Temporary support tooling for replacing the tensile and compressive bearings of bridges and its replacement construction method

Abstract

A temporary bearing tooling for replacing the tension and compression bearings of a bridge, comprising an upper backing plate assembly, an upper tooling assembly, a middle tooling assembly, and a lower tooling assembly; the upper backing plate assembly includes an upper backing plate anchor steel plate, an upper backing plate connecting steel plate, an L-shaped upper backing plate buckle plate, and an upper backing plate polytetrafluoroethylene plate arranged at the topmost; the upper tooling assembly includes an upper tooling polytetrafluoroethylene plate, an upper tooling upper steel plate located on the lower end face of the upper tooling polytetrafluoroethylene plate, an upper tooling lower backing plate, an upper tooling transverse stiffening plate, and an upper tooling longitudinal stiffening plate; the middle tooling assembly includes a middle tooling upper backing plate, a middle tooling longitudinal stiffening plate, a middle tooling transverse stiffening plate, and a middle tooling lower backing plate; the lower tooling assembly includes a lower tooling upper backing plate, a lower tooling transverse stiffening plate, a lower tooling longitudinal stiffening plate, and a lower tooling lower backing plate; it can replace the damaged tension and compression bearings in time without interrupting traffic on the bridge deck and without using the method of adding counterweights to the bridge deck, and it is convenient and fast to install and disassemble, with good economy.

Description

Technical Field

[0001] The invention relates to a temporary support tool for a bridge, in particular to a temporary support tool for replacing a tension and compression support of a bridge and a replacement construction method thereof. Background Art

[0002] As a cable-stayed system, cable-stayed bridges are the main type of long-span bridges because they have a larger span capacity than beam bridges. Generally speaking, cable-stayed bridges with a span of 300 to 1,400 meters are about 30% cheaper than suspension bridges. Therefore, cable-stayed bridges are deeply loved by bridge designers and builders all over the world.

[0003] Cable-stayed bridges can be divided into floating systems, semi-floating systems, tower-beam consolidation systems and rigid frame systems according to the combination of towers, beams and piers. No matter which system of cable-stayed bridges is adopted, the existence of bridge bearings is indispensable. Bridge bearings are important components connecting the superstructure and substructure of the bridge. They can reliably transmit the reaction force and deformation (displacement and rotation) of the superstructure of the bridge to the substructure of the bridge, so that the actual stress condition of the structure is consistent with the theoretical diagram of the calculation. Simply put, the bearing is a device erected on the top surface of the pier → platform to support the superstructure of the bridge. Its function is to fix the superstructure to the pier, bear the various forces acting on the superstructure, and reliably transmit it to the pier; under the action of load, temperature, concrete shrinkage and creep, the bearing can adapt to the rotation and displacement of the superstructure, so that the superstructure can deform freely without generating additional additional force.

[0004] During the construction of engineering projects, cable-stayed bridges are mainly composed of pylons, main beams, and cables. It is a structural system composed of pressure-bearing pylons, tension-bearing cables, and bending-bearing main beams. Its tension and compression bearings bear part of the main beam's dead load and vehicle live load. Under the operating conditions of the bridge, its internal structure must not only meet the requirements of the compressive stress of part of the main beam's dead load and vehicle live load, but also meet the requirements of the tensile force under the environment of the main beam's amplitude constantly changing. Although there are many types of tension and compression bearings for large cable-stayed bridges in the domestic and foreign markets, their material properties and product quality vary greatly. During the operation period of the bridge, the tension and compression bearings are squeezed and deformed due to long-term alternating loads, main beam rotation deviation, aging of material properties, and wear. At the same time, there is a lack of maintenance experience in the later maintenance, and it cannot be discovered and handled in time, resulting in damage to the tension and compression bearings.

[0005] At present, the replacement of the tensile and compressive bearings of bridges in the industry mainly adopts the method of ballast counterweight on the bridge deck. When using the ballast counterweight method on the bridge deck to replace the tensile and compressive bearings: First, the traffic on the bridge deck is interrupted, which will not only cause economic losses, but also have a greater negative social impact; Second, a large amount of manpower, material resources and financial resources are invested, increasing the maintenance cost; Third, adding ballast counterweights on the bridge deck takes a long time and has low work efficiency. The ballast counterweights change the redistribution of internal stresses in the bridge to a certain extent, and it is easy to cause uneven changes in local cables and main girders. Summary of the Invention

[0006] The problem to be solved by the present invention is that in the existing technology, the replacement of the tensile and compressive bearings of bridges in the industry mainly adopts the method of ballast counterweight on the bridge deck. This method has the following problems: First, the traffic on the bridge deck is interrupted, which will not only cause economic losses, but also have a greater negative social impact; Second, a large amount of manpower, material resources and financial resources are invested, increasing the maintenance cost; Third, adding ballast counterweights on the bridge deck takes a long time and has low work efficiency. The ballast counterweights change the redistribution of internal stresses in the bridge to a certain extent, and it is easy to cause uneven changes in local cables and main girders.

[0007] The technical solution adopted by the present invention is: A temporary bearing tooling for replacing the tensile and compressive bearings of bridges, characterized in that it includes an upper backing plate assembly, an upper tooling assembly, a middle tooling assembly, a lower tooling assembly and connecting bolts;

[0008] The upper backing plate assembly includes an upper backing plate anchor steel plate arranged at the topmost end, an upper backing plate connecting steel plate located on the lower end face of the upper backing plate anchor steel plate, L-shaped upper backing plate buckles, and upper backing plate polytetrafluoroethylene plates. There are two L-shaped upper backing plate buckles, which are symmetrically and fixedly arranged on both sides of the lower end face of the upper backing plate connecting steel plate. There are two upper backing plate polytetrafluoroethylene plates, which are symmetrically and fixedly arranged at the inner horizontal end faces of each L-shaped upper backing plate buckle;

[0009] The upper tooling assembly includes an upper tooling polytetrafluoroethylene plate, an upper tooling upper steel plate located on the lower end face of the upper tooling polytetrafluoroethylene plate, an upper tooling lower backing plate located below the upper tooling upper steel plate, an upper tooling transverse stiffening plate and an upper tooling longitudinal stiffening plate. The upper tooling transverse stiffening plate is fixedly arranged between the upper tooling upper steel plate and the upper tooling lower backing plate. There are two upper tooling longitudinal stiffening plates, which are symmetrically and fixedly arranged on both sides of the upper tooling transverse stiffening plate;

[0010] The middle tooling assembly includes a middle tooling upper backing plate, middle tooling longitudinal stiffening plates, middle tooling transverse stiffening plates and middle tooling lower backing plates. The middle tooling transverse stiffening plates are fixedly arranged between the middle tooling upper backing plate and the middle tooling lower backing plates. There are two middle tooling longitudinal stiffening plates, which are symmetrically and fixedly arranged on both sides of the middle tooling transverse stiffening plates;

[0011] The lower tooling assembly includes a lower tooling upper backing plate, a lower tooling transverse stiffening plate, a lower tooling longitudinal stiffening plate, and a lower tooling lower backing plate. The lower tooling transverse stiffening plate is fixedly arranged between the lower tooling upper backing plate and the lower tooling lower backing plate. There are two lower tooling longitudinal stiffening plates, which are symmetrically and fixedly arranged on both sides of the lower tooling transverse stiffening plate.

[0012] The upper tooling polytetrafluoroethylene plate and the upper tooling upper steel plate are integrally embedded in the stepped grooves formed by the L-shaped upper backing plate fasteners on the left and right sides. The lower tooling lower backing plate is fixedly connected to the middle tooling upper backing plate. The middle tooling lower backing plate is fixedly connected to the lower tooling upper backing plate'.

[0013] The upper backing plate anchor steel plate and the upper backing plate connecting steel plate are integrally anchored to the beam bottom by means of planted connecting bolts and the nuts on the connecting bolts are tightened. The lower tooling lower backing plate is anchored to the top surface of the capping beam or the connecting beam by means of planted connecting bolts.

[0014] Further, there is a lower tooling upper diagonal stiffening plate on each side between the upper ends of the two lower tooling longitudinal stiffening plates and the lower end surface of the lower tooling upper backing plate. There is a lower tooling lower diagonal stiffening plate on each side between the lower ends of the two lower tooling longitudinal stiffening plates and the upper end surface of the lower tooling lower backing plate.

[0015] Further, the surfaces of the upper tooling polytetrafluoroethylene plate and the upper backing plate polytetrafluoroethylene plate are both coated with lubricating oil.

[0016] Further, the lubricating oil is silicone grease.

[0017] Further, the lower tooling lower backing plate and the middle tooling upper backing plate are fixedly connected by connecting bolts.

[0018] Further, the middle tooling lower backing plate and the lower tooling upper backing plate are fixedly connected by connecting bolts.

[0019] Further, the upper backing plate connecting steel plate and the upper tooling fastener are connected by groove welding.

[0020] Further, the number of the upper tooling assemblies and the middle tooling assemblies is not less than one.

[0021] The beneficial effects and characteristics of the present invention are as follows: This construction method mainly transfers the upper structure (box girder) of the bridge to the temporary supports through system conversion, uses the temporary supports to replace the permanent supports, and then conducts the second system conversion after the support replacement is completed to transfer the entire upper structure of the bridge to the newly installed permanent supports. The advantages of the temporary supports are: compressive resistance, anti-pulling, easy sliding, and having the function of lateral restraint, and can meet the use functions of the permanent supports to a certain extent.

[0022] This method ingeniously uses temporary bearings to replace permanent bearings for secondary system conversion, successfully achieving the replacement of the tension and compression bearings of a cable-stayed bridge without interrupting traffic. It not only effectively avoids the risk of traffic interruption during construction, but also reduces maintenance costs and social impacts better.

[0023] First: Without interrupting traffic on the bridge deck, the damaged tension and compression bearings can be replaced in a timely manner, reducing economic losses and significantly minimizing the negative social impacts.

[0024] Second: Install temporary bearing tooling near the original bearings and conduct synchronous conversion under the original structural system, greatly saving maintenance costs.

[0025] Third: There is no need to adopt the method of bridge deck counterweight. The temporary bearing tooling can not only meet the tensile stress requirements of the bridge, but also meet the compressive stress requirements of the bridge, greatly reducing maintenance costs, improving work efficiency, and more flexibly and conveniently completing the synchronous conversion under the original structural system.

[0026] Fourth: The temporary bearing tooling adopts a segmented design, and each tooling is connected and fastened with bolts. This can not only ensure convenient and quick installation and disassembly between the toolings, but also meet the space requirements for on-site installation, and better serve the on-site construction.

[0027] Fifth: Due to the setting of polytetrafluoroethylene plates, when the temporary bearing tooling is in tension or compression, it can well cause the original structure to have lateral or longitudinal slippage; relying on the characteristics of small friction and convenient slippage of the polyethylene tetrafluoride plates, it can meet the purpose of system conversion of the concrete structure cable-stayed bridge during the replacement of tension and compression bearings. Description of the Drawings

[0028] Figure 1 : Schematic diagram of the overall structure of the preferred embodiment of the present invention (the shapes of the components in the figure are only for illustration, and there can actually be various shapes);

[0029] Figure 2 : Side view of the preferred embodiment of the present invention;

[0030] Figure 3 : Structural diagram of the upper bearing plate of the preferred embodiment of the present invention;

[0031] Figure 4 : Structural diagram of the upper tooling of the preferred embodiment of the present invention;

[0032] Figure 5 : Structural diagram of the middle tooling of the preferred embodiment of the present invention;

[0033] Figure 6 : Structural diagram of the lower tooling of the preferred embodiment of the present invention;

[0034] Figure 7:Structural diagram of the connecting bolt in the preferred embodiment of the present invention;

[0035] Among them, 0 - upper backing plate anchoring steel plate, 1 - upper backing plate connecting steel plate, 2 - upper tooling polytetrafluoroethylene plate, 3 - upper tooling upper steel plate, 4 - upper backing plate buckle, 5 - upper backing plate polytetrafluoroethylene plate, 6 - upper tooling longitudinal stiffening plate, 7 - upper tooling lower backing plate, 7' - middle tooling upper backing plate, 8 - upper tooling transverse stiffening plate, 9 - middle tooling longitudinal stiffening plate, 10 - middle tooling transverse stiffening plate, 11 - middle tooling lower backing plate, 11' - lower tooling upper backing plate, 12 - lower tooling upper diagonal stiffening plate, 13 - lower tooling longitudinal stiffening plate, 14 - lower tooling lower diagonal stiffening plate, 15 - lower tooling lower backing plate, 16 - connecting bolt, 17 - lower tooling transverse stiffening plate. Detailed implementation manners

[0036] The present invention will be further described below with reference to the accompanying drawings:

[0037] A temporary support tooling for replacing the tension and compression bearings of a bridge, comprising an upper backing plate assembly, an upper tooling assembly, a middle tooling assembly, a lower tooling assembly and a connecting bolt;

[0038] The upper backing plate assembly includes an upper backing plate anchoring steel plate 0 arranged at the topmost end, an upper backing plate connecting steel plate 1 located on the lower end face of the upper backing plate anchoring steel plate, an L-shaped upper backing plate buckle 4 and an upper backing plate polytetrafluoroethylene plate 5. There are two L-shaped upper backing plate buckles 4, which are symmetrically and fixedly arranged on both sides of the lower end face of the upper backing plate connecting steel plate 1. There are two upper backing plate polytetrafluoroethylene plates 5, which can also be made of other materials, such as plates with low friction coefficients like plexiglass, alloy, graphite, etc., and are symmetrically and fixedly arranged at the inner horizontal end faces of each L-shaped upper backing plate buckle 4;

[0039] The upper tooling assembly includes an upper tooling polytetrafluoroethylene plate 2, an upper tooling upper steel plate 3 located on the lower end face of the upper tooling polytetrafluoroethylene plate, an upper tooling lower backing plate 7 located below the upper tooling upper steel plate, an upper tooling transverse stiffening plate 8 and an upper tooling longitudinal stiffening plate 6. The upper tooling transverse stiffening plate 8 is fixedly arranged between the upper tooling upper steel plate and the upper tooling lower backing plate. There are two upper tooling longitudinal stiffening plates 6, which are symmetrically and fixedly arranged on both sides of the upper tooling transverse stiffening plate 8;

[0040] The middle tooling assembly includes a middle tooling upper backing plate 7', a middle tooling longitudinal stiffening plate 9, a middle tooling transverse stiffening plate 10 and a middle tooling lower backing plate 11. The middle tooling transverse stiffening plate 10 is fixedly arranged between the middle tooling upper backing plate 7' and the middle tooling lower backing plate 11. There are two middle tooling longitudinal stiffening plates 9, which are symmetrically and fixedly arranged on both sides of the middle tooling transverse stiffening plate 10;

[0041] The lower tooling assembly includes a lower tooling upper backing plate 11', a lower tooling transverse stiffening plate 17, a lower tooling longitudinal stiffening plate 13 and a lower tooling lower backing plate 15. The lower tooling transverse stiffening plate 17 is fixedly arranged between the lower tooling upper backing plate 11' and the lower tooling lower backing plate 15. There are two lower tooling longitudinal stiffening plates 13, which are symmetrically and fixedly arranged on both sides of the lower tooling transverse stiffening plate 17;

[0042] The upper tooling polytetrafluoroethylene plate 2 and the upper tooling upper steel plate 3 are integrally embedded in the stepped grooves formed by the L-shaped upper backing plate fasteners 4 on the left and right sides; The lower tooling lower backing plate 7 and the middle tooling upper backing plate 7' are fixedly connected; The middle tooling lower backing plate 11 and the lower tooling upper backing plate 11' are fixedly connected;

[0043] The upper backing plate anchor steel plate 0 and the upper backing plate connecting steel plate 1 are integrally anchored to the beam bottom by means of planted connecting bolts (and tighten the nuts on the connecting bolts); The lower tooling lower backing plate 15 is anchored to the top surface of the capping beam or connecting beam by means of planted connecting bolts (and tighten the nuts on the connecting bolts)

[0044] When the temporary support tooling is subjected to an upward pulling force, the connecting bolts planted on the lower tooling must meet the pull-out requirements. When the temporary support tooling is subjected to a downward pressure, the stiffening plates in the tooling must meet the compressive stress requirements.

[0045] There are various fixed connection methods mentioned above, which can be connection methods such as welding, riveting, bonding, snap connection, hinge connection and pin connection.

[0046] On both sides of the upper ends of the lower tooling longitudinal stiffening plates 13, there is a lower tooling upper diagonal stiffening plate 12 between each side and the lower end surface of the lower tooling upper backing plate 11'; On both sides of the lower ends of the lower tooling longitudinal stiffening plates 13, there is a lower tooling lower diagonal stiffening plate 14 between each side and the upper end surface of the lower tooling lower backing plate 15.

[0047] The surfaces of the upper tooling polytetrafluoroethylene plate 2 and the upper backing plate polytetrafluoroethylene plate 5 are both coated with lubricating oil, such as silicone grease oil and other lubricating oils.

[0048] The lower tooling lower backing plate 7 and the middle tooling upper backing plate 7' are fixedly connected by connecting bolts.

[0049] The middle tooling lower backing plate 11 and the lower tooling upper backing plate 11' are fixedly connected by connecting bolts.

[0050] The upper backing plate connecting steel plate 1 and the upper backing plate fastener 4 are connected by groove welding.

[0051] During the actual construction process, according to the actual required height situation, the number of the upper tooling assembly and the middle tooling assembly can be no less than one.

[0052] Construction method

[0053] The replacement construction method of the above-mentioned temporary bearing tooling for bridge tension and compression bearings is characterized by the following steps:

[0054] Step 1: Install a climbing ladder and a bracket platform under the beam body where the tension and compression bearing is to be replaced;

[0055] Step 2: Layout and install the jacking equipment; According to the bearing capacity design of the tension and compression bearing to be replaced, determine the number of required PLC synchronous jacking equipment, and symmetrically arrange the hydraulic jacking devices around the tension and compression bearing to be replaced; Each PLC synchronous jacking equipment includes multiple jacks and a control device;

[0056] Step 3: Conduct a trial jacking of the jacks; The synchronous error during the entire jacking process should be kept less than 0.5 mm. Once the position error is greater than 0.5 mm, the control system immediately closes the hydraulic control check valve. After each round of jacking is completed, analyze the displacement of each oil cylinder and the pressure of the jacks at any time. If there are any abnormalities, deal with them in a timely manner; After the main beam is jacked up for one stroke, measure the elevation values of each elevation observation point, obtain the jacking height of each observation point, and calculate the synchronous error;

[0057] The jacking system uses dual control of displacement and jacking pressure as the basis for jacking control. Immediately after installation, conduct a trial adjustment of each jack. Before jacking, single and uniformly debug the normal operation of each control system to ensure normal progress during jacking; After the jacks are debugged, conduct a pressure test jacking, and carefully check whether there are any phenomena in the structure under the placement position of the jacks that are different from those before jacking. If so, immediately find out the reasons carefully, deal with them in a timely manner, and then conduct formal jacking (immediately organize a communication meeting after unloading, coordinate and handle the problems that occur in a timely manner, and clarify whether there are any matters that need to be emphasized and improved again in the process control of the organization structure, information transmission and feedback, etc.).

[0058] Step 4: Install the upper cushion plate assembly, upper tooling assembly and lower tooling assembly on the temporary bearing tooling:

[0059] (4.1) Detect the original structure steel bars and prestressed steel bars, find out the distribution of steel bars in the anchorage area, and avoid blindly constructing too many waste holes. The waste holes should be repaired in time with the original structure concrete grade or high-strength polymer concrete; The anchor bolts are M26 high-strength anchor bolts, and the implantation depth into the original structure is not less than 30 cm. Use a special electric hammer for drilling and a core drill according to the type of designed anchor bolts. The drilling on the anchorage steel plate should coincide with the on-site drilling lofting results of the original structure. Control the drilling depth during drilling to prevent damage to the original prestress. The drilling of the upper and lower anchorage steel plates should be carried out according to the on-site hole position layout after all the rebar holes of the beam body structure are drilled;

[0060] (4.2) After cleaning the holes according to the design requirements, post-install the anchor bars; after injecting the post-installation adhesive into the holes, slowly and rotationally insert the anchor bolts that have been cleaned with acetone and fully dried into the blind holes in a clockwise direction while rotating and inserting until the specified depth is reached. When installing the anchor bars, the installation shall be carried out strictly according to the required depth. Before the post-installation adhesive cures, the installed anchor bolts shall not be disturbed. After the post-installation adhesive has completely cured, conduct a pull-out test on the installed steel bars, and the test results must meet the design and specification requirements;

[0061] (4.3) Each component of the temporary bearing tooling is processed in the factory and meets the requirements of secondary welds. The upper and lower anchor backing plates are drilled according to the actual on-site hole positions, and the hole drilling is carried out on-site with a template. After the temporary bearing steel pads are welded in the factory, they are transported to the pier top as a whole and transferred to the construction area with a crane and a chain block for hole alignment and installation. Each single temporary bearing is installed in three sections. When installing, first install the lower tooling component, then the upper backing plate component and the upper tooling component;

[0062] Step 5: Officially jack up and install the middle tooling component of the temporary bearing tooling at the same time; use PLC synchronous jacking. During the jacking process, set the jacking rate and height of each point through a central control computer to achieve synchronous and coordinated jacking of the beam body, reducing the possibility of bridge displacement during jacking. In this jacking, each standard jacking stroke shall not be greater than 2 mm, and the jacking speed is set at 2 - 4 mm / min;

[0063] During the jacking process, it shall be slowly, synchronously jacked up in stages and levels, and a special person shall check the void situation of the upper steel plate of the bearing at any time during the jacking process; when jacked up to the predetermined height, install the middle tooling component of the temporary bearing tooling;

[0064] During the jacking process, strictly control the transverse jacking height difference between adjacent bearings within 0.1 mm. After each round of jacking is completed, sort out and analyze the displacement of each oil cylinder and the pressure of the jacks at any time, and check the jacking height through the control points.

[0065] During the official jacking process, it shall be carried out according to the following procedures and records shall be made:

[0066] a Operation: Load and jack up according to the preset load;

[0067] b Observation: Each observation point shall promptly report the observation situation;

[0068] c Measurement: Each measurement point shall earnestly carry out the measurement work and promptly report the measurement data;

[0069] d Verification: Report the data to the on-site leading group and compare the difference between the measured data and the theoretical data;

[0070] e Analysis: If there are data deviations, all relevant parties shall earnestly analyze and promptly make adjustments;

[0071] f Decision: Recognize the current working status and decide on the next operation.

[0072] Step 6: First system conversion and removal of old bearings;

[0073] After the installation of the temporary bearing tooling is completed, perform the system conversion: Adjust the lifting height of the upper structure of the bridge through the PLC synchronous jacking equipment. After the temporary bearing tooling is fully stressed, remove the old bearings with existing diseases; Chisel the original bearing padstone, cut off the steel bars on the upper part of the padstone, and retain the embedded bolts on the upper steel plate as the connecting bolts for the new bearings; After the padstone concrete is chiseled, cut off the anchor bolts of the lower steel plate. After loosening the bolts of the upper steel plate, take out the old bearings with existing diseases as a whole to complete the first system conversion of the old and new bearings;

[0074] Step 7: Install new bearings;

[0075] Lift the new bearing to the pier top and use a chain block to transport it to the bottom of the beam. The lower seat plate of the new bearing is connected and fixed with bolts. The steel bars of the new bearing padstone are welded with portal bars, moved into place using a horizontal trolley, and sleeved on the upper embedded screw of the original bearing, then tighten the nuts for fixation; At the same time, check whether the installation position of the new bearing is horizontal, and review whether its bearing center line and diagonal line comply with the design requirements.

[0076] Step 8: Formwork erection and grout pouring;

[0077] Re-pour the chiseled part of the padstone concrete in Step 5 with self-leveling bearing special grout (C60 high-strength grout). The allowable deviation of the top elevation of the bearing padstone shall not exceed ±2mm, the height difference at the four corners of the top surface shall not exceed 1mm, and the axial deviation shall not exceed 5mm; During pouring, it must be ensured that the new bearing is in close contact with the upper and lower structures without any voids; After pouring, do a good job in the subsequent maintenance work;

[0078] Step 9: Lower the beam;

[0079] After the strength of the newly poured grout reaches 100% of the design value, adjust the pre-deviation of the bearing, use the PLC synchronous jacking equipment to gradually and slowly relieve the pressure, transfer the weight of the beam from the temporary bearing to the newly installed bearing, and gradually complete the second system conversion; During the pressure relief process, pay attention to observing the stress state of the bearing, the close contact of the contact surface, and the displacement of the new bearing after the beam is lowered; After all the monitoring data and the normal operation of the new bearing on site, remove the PLC synchronous jacking equipment and clean up the site.

[0080] During the above construction process, the following items need to be monitored synchronously:

[0081] (1) Mid-span stress monitoring;

[0082] (2) Bridge deck elevation;

[0083] (3) Temporary support reaction force;

[0084] (4) Cable forces of the 5 stay cables closest to the support.

[0085] The monitoring frequency should be determined according to the actual on-site situation, but it should be no less than once a week.

[0086] This construction method is particularly applicable to:

[0087] 1. Long-span cable-stayed bridges, and due to the influence of live loads or temperature loads, the superstructure of the bridge continuously expands and contracts along the longitudinal axis of the bridge with a relatively large expansion and contraction amplitude;

[0088] 2. When the tensile and compressive support is significantly in tension and there is no space on the bridge deck to arrange counterweight loads;

[0089] 3. When the traffic flow of the cable-stayed bridge is large and traffic control or traffic restrictions cannot be carried out;

[0090] 4. This construction method can be referred to for some steel box girder cable-stayed bridges and some rigid frame bridges.

[0091] This solution is a construction technology for replacing the tensile and compressive supports of a cable-stayed bridge without interrupting traffic, developed on the basis of years of engineering practice. On this basis, a construction method for replacing the tensile and compressive supports of a cable-stayed bridge without interrupting traffic has been summarized, and this construction method has been successfully promoted and applied in the replacement of the tensile and compressive supports of the Jingzhou Yangtze River Highway Bridge.

[0092] The above shows and describes 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 by the above embodiments. What is described in the above embodiments and the specification only illustrates the structural relationship and principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A temporary bearing tooling for replacing the tensile and compressive bearings of a bridge, characterized in that: it includes an upper backing plate assembly, an upper tooling assembly, a middle tooling assembly, a lower tooling assembly and connecting bolts; The upper backing plate assembly includes an upper backing plate anchoring steel plate (0) arranged at the topmost, an upper backing plate connecting steel plate (1) located on the lower end face of the upper backing plate anchoring steel plate, L-shaped upper backing plate clamping plates (4), and upper backing plate polytetrafluoroethylene plates (5). There are two L-shaped upper backing plate clamping plates (4), symmetrically and fixedly arranged on both sides of the lower end face of the upper backing plate connecting steel plate (1). There are two upper backing plate polytetrafluoroethylene plates (5), symmetrically and fixedly arranged at the inner horizontal end faces of each L-shaped upper backing plate clamping plate (4); The upper tooling assembly includes an upper tooling polytetrafluoroethylene plate (2), an upper tooling upper steel plate (3) located on the lower end face of the upper tooling polytetrafluoroethylene plate, an upper tooling lower backing plate (7) located below the upper tooling upper steel plate, an upper tooling transverse stiffening plate (8), and an upper tooling longitudinal stiffening plate (6). The upper tooling transverse stiffening plate (8) is fixedly arranged between the upper tooling upper steel plate and the upper tooling lower backing plate. There are two upper tooling longitudinal stiffening plates (6), symmetrically and fixedly arranged on both sides of the upper tooling transverse stiffening plate (8); The middle tooling assembly includes a middle tooling upper backing plate (7’), a middle tooling longitudinal stiffening plate (9), a middle tooling transverse stiffening plate (10), and a middle tooling lower backing plate (11). The middle tooling transverse stiffening plate (10) is fixedly arranged between the middle tooling upper backing plate (7’) and the middle tooling lower backing plate. There are two middle tooling longitudinal stiffening plates (9), symmetrically and fixedly arranged on both sides of the middle tooling transverse stiffening plate (10); The lower tooling assembly includes a lower tooling upper backing plate (11’), a lower tooling transverse stiffening plate (17), a lower tooling longitudinal stiffening plate (13), and a lower tooling lower backing plate (15). The lower tooling transverse stiffening plate (17) is fixedly arranged between the lower tooling upper backing plate (11’) and the lower tooling lower backing plate. There are two lower tooling longitudinal stiffening plates (13), symmetrically and fixedly arranged on both sides of the lower tooling transverse stiffening plate (17); The upper tooling polytetrafluoroethylene plate (2) and the upper tooling upper steel plate (3) are integrally embedded in the stepped grooves formed by the L-shaped upper backing plate clamping plates (4) on the left and right sides; The upper tooling lower backing plate (7) and the middle tooling upper backing plate (7’) are fixedly connected; The middle tooling lower backing plate (11) and the lower tooling upper backing plate (11’) are fixedly connected; The upper backing plate anchoring steel plate (0) and the upper backing plate connecting steel plate (1) are integrally anchored to the beam bottom by means of planting connecting bolts, and the nuts on the connecting bolts are tightened; The lower tooling lower backing plate (15) is anchored to the top surface of the capping beam or the connecting beam by means of planting connecting bolts, and the nuts on the connecting bolts are tightened; When the temporary bearing tooling is subjected to an upward pulling force, the connecting bolts planted in the lower tooling must meet the pulling requirements. When the temporary bearing tooling is subjected to a downward pressure, the stiffening plates in the tooling must meet the compressive stress requirements; The surfaces of the upper tooling polytetrafluoroethylene plate (2) and the upper backing plate polytetrafluoroethylene plate (5) are both coated with lubricating oil; The number of the upper tooling assemblies and the middle tooling assemblies is not less than one.

2. The temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: On both sides of the upper end of the lower tooling longitudinal stiffening plate (13), there is a lower tooling upper inclined stiffening plate (12) between each of them and the lower end surface of the lower tooling lower backing plate (15); on both sides of the lower end of the lower tooling longitudinal stiffening plate (13), there is a lower tooling lower inclined stiffening plate (14) between each of them and the upper end surface of the lower tooling lower backing plate (15).

3. The temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: The lubricating oil is silicone grease oil.

4. The temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: The lower backing plate (7) of the upper tooling and the upper backing plate (7’) of the middle tooling are fixedly connected by connecting bolts.

5. The temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: The lower backing plate (11) of the middle tooling and the upper backing plate (11’) of the lower tooling are fixedly connected by connecting bolts.

6. The temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: The upper backing plate connecting steel plate (1) and the upper backing plate buckle plate (4) are connected by groove welding.

7. The replacement construction method of the temporary bearing tooling for replacing the tensile and compressive bearings of a bridge according to claim 1, characterized in that: It includes the following steps: The first system conversion, bearing replacement, the second system conversion; using the PLC synchronous jacking system, the upper structure of the bridge is integrally lifted by 3 - 5 mm until the temporary bearing is stressed; After the temporary bearing operates normally, remove the temporary bearing, chisel the bearing pad stone to replace the bearing. After the bearing replacement is completed, conduct the second system conversion, and use the PLC synchronous jacking system to lower the box girder on the temporary bearing as a whole back to the permanent bearing; Remove the temporary bearing, and the replacement of the tensile and compressive bearing is completed. Step 1: Install the ladder and bracket platform under the beam body where the tensile and compressive bearing is to be replaced; Step 2: Layout and installation of the jacking equipment; according to the bearing capacity design of the tensile and compressive bearing to be replaced, determine the number of required PLC synchronous jacking equipment, and symmetrically arrange the hydraulic jacking devices around the replaced tensile and compressive bearing; each PLC synchronous jacking equipment includes multiple jacks and control devices; Step 3: Trial jacking of the jacks; the synchronous error during the entire jacking process should be kept less than 0.5 mm. Once the position error is greater than 0.5 mm, the control system immediately closes the hydraulic check valve; after each round of jacking is completed, analyze the displacement of each oil cylinder and the pressure of the jacks at any time. If there is any abnormality, deal with it in time; after the main beam jacks up one stroke, measure the elevation values of each elevation observation point, obtain the jacking height of each observation point, and calculate the synchronous error; The jacking system uses dual control of displacement and jacking pressure as the basis for jacking control; immediately adjust each jack after installation. Before jacking, single and uniformly debug the normal operation of each control system to ensure the normal progress during jacking; after the jacks are debugged, conduct pressure trial jacking, and carefully check whether the structure under the placement position of the jacks is different from the top... Before jacking, if any abnormal phenomena exist, immediately find out the reasons carefully, handle them in time, and then carry out the formal jacking; Step 4: Installation of the upper cushion plate assembly, upper tooling assembly and lower tooling assembly on the temporary bearing tooling: (4.1) Detect the original structure steel bars and prestressed steel bars, find out the distribution of steel bars in the anchorage area, avoid too many waste holes caused by blind construction, and repair the waste holes in time with the original structure concrete grade or high-strength polymer concrete; The anchor bolts shall be M26 high-strength anchor bolts, and the implantation depth into the original structure shall not be less than 30 cm. Use a special electric hammer and core drill according to the type of designed anchor bolts; The drilling on the anchoring steel plate shall be consistent with the on-site drilling lofting results of the original structure. Control the drilling depth during drilling to prevent damage to the original prestress; The drilling of the upper and lower anchoring steel plates shall be carried out according to the on-site hole positions after all the rebar planting holes of the beam body structure are drilled. (4.2) After clearing the holes according to the design requirements, carry out rebar planting; After injecting the rebar planting glue into the holes, immediately and slowly rotate and insert the anchor bolts that have been cleaned with acetone and fully dried into the blind holes, and insert them while rotating clockwise until the specified depth is reached; When planting anchor bars, they shall be installed strictly according to the required depth; Before the rebar planting glue cures, the planted anchor bolts shall not be disturbed; After the rebar planting glue is completely cured, carry out a pull-out test on the planted steel bars, and the test results must meet the design and specification requirements. (4.3) Each component of the temporary bearing tooling is processed in the factory to meet the requirements of secondary welds. The upper and lower anchor backing plates are drilled according to the actual on-site hole positions by using a template on-site. After the steel pads of the temporary bearing are welded in the factory, they are transported to the pier top as a whole and transferred to the construction area by a crane and a chain block for hole alignment and installation. Each single temporary bearing is installed in three sections. When installing, first install the lower tooling assembly, and then the upper cushion plate assembly and the upper tooling assembly. Step 5: Carry out the formal jacking and install the middle tooling assembly of the temporary bearing tooling at the same time; Adopt PLC synchronous jacking. During the jacking process, set the jacking rate and height of each point through a central control computer to realize synchronous and coordinated jacking of the beam body and reduce the possibility of bridge displacement during jacking; In this jacking, each standard jacking stroke shall not be greater than 2 mm, and the jacking speed is set at 2 - 4 mm / min. During the jacking process, it shall be carried out slowly, in stages and synchronously, and a special person shall check the void situation of the upper steel plate of the bearing at any time during the jacking process; When the predetermined height is reached, install the middle tooling assembly of the temporary bearing tooling. During the jacking process, strictly control the transverse jacking height difference between adjacent bearings within 0.1 mm; After each round of jacking is completed, sort out and analyze the displacement of each oil cylinder and the pressure of the jack at any time, and check the jacking height through the control points. For the formal jacking, it must be carried out according to the following procedures and records shall be made: a. Operation: Load and jack according to the preset load. b. Observation: Each observation point shall promptly reflect the observation situation. c. Measurement: Each measurement point shall earnestly do a good job in measurement and promptly reflect the measurement data. d. Checking: Report the data to the on-site leading group and compare the difference between the measured data and the theoretical data. e. Analysis: If there are data deviations, all relevant parties shall earnestly analyze and adjust in time. f Decision: Recognize the current working status and decide on the next operation; Step 6: First system conversion and removal of old bearings; After the installation of the temporary bearing tooling is completed, perform the system conversion: Use the PLC synchronous jacking equipment to adjust the lifting height of the upper structure of the bridge. After the temporary bearing tooling is fully stressed, remove the old bearings with original diseases; Chisel the original bearing padstone, cut the steel bars on the upper part of the padstone, and retain the embedded bolts on the upper steel plate as the connecting bolts for the new bearings; After the padstone concrete is chiseled, cut the anchor bolts of the lower steel plate. After loosening the bolts of the upper steel plate, take out the old bearings with original diseases as a whole to complete the first system conversion of the old and new bearings; Step 7: Install new bearings; Lift the new bearing to the top of the pier and use a chain block to transfer it to the bottom of the beam; Connect and fix the lower seat plate of the new bearing with bolts. Weld the steel bars of the new bearing padstone with portal bars, move it into place using a horizontal trolley, and then sleeve the embedded screw rod on the upper part of the original bearing and tighten the nuts; At the same time, check whether the installation part of the new bearing is horizontal, and review whether its bearing center line and diagonal line comply with the design requirements; Step 8: Formwork erection and grout pouring; Re-pour the chiseled part of the padstone concrete in Step 5 with self-leveling bearing special grout. The allowable deviation of the top elevation of the bearing padstone shall not exceed ±2mm, the height difference at the four corners of the top surface shall not exceed 1mm, and the axial deviation shall not exceed 5mm; During pouring, it is necessary to ensure that the new bearing is in close contact with the upper and lower structures and there shall be no void phenomenon; After pouring, do a good job in the later maintenance work; Step 9: Lower the beam; After the strength of the newly poured grout reaches 100% of the design value, adjust the pre-deviation of the bearing, use the PLC synchronous jacking equipment to gradually and slowly relieve the pressure, transfer the weight of the beam from the temporary bearing to the newly installed bearing, and gradually complete the second system conversion; During the pressure relief process, pay attention to observing the stress state of the bearing, the close contact of the contact surface, and the displacement of the new bearing after lowering; After all the monitoring data and the normal operation of the new bearing on site, remove the PLC synchronous jacking equipment and clean up the site.

8. The replacement construction method of the temporary bearing tooling for bridge tension and compression bearing replacement according to claim 7, characterized in that: The following items need to be monitored synchronously during the construction process; (1) Mid-span stress monitoring; (2) Bridge deck elevation; (3) Reaction force of the temporary bearing; (4) Cable forces of the 5 stay cables closest to the bearing; The monitoring frequency should be based on the actual situation on site, but it should be no less than once a week.

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