Steel arch rib side-lying assembly jig structure and assembly method for long-span arch bridge

Abstract

The present invention provides a horizontally-mounted assembly jig structure for the steel arch rib of a long-span arch bridge. The steel arch rib is composed of at least one truss panel. The overall cross-section of the steel arch rib is arc-shaped and bent. The joints of adjacent truss panels are coplanar along the length direction of the arch bridge. A gusset plate is provided at the joint, and the gusset plates are arranged parallel to each other vertically. The jig structure is composed of a number of jig units connected in sequence. The jig units gradually increase in height from one side to the other side, and the jig units are assembled vertically near each gusset plate. The advantages of the present invention are as follows: for the horizontally-mounted assembly jig structure with gradually increasing height, the bottom layer of the frame is fixed, and the upper layers of the frames are movable structures. The jig structure is simple and convenient to operate; the assembly of each layer of truss panels can share the same set of ground sample benchmarks to control the alignment, and the positioning standards are unified, which is beneficial to the control of the assembly alignment.

Description

Technical Field

[0001] The present invention relates to the field of bridge construction, and particularly to a lateral horizontal assembly jig structure and an assembly method for a steel arch rib of a long-span arch bridge. Background Art

[0002] With the booming development of the national economy, more and more long-span arch bridges are being constructed and applied, especially emerging continuously in the complex geographical environment of mountainous areas. To enhance the lateral stiffness of the arch bridge, the X-shaped basket arch structure with bifurcated arch feet is often adopted in the design, from which an arch rib structure with two-way curves in the horizontal and vertical planes is derived, greatly increasing the processing difficulty. When the steel truss arch rib with a conventional parallel structure is assembled and manufactured in the factory, the control of the vertical curve is mainly considered. If the lateral horizontal assembly and manufacture are adopted, a horizontal assembly jig with the same height is set, and only the linear shape of a single curve needs to be adjusted. However, for the lateral horizontal assembly and manufacture of the arch rib segment with a two-way curve, further exploration and research are still needed. Summary of the Invention

[0003] The purpose of the present invention is to provide a lateral horizontal assembly jig structure and method for a steel arch rib of a long-span arch bridge.

[0004] To achieve the above purpose, the technical solution of the present invention is as follows:

[0005] A lateral horizontal assembly jig structure for a steel arch rib of a long-span arch bridge, characterized in that the steel arch rib is composed of at least one truss sheet, the overall cross-section of the steel arch rib is arc-shaped and bent, the truss sheet nodes of each segment of the steel arch rib are located in the same vertical plane, a gusset plate is provided at the node, the gusset plates are arranged parallel to each other in the vertical direction, the jig structure is composed of a number of jig monomers connected in sequence, the jig monomers gradually increase in height from one side to the other side, and the jig monomers are assembled in the vertical direction near each gusset plate.

[0006] Further, the jig monomer is made of section steel materials, the jig monomer is divided into at least one layer in the vertical direction, and the number of layers of the jig monomer matches the number of truss sheets of a node of the steel arch rib.

[0007] Further, the jig monomer includes a bottom frame body and an upper frame body, the bottom frame body is fixedly connected to the concrete hardened ground of the assembly site, the upper frame body is a movable structure, and the bottom frame body and the upper frame body are connected by bolts.

[0008] A lateral horizontal assembly method for a steel arch rib of a long-span arch bridge, characterized by including the following steps:

[0009] Step S1) On the assembled site with a hardened ground, according to the vertical arch axis shape and structural dimensions of the steel arch rib, comprehensively considering the segment length and weight, reducing the self-weight deformation of the horizontal assembly, avoiding the gusset plates, weld areas and segment joints, determine the placement position of the falsework along the vertical curve of the steel arch rib on the hardened ground, and draw a ground line on the hardened ground;

[0010] Step S2) According to the placement position of the falsework on the hardened ground, the planar arch axis shape and structural dimensions of the steel arch rib to be assembled, determine the manufacturing heights of the bottom frame and the upper frame;

[0011] Step S3) According to the manufacturing height and stress state of the falsework, manufacture the bottom frame and the upper frame according to the processing dimensions. According to the determined placement position and ground line, position and install the bottom frame on the hardened ground of the assembly site, and connect it firmly to the hardened ground with expansion bolts.

[0012] Step S4) Measure the elevation of the bottom frame, adjust the overall linear shape of the falsework by changing the size of the shim plate, measure and recheck the elevation and position coordinates of the frame again to ensure that the linear shape meets the precision requirements of the horizontal assembly of the steel arch rib;

[0013] Step S5) Assemble the arch rib truss slices in single pieces. The bottom truss slices and the upper truss slices share the same set of ground lines for single-piece assembly. After all the truss slices of each layer are assembled in slices, on the basis of retaining the bottom truss slices, install the movable upper frame on the bottom frame. The bottom frame and the upper frame are connected by connecting flanges;

[0014] Step S6) After measuring and adjusting the linear shape of the upper frame and rechecking it to be qualified, hoist the upper truss slices one by one in sequence. Align the gusset plates of the upper and lower arch rib trusses vertically, use a plumb line to match the ground line and recheck the linear shape, adjust the matching of the main chord pipe orifices and temporarily lock them. After the upper truss slices are positioned, install the connecting members between the upper and lower trusses, and weld all the connecting welds as required to complete the assembly and manufacture of the single limb structure of the double-layer truss arch rib.

[0015] The advantages of the present invention are as follows:

[0016] For the assembly and manufacture of the segments of the two-way curve steel arch rib of a long-span arch bridge, the horizontal assembly falsework structure with gradually increasing height, the bottom frame is fixed, and the upper frames are movable structures. The falsework structure is simple and easy to operate; the assembly of each layer of truss slices can share the same set of ground reference to control the linear shape, and the positioning standard is unified, which is beneficial to the control of the assembly linear shape.

[0017] The horizontal assembly falsework structure with gradually increasing height enables the gusset plates at each node on the main chord to be assembled in a vertical state, which is convenient for positioning and checking. It cleverly transforms the complex spatial linear shape and angle into a two-dimensional vertical plane, simplifies the operation difficulty, is beneficial to the linear shape control, and can effectively improve the linear shape precision and processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the elevation schematic diagram of the gradually increasing side - horizontal assembling falsework structure of the present invention;

[0019] Figure 2 This is the plan schematic diagram of the gradually increasing side - horizontal assembling falsework structure of the present invention;

[0020] Figure 3 This is the elevation schematic diagram of the side - horizontal assembling of the double - curve steel arch rib of the present invention;

[0021] Figure 4 This is the plan schematic diagram of the side - horizontal assembling of the double - curve steel arch rib of the present invention;

[0022] Figure 5 This is the elevation schematic diagram of the falsework of the present invention;

[0023] Figure 6 This is the plan schematic diagram of the falsework of the present invention seen from above.

[0024] Reference Signs:

[0025] 1 Falsework

[0026] 2 Hardened ground

[0027] 3 Ground line

[0028] 4 Steel arch rib

[0029] 401 Bottom truss member

[0030] 402 Upper truss member

[0031] 5 Main chord

[0032] 6 Gusset plate

[0033] 7 Section line

[0034] 8 Bottom frame

[0035] 9 Upper frame

[0036] 10 Connecting flange

[0037] 11 Lifting plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without making creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0039] This embodiment discloses a side - horizontal assembling falsework structure for the steel arch rib of a long - span arch bridge, asFigure 1 As shown, the steel arch rib 4 is composed of at least one truss segment. The overall cross-section of the steel arch rib 4 is arc-shaped and bent. The truss nodes of each segment of the steel arch rib 4 are located in the same vertical plane. A gusset plate 6 is provided at the node, and the gusset plates 6 are arranged parallel to each other in the vertical direction. The structure of the falsework 1 is composed of several falsework 1 units connected in sequence. The falsework 1 unit gradually increases in height from one side to the other side, and the falsework 1 unit is assembled vertically near each gusset plate 6.

[0040] The falsework 1 unit is made of steel section materials. The falsework 1 unit is divided into at least one layer in the vertical direction, and the number of layers of the falsework 1 unit matches the number of truss segments of a node of the steel arch rib 4.

[0041] The falsework 1 unit includes a bottom frame body 8 and an upper frame body 9. The bottom frame body 8 is fixedly connected to the concrete hardened ground 2 of the assembly site. The upper frame body 9 is a movable structure, and the bottom frame body 8 and the upper frame body 9 are connected by bolts.

[0042] During specific implementation, for a long-span basket arch bridge in a mountainous area, the arch axis elevation adopts a catenary curve, the calculated span is 340m, and the rise is 74m; the plane is in a basket shape, divided into an arch-foot bifurcation section and an arch-top merging section, and the half-span of the bifurcation section is connected by three cross beams; the whole vertical plane inclines inward by 3.48°, forming an X-shaped structure with arch-foot bifurcation, the center distance of the arch feet is 16m, and the center distance of the arch-top axis is 7m.

[0043] The height of the arch rib changes according to a 1.5-degree parabola, and the center height of the upper and lower chord pipes transitions from 10m at the arch feet to 5m at the arch top. The steel arch rib 4 is a two-way curve steel pipe truss structure, mainly composed of 8 main chord members 5 and related connecting members. There are 4 main chord members 5 each on the upper and lower sides, with a steel pipe specification of φ750×24mm. The steel pipe and the connecting member of the combined angle steel are welded by a gusset plate 6. Due to the large vertical dimension of the two-way curve steel arch rib 4, and the center distance between adjacent two main chord members 5 of a single-limb arch rib is only 3.8m, so the 3+1 continuous matching side-lying assembly manufacturing is carried out for the upstream and downstream single limbs, and the gradually increasing height side-lying assembly falsework 1 structure involved in the present invention is used for auxiliary processing.

[0044] The gradually increasing height side-lying assembly falsework 1 structure is composed of a plurality of falsework units 1 with different heights arranged in a certain order. Since there are only two layers of truss segments in the side-lying assembly of a single-limb steel arch rib 4 in this embodiment, the falsework 1 only includes two layers of frame bodies, that is, a fixed bottom frame body 8 and a movable upper frame body 9. The 3+1 continuous matching side-lying assembly manufacturing is carried out for the single-limb steel arch rib 4, and 4 segments are assembled in each round, and the disconnection is made at the segmentation line 7 position of the steel arch rib 4 segments.

[0045] The jig frames 1 are arranged in two rows along the transverse direction on the hardened ground 2. Each row of the jig frames 1 is arranged in an arc shape with a convex middle part. The height of each row of the jig frames 1 increases successively from one side to the other side. The single-limb steel arch rib 4 includes an upper truss plate 402 and a lower truss plate 401. The upper truss plate 402 and the lower truss plate 401 are arranged at an interval up and down. The upper truss plate 402 and the lower truss plate 401 are parallel to each other. The upper truss plates 402 and the lower truss plates 401 between the two rows of jig frames 1 are connected by gusset plates 6.

[0046] The jig frame 1 includes an upper frame body 9 and a lower frame body 8 which are connected successively up and down. An elevating plate 12 is arranged inside each of the upper frame body 9 and the lower frame body 8. The elevating plate 12 is connected with the upper frame body 9 and the elevating plate 12 is connected with the lower frame body 8 by locking bolts. A heightening plate 11 is arranged at the upper end of each elevating plate 12. The lower frame body 8 and the hardened ground 2 are fixedly connected by expansion bolts.

[0047] The upper frame body 9 and the lower frame body 8 are fixedly connected by a connecting flange 10.

[0048] The assembly of the long-span basket arch bridge in the mountain area includes the following steps:

[0049] Step S1) On the assembly site with the hardened ground 2, according to the vertical arch axis shape and structural dimensions of the steel arch rib 4, comprehensively considering the section length and weight, reducing the self-weight deformation of the horizontal assembly, avoiding the gusset plates 6, the weld areas and the section butt joints, determine the placement position of the jig frames 1 on the hardened ground 2 along the vertical curve of the steel arch rib 4, and draw a ground line 3 on the hardened ground 2;

[0050] Step S2) According to the placement position of the jig frames 1 on the hardened ground 2, the plane arch axis shape and structural dimensions of the steel arch rib 4 to be assembled, determine the manufacturing heights of the lower frame body 8 and the upper frame body 9;

[0051] Step S3) According to the manufacturing height and stress state of the jig frames 1, manufacture and complete the lower frame body 8 and the upper frame body 9 according to the processing dimensions. According to the determined placement position and the ground line 3, position and install the lower frame body 8 on the hardened ground 2 of the assembly site, and connect it firmly with the hardened ground 2 by expansion bolts.

[0052] Step S4) Measure the elevation of the lower frame body 8, adjust the overall linear shape of the jig frames 1 by changing the dimensions of the heightening plates 11, measure and recheck the elevation and position coordinates of the frame body again to ensure that the linear shape meets the precision requirements of the horizontal assembly of the steel arch rib 4;

[0053] Step S5) Assemble the arch rib truss slices one by one. The bottom truss slice 401 and the upper truss slice 402 share the same set of ground sample lines 3 for single-piece assembly. After all the truss slices of each layer are assembled separately, on the basis of retaining the bottom truss slice 401, install the movable upper frame 9 on the bottom frame 8. The bottom frame 8 and the upper frame 9 are connected by a connecting flange 10;

[0054] Step S6) After measuring and adjusting the alignment of the upper frame 9 and passing the review, hoist the upper truss slice 402 one by one in sequence. Align the node plates 6 of the upper and lower arch rib trusses vertically. Use the method of hanging a plumb line to match the ground sample and review the alignment. Adjust the matching of the main chord pipe orifices 5 and temporarily lock them. After the upper truss slice 402 is positioned, install the connecting rods between the upper and lower trusses, and weld all the connecting welds as required to complete the assembly and manufacture of the single limb structure of the double-layer truss arch rib.

[0055] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for horizontally assembling the steel arch rib of a long-span arch bridge, which adopts a horizontally assembled falsework structure for the steel arch rib of a long-span arch bridge. The steel arch rib is composed of at least one truss panel. The overall cross-section of the steel arch rib is arc-shaped and bent. The truss panel nodes of each segment of the steel arch rib are located in the same vertical plane. Node plates are provided at the nodes. The node plates are arranged parallel to each other vertically. The falsework structure is composed of several falsework units connected in sequence. The falsework units gradually increase in height from one side to the other side. The falsework units are assembled vertically near each node plate. The falsework units are made of profiled steel materials. The falsework units are divided into at least one layer vertically. The number of layers of the falsework units matches the number of truss panels of a node of the steel arch rib. The falsework unit includes a bottom frame body and an upper frame body. The bottom frame body is fixedly connected to the concrete hardened ground of the assembly site. The upper frame body is a movable structure. The bottom frame body and the upper frame body are connected by bolts. It is characterized in that, The assembling method includes the following steps: Step S1) On the assembly site with a hardened ground, according to the elevation arch axis shape and structural dimensions of the steel arch rib, comprehensively considering the segment length and weight, reducing the self-weight deformation of the horizontal assembly, avoiding the node plates, weld areas and segment butt joints, determine the placement position of the falsework along the elevation curve of the steel arch rib on the hardened ground, and draw a ground line on the hardened ground; Step S2) According to the placement position of the falsework on the hardened ground, the plane arch axis shape and structural dimensions of the steel arch rib to be assembled, determine the manufacturing heights of the bottom frame body and the upper frame body; Step S3) According to the manufacturing height and stress state of the falsework, manufacture and complete the bottom frame body and the upper frame body according to the processing dimensions. According to the determined placement position and ground line, position and install the bottom frame body on the hardened ground of the assembly site, and connect it firmly to the hardened ground with expansion bolts; Step S4) Measure the elevation of the bottom frame body, adjust the overall line shape of the falsework by changing the size of the shim plate, measure and recheck the elevation and position coordinates of the frame body again to ensure that the line shape meets the accuracy requirements for the horizontal assembly of the steel arch rib; Step S5) Assemble the truss panels of the arch rib in single pieces. The bottom truss panels and the upper truss panels share the same set of ground lines for single-piece assembly. After all the truss panels of each layer are assembled in pieces, on the basis of retaining the bottom truss panels, install the movable upper frame body on the bottom frame body. The bottom frame body and the upper frame body are connected by connecting flanges; Step S6) After measuring and adjusting the line shape of the upper frame body and rechecking it to be qualified, hoist the upper truss panels sequentially. Align the node plates of the upper and lower arch rib trusses vertically, use a plumb line to match the ground line and recheck the line shape, adjust the matching of the main chord pipe orifices and temporarily lock them. After the upper truss panels are positioned, install the connecting members between the upper and lower trusses, and weld all the connecting welds as required to complete the assembly and manufacture of the double-layer truss arch rib single limb structure.

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