A method for constructing a main bridge steel structure

Abstract

The application discloses a main bridge steel structure construction method and relates to the technical field of bridge construction. The specific steps comprise the following steps: dividing regions, installing baffle plates and pier columns, installing steel pipe piles and platform support columns, installing inter-column supports and sliding beams to form sliding tracks, repeatedly constructing the south bank, completing platform support covering a river, installing lower chord rods and lower bridge decks, installing upper chord rods and upper bridge decks, installing upper-layer cantilevers and lower-layer cantilevers, assembling sliding units, repeatedly assembling sliding units until closure, hoisting the last sliding unit and completing installation of the main bridge steel structure. The construction method can reduce operation risks, shorten construction period, save materials and reduce costs.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, and more specifically to a method for constructing the steel structure of a main bridge. Background Technology

[0002] From the perspective of the entire physical structure of the bridge, the approach bridge abutments at both ends are the dividing points between the route and the abutments. The part of the bridge spanning major obstacles (such as river channels) is called the main bridge. Existing bridges use steel structures as the main supporting structure, and the bridge deck of steel structure bridges needs to be constructed to increase the physical performance of the bridge.

[0003] Currently, the existing construction methods for the main bridge steel structure employ incremental launching and sliding construction techniques. Due to the main bridge's design having a 2.5% longitudinal slope in both directions, there is a 2.5m height difference between the two ends of the main bridge and its center. Using the existing incremental launching method requires employing a heightened launching device to overcome this height difference, but this will also increase the risks during the launching and beam lowering processes.

[0004] Therefore, how to provide a construction method for the main bridge steel structure that reduces operational risks, shortens the construction period, saves materials, and reduces costs is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a construction method for the main bridge steel structure, which aims to solve one of the problems in the above-mentioned background art, and achieve low operational risk, shortened construction period, material saving and cost reduction.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A construction method for the main bridge steel structure, the construction method includes:

[0008] Step 1: Construction preparation. On the north bank, the crawler crane travel area and the assembly platform area are divided. The assembly platform area is leveled and compacted.

[0009] Step 2: Install baffles in the assembly platform area, and install piers in the water at a predetermined distance from the baffles on the north bank;

[0010] Step 3: Use a crawler crane with a vibratory hammer to install steel pipe piles in the assembly platform area, and then use a crawler crane to install platform support frames in the water between the piers and the baffle. Multiple steel pipe piles are set in the assembly platform area, and multiple platform support frames are set in parallel in the water.

[0011] Step 4: Use a crawler crane to install sliding beams and distribution beams between the baffle and the platform support frame. Lay galvanized steel planks on the distribution beams, and then set two sliding beams in parallel on the galvanized steel planks to form a sliding track.

[0012] Step 5: Use a floating crane to vibrate and sink the platform support frame in the water, and use the floating crane to hoist the inter-column supports and sliding beams between the platform support frames on the water surface. The sliding beams are set in two sections, which are connected to the two platform support frames to form a sliding track. The two platform support frames are connected to each other and between the platform support frames and the piers through the inter-column supports.

[0013] Step Six: Install piers in the center of the river. Use a floating crane to install multiple platform support frames from the bank to the piers in the center of the river. Set up two sections of sliding beam to connect all the platform support frames to form a sliding track. The platform support frames are connected to each other and to the piers through inter-column supports.

[0014] Step 7: Repeat steps 1 to 6 above to complete the installation of the retaining wall, piers, steel pipe piles, platform support frame and sliding track on the south bank in sequence. Complete the installation of the platform support frame that spans the entire river. Connect the platform support frames with each other and between the platform support frames and the piers through the inter-column supports. Complete the installation of the sliding track.

[0015] Step 8: Use a total station for layout and positioning. Set up positioning blocks and jacks above the sliding beam in advance, and place the sliding shoe on the sliding track in the assembly platform area. Use channel steel for temporary fixation. Use a crawler crane to lift the lower chord and install it on one side of the sliding track. Use jacks to adjust the installation elevation. Then use a total station to further verify the installation position of the lower chord. If there is any deviation, make fine adjustments. Repeat the installation of the second section of the lower chord below the sliding beam. After the installation and positioning are completed, use temporary support plates to symmetrically weld and fix the two sections of the lower chord.

[0016] Step 9: Repeat step 8 to continue installing the lower chord on the other side of the sliding track;

[0017] Step 10: Use a crawler crane to lift the lower bridge deck, which is positioned between the lower chords on both sides;

[0018] Step 11: Install round tubes next to the lower chord members, with the number of round tubes corresponding to the number of lower chord members. After supporting and fixing, install the web members.

[0019] Step 12: Continue to install temporary supports on the distribution beam for the installation and positioning of the truss and the upper chord. The temporary supports consist of a cantilevered steel beam, on which the upper chord is placed.

[0020] Step 13: Install the upper bridge deck between the two upper chord members;

[0021] Step Fourteen: After removing the temporary supports on the platform, use a crawler crane to install the lower cantilever, which is connected to the lower chord.

[0022] Step 15: Use a crawler crane to install the upper cantilever on the same side, and connect the upper cantilever to the upper chord;

[0023] Step 16: Repeat steps 14 and 15 to install the upper and lower cantilever on the other side;

[0024] Step 17: The upper and lower cantilevered sections on both sides, as well as the upper and lower bridge decks, extend towards the center of the river to form the first sliding unit. After the first sliding unit completes assembly, welding, and testing, it slides forward. During the sliding process, the horizontal position is adjusted using a horizontal hydraulic cylinder. Then, the next sliding unit is assembled on the assembly platform on the opposite bank.

[0025] Step 18: Perform the third sliding motion and use the same method to slide the assembled sliding unit to the position extending to the center of the river;

[0026] Step 19: Repeat the assembly of the sliding units on both banks;

[0027] Step 20: After the sliding units on the north and south banks are assembled, they will finally come into contact near the middle pier. It is necessary to conduct a position analysis before the final contact. If any deviation occurs, it will be corrected by adjusting the horizontal hydraulic cylinder. After the floating crane lifts the last sliding unit, the main bridge steel structure installation is completed.

[0028] Furthermore, before installing the platform support frame, the installation should proceed only after the test pile bearing capacity meets the requirements, using the driving depth and penetration of the test pile as dual control indicators.

[0029] Furthermore, when it is necessary to adjust the elevation of the upper chord, the adjustment is carried out by adding steel pads to the steel beam.

[0030] Furthermore, the lower bridge deck is composed of inverted T-shaped transverse beams and orthogonal irregular bridge panels.

[0031] Furthermore, the sliding unit uses a hydraulic sliding system to slide forward.

[0032] As can be seen from the above technical solution, compared with the prior art, this invention discloses a construction method for the main bridge steel structure. The installation of the main bridge steel structure adopts "hydraulic synchronous cumulative sliding unit construction technology," while considering the influence of longitudinal slope, and the closure is completed by cumulative sliding units from the north and south banks towards the middle. The advantages of this construction method are: the jacking method used in the construction of the main bridge steel structure can build large-segment bridges with simple equipment, resulting in lower construction costs, smooth construction, and no noise. It can be used on bridges with deep water, high piers, and slopes with the same curvature as in this project; segmented manufacturing and continuous operation result in good structural integrity, eliminating the need for large lifting equipment on site, and the length of the construction segments can be selected according to the assembly site conditions and the reasonable location of the segments; the bridge segments are assembled in the same site, which facilitates construction management and improves construction conditions; the continuous automatic jacking construction method allows the steel beams to be assembled centrally on a fixed assembly platform, greatly reducing the risk of hoisting and ensuring the safety of hoisting and welding; there is no need to set up temporary assembly platforms along the bridge, saving temporary assembly platform materials, shortening the construction period, and reducing project costs. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 This invention provides a schematic diagram of the steps involved in the construction of a main bridge steel structure.

[0035] Figure 2A-2W This is a schematic diagram of the construction process of a main bridge steel structure construction method provided by the present invention. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] See Figure 1 and 2A -2W, This invention discloses a construction method for a main bridge steel structure, the construction method including:

[0038] Step 1: Construction preparation. On the north bank, the crawler crane travel area and the assembly platform area are divided. The assembly platform area is leveled and compacted.

[0039] Step 2: Install baffles in the assembly platform area, and install piers in the water at a predetermined distance from the baffles on the north bank;

[0040] Step 3: Use a crawler crane and vibratory hammer to install steel pipe piles in the assembly platform area. Then, use a crawler crane to install platform support frames in the water between the pier and the baffle. Multiple steel pipe piles are set in the assembly platform area, and multiple platform support frames are set in parallel in the water. In this embodiment, a total of 16 platform support frames are set.

[0041] Step 4: Use a crawler crane to install sliding beams and distribution beams between the baffle and the platform support frame. Lay galvanized steel planks on the distribution beams, and then set two parallel sliding beams on the galvanized steel planks to form a sliding track; the galvanized steel planks are 4000×250×50mm in size.

[0042] Step 5: Use a floating crane to vibrate and sink the platform support frame in the water, and use the floating crane to hoist the inter-column supports and sliding beams between the platform support frames on the water surface. The sliding beams are set in two sections, which are connected to the two platform support frames to form a sliding track. The two platform support frames are connected to each other and between the platform support frames and the piers through the inter-column supports.

[0043] Step Six: Install piers in the center of the river. Use a floating crane to install multiple platform support frames from the bank to the piers in the center of the river. Set up two sections of sliding beam to connect all the platform support frames to form a sliding track. The platform support frames are connected to each other and to the piers through inter-column supports.

[0044] Step 7: Repeat steps 1 to 6 above to complete the installation of the retaining wall, piers, steel pipe piles, platform support frame and sliding track on the south bank in sequence. Complete the installation of the platform support frame that spans the entire river. Connect the platform support frames with each other and between the platform support frames and the piers through the inter-column supports. Complete the installation of the sliding track.

[0045] Step 8: Use a total station for layout and positioning. Set up positioning blocks and jacks above the sliding beam in advance, and place the sliding shoe on the sliding track in the assembly platform area. Use channel steel for temporary fixation. Use a crawler crane to lift the lower chord and install it on one side of the sliding track. Use jacks to adjust the installation elevation. Then use a total station to further verify the installation position of the lower chord. If there is any deviation, make fine adjustments. Repeat the installation of the second section of the lower chord below the sliding beam. After the installation and positioning are completed, use temporary support plates to symmetrically weld and fix the two sections of the lower chord.

[0046] Step 9: Repeat step 8 to continue installing the lower chord on the other side of the sliding track;

[0047] Step 10: Use a crawler crane to lift the lower bridge deck, which is positioned between the lower chords on both sides;

[0048] Step 11: Install round tubes next to the lower chord members, with the number of round tubes corresponding to the number of lower chord members. After supporting and fixing, install the web members; in this embodiment, 10 round tubes are installed.

[0049] Step 12: Continue to install temporary supports on the distribution beam for the installation and positioning of the truss and the upper chord. The temporary supports consist of a cantilevered steel beam, on which the upper chord is placed. In this embodiment, the cantilever length of the steel beam is 1.2m.

[0050] Step 13: Install the upper bridge deck between the two upper chord members;

[0051] Step Fourteen: After removing the temporary supports on the platform, use a crawler crane to install the lower cantilever, which is connected to the lower chord.

[0052] Step 15: Use a crawler crane to install the upper cantilever on the same side, and connect the upper cantilever to the upper chord;

[0053] Step 16: Repeat steps 14 and 15 to install the upper and lower cantilever on the other side;

[0054] Step 17: The upper and lower cantilevered sections on both sides, as well as the upper and lower bridge decks, extend towards the center of the river to form the first sliding unit. After the first sliding unit completes assembly, welding, and testing, it slides forward. During the sliding process, the horizontal position is adjusted using a horizontal hydraulic cylinder. Then, the next sliding unit is assembled on the assembly platform on the opposite bank.

[0055] Step 18: Perform the third sliding motion and use the same method to slide the assembled sliding unit to the position extending to the center of the river;

[0056] Step 19: Repeat the assembly of the sliding units on both banks;

[0057] Step 20: After the sliding units on the north and south banks are assembled, they will finally come into contact near the middle pier. It is necessary to conduct a position analysis before the final contact. If any deviation occurs, it will be corrected by adjusting the horizontal hydraulic cylinder. After the floating crane lifts the last sliding unit, the main bridge steel structure installation is completed.

[0058] In this embodiment, before installing the platform support frame, the bearing capacity of the test piles must meet the requirements, and the driving depth and penetration of the test piles should be used as dual control indicators before installation.

[0059] In this embodiment, when it is necessary to adjust the elevation of the upper chord, the adjustment is carried out by adding a steel pad to the steel beam.

[0060] In this embodiment, the lower bridge deck is composed of inverted T-shaped transverse beams and orthogonal irregular bridge panels, which are assembled on-site into a whole bridge panel before installation. The dimensions are 8.7m × 10m.

[0061] In this embodiment, the sliding unit uses a hydraulic sliding system to slide forward.

[0062] In this embodiment, the main bridge structure is divided into 26 segments, 14 on the south bank and 12 on the north bank. Two segments are assembled and slid forward each time, in 7 steps, with each slide distance being approximately 20m. Each segment includes a 10m main truss and upper and lower bridge decks.

[0063] A sliding assembly platform measuring 23.7m long and 25.7m wide is set up on the side of the bridge pier. The assembly platform is mainly supported by a lattice-type temporary support structure. At the same time, two sliding tracks are set up 4.6m on both sides of the center line of the main bridge. The spacing between the platform support frames is 7.56m, and the spacing between the pier column and the steel pipe pile is adjusted to 8m.

[0064] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0065] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A construction method for the steel structure of a main bridge, characterized in that, Construction methods include: Step 1: Construction preparation. On the north bank, the crawler crane travel area and the assembly platform area are divided. The assembly platform area is leveled and compacted. Step 2: Install baffles in the assembly platform area, and install piers in the water at a predetermined distance from the baffles on the north bank; Step 3: Use a crawler crane with a vibratory hammer to install steel pipe piles in the assembly platform area, and then use a crawler crane to install platform support frames in the water between the piers and the baffle. Multiple steel pipe piles are set in the assembly platform area, and multiple platform support frames are set in parallel in the water. Step 4: Use a crawler crane to install sliding beams and distribution beams between the baffle and the platform support frame. Lay galvanized steel planks on the distribution beams, and then set two sliding beams in parallel on the galvanized steel planks to form a sliding track. Step 5: Use a floating crane to vibrate and sink the platform support frame in the water, and use the floating crane to hoist the inter-column supports and sliding beams between the platform support frames on the water surface. The sliding beams are set in two sections, which are connected to the two platform support frames to form a sliding track. The two platform support frames are connected to each other and between the platform support frames and the piers through the inter-column supports. Step Six: Install piers in the center of the river. Use a floating crane to install multiple platform support frames from the bank to the piers in the center of the river. Set up two sections of sliding beams to connect all the platform support frames to form a sliding track. The platform support frames are connected to each other and to the piers through inter-column supports. Step 7: Repeat steps 1 to 6 above to complete the installation of the retaining wall, piers, steel pipe piles, platform support frame and sliding track on the south bank in sequence. Complete the installation of the platform support frame that spans the entire river. Connect the platform support frames with each other and between the platform support frames and the piers through the inter-column supports. Complete the installation of the sliding track. Step 8: Use a total station for layout and positioning. Set up positioning blocks and jacks above the sliding beam in advance, and place the sliding shoe on the sliding track in the assembly platform area. Use channel steel for temporary fixation. Use a crawler crane to lift the lower chord and install it on one side of the sliding track. Use jacks to adjust the installation elevation. Then use a total station to further verify the installation position of the lower chord. If there is any deviation, make fine adjustments. Repeat the installation of the second section of the lower chord below the sliding beam. After the installation and positioning are completed, use temporary support plates to symmetrically weld and fix the two sections of the lower chord. Step 9: Repeat step 8 to continue installing the lower chord on the other side of the sliding track; Step 10: Use a crawler crane to lift the lower bridge deck, which is positioned between the lower chords on both sides; Step 11: Install round tubes next to the lower chord members, with the number of round tubes corresponding to the number of lower chord members. After supporting and fixing, install the web members. Step 12: Continue to install temporary supports on the distribution beam for the installation and positioning of the truss and the upper chord. The temporary supports consist of a cantilevered steel beam, on which the upper chord is placed. Step 13: Install the upper bridge deck between the two upper chord members; Step Fourteen: After removing the temporary supports on the platform, use a crawler crane to install the lower cantilever, which is connected to the lower chord. Step 15: Use a crawler crane to install the upper cantilever on the same side, and connect the upper cantilever to the upper chord; Step 16: Repeat steps 14 and 15 to install the upper and lower cantilever on the other side; Step 17: The upper and lower cantilevered sections on both sides, as well as the upper and lower bridge decks, extend towards the center of the river to form the first sliding unit. After the first sliding unit completes the assembly, welding, and testing, it slides forward. During the sliding process, the horizontal position is adjusted using a horizontal hydraulic cylinder. Then, the next sliding unit is assembled on the assembly platform on the opposite bank. Step 18: Perform the third sliding motion and use the same method to slide the assembled sliding unit to the position extending to the center of the river; Step 19: Repeat the assembly of the sliding units on both banks; Step 20: After the sliding units on the north and south banks are assembled, they will finally come into contact near the middle pier. It is necessary to conduct a position analysis before the final contact. If any deviation occurs, it will be corrected by adjusting the horizontal hydraulic cylinder. After the floating crane lifts the last sliding unit, the main bridge steel structure installation is completed.

2. The construction method for a main bridge steel structure according to claim 1, characterized in that, Before installing the platform support frame, the bearing capacity of the test piles must meet the requirements, and the driving depth and penetration of the test piles should be used as dual control indicators before installation.

3. The construction method for a main bridge steel structure according to claim 1, characterized in that, When it is necessary to adjust the elevation of the upper chord, the adjustment is carried out by adding steel pads to the steel beam.

4. The construction method for a main bridge steel structure according to claim 1, characterized in that, The lower bridge deck is composed of inverted T-shaped transverse beams and orthogonal irregular bridge panels.

5. The construction method for a main bridge steel structure according to claim 1, characterized in that, The sliding unit uses a hydraulic sliding system to slide forward.

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