02), the rails are fixed on the trestles (1202) using rail pressure plates. The rails and the top surface of the trestles (1202) are welded together through the rail pressure plates. During installation, the rail joints on both sides are staggered, and the staggered distance is not equal to the wheel track. A ruler and feeler gauge are used to check that the offset of the joints on the left, right and top sides is less than 1mm. The rails are laid on the trestles (1202) to form the gantry crane rail (1203) as a whole. The rails are made of ribbed steel bars welded together with steel plates. One trestle (1202) is set at the same interval. Step B, that is, the gantry crane track (1203) is connected to the track groove (1204) opened at the bottom of the support plate (1205), so that the support plate (1205) can move on the gantry crane track (1203), and the fixed rod (1301) fixedly connected to the surface of the support plate (1205) drives its truss (1302) to move, thereby driving its traction mechanism (1305) and crane (1304) to move. The crane (1304) is connected to the hook detachably connected to the surface of the precast slab (11) through the lifting line (1306) to lift the precast slab (11); Step C: The gantry crane is powered by a suspended sliding contact line (1505). A vertical rod (1501) is installed on each of the two crossbeams at both ends of the steel truss body (1). The sliding contact line (1505) is 2.5m above the ground. The sliding contact line (1505) is selected in an area close to the gantry crane track (1203). The installation position and the moving power supply facility are set on the same side. The sliding contact lines (1505) are installed with equal spacing between each other. The fixed sliding contact lines (1505) must not move or shake. All fasteners are checked and tightened after installation. At the same time, the parallelism of the sliding contact line (1505) is adjusted to make it parallel to the crane track to ensure the smooth operation of the current collector. The current collector traction arm is fixed on the fixed rod (1301). The current collector is installed on the lower plane of the traction arm and the sliding contact line. Step D: The precast slab (11) is transported to the bridge site. The gantry crane is moved to the side of the beam feeding. The track installation component and the gantry component are combined to form a small gantry crane. An external crane (1304) is used to lift the bridge deck to the position above the steel truss beam body (1) of the gantry crane. The slab is fed to the small gantry crane. Then, the small gantry crane moves on the track to lift the precast slab (11) to the longitudinal bridge installation position. The precast slab (11) is then moved to the placement slot (2) by adjusting the small gantry crane. The precast slab (11) is then lowered to the top surface of the steel beam and slowly moved to the longitudinal and transverse positions for alignment. The height is reduced, and the traction rope is manually pulled for precise alignment. The slab is then installed in the placement slot (2). Step E: If the reinforcing bars of the precast slab (11) collide, the principle is to move the secondary reinforcing bars to ensure the position of the main reinforcing bars. Since there are many shear studs on the precast slab (11) and the steel plate beam, pay attention to the positional relationship between them during installation to prevent mutual conflict. If the shear studs collide with the shear studs, adjust the reinforcing bars to ensure the positioning accuracy of the bridge deck. When hoisting the precast bridge deck, lift and drop gently to prevent the shear keys on the edge of the precast slab (11) from being hit. After the precast slab (11) is in place, spot weld it to the connecting reinforcing bars of the middle plate and weld it in time. Welding is done on one side. Before welding, remove rust, oil, burrs, moisture and other substances that are not conducive to welding from the welding part. Remove the welding slag in time after welding. Step F: When installing the trestle (1202), a shock-absorbing spring (1206) is fitted onto the surface of the support leg (1201). That is, the bottom plate (1207) fixedly connected to the bottom of the support leg (1201) contacts the steel truss body (1). The trestle (1202) is connected to the external bolts through multiple screw holes (1208) on the surface of the bottom plate (1207). The trestle (1202) is welded and screwed together as a whole.

Images