A construction method for pre-tensioning and installing the horizontal steel-concrete combined section of a special-shaped landscape bridge

Abstract

The present application discloses a construction method for pre-tensioning and installation of a special-shaped landscape bridge horizontal steel-concrete joint section, which relates to the field of pre-tensioning of bridge horizontal steel-concrete joint sections and includes the following steps: S1. Hoisting of the steel box girder section in the steel-concrete joint section; S2. Construction of PBL shear keys in the steel box girder section of the steel-concrete joint section; S3. Installation of positioning tooling to restrict the displacement of the tensioning anchor and the cantilever end of the steel bar; S4. Passing the tensioning anchor and the steel bar through the rib plate of the steel box girder section and carrying out the anchoring construction of the tensioning anchor; S5. Pre-tensioning construction of the steel-concrete joint section; S6. Pouring construction of the concrete section of the steel-concrete joint section; S7. Tensioning construction of the steel-concrete joint section; The positioning tooling includes a clamping ring elastically clamped on the outside of the cantilever end of the tensioning anchor. The clamping ring is provided with a positioning member corresponding to the steel bar, and the positioning member is clamped and sleeved on the outer circumference of the steel bar. A limiting member is provided between two adjacent clamping rings. The present application has the effects of eliminating the need for manual docking by construction personnel, reducing the docking difficulty, and improving the docking efficiency.

Description

Technical Field

[0001] The present invention relates to the field of pre-tensioning of horizontal steel-concrete composite sections of bridges, and in particular to a pre-tensioning installation construction method for horizontal steel-concrete composite sections of special-shaped landscape bridges. Background Art

[0002] During the construction of a landscape bridge, the concrete abutments on both sides of the main beam are respectively located on the ground on both sides of the river. The main beam is divided into multiple steel box girder segments. Steel-concrete composite sections for connecting the abutments and the steel box girder segments are respectively divided at the abutments on both sides of the main beam, and a prestressing system is provided therein. The prestressing system adopts single-end tensioning, the fixed end is located inside the steel box girder segment, the tensioning end is located on the abutment side, and expansive concrete is used for filling.

[0003] As Figure 1 and Figure 2 shown, a strand passing hole 211 for passing the tensioning anchor and the steel bars is formed in the rib plate 21 in the steel box girder segment 2. Before the prestressing system is tensioned, the tensioning anchor in the prestressing system and the steel bars arranged on the periphery of the tensioning anchor need to be inserted into the strand passing hole 211 of the rib plate 21 of the steel box girder segment 2.

[0004] However, the number of tensioning anchors and steel bars arranged on the periphery of the tensioning anchor in the prestressing system is large, and due to the long length of its cantilever end extending out of the abutment, the cantilever end is prone to displacement to varying degrees. During the actual construction process, when the tensioning anchor and the steel bars around it are inserted into the rib plate in the steel box girder segment, manual docking by construction workers is required. However, the rib plate is located inside the steel box girder segment, resulting in high docking difficulty and low docking efficiency. Summary of the Invention

[0005] In order to reduce the docking difficulty between the tensioning anchor and the steel bars and the steel box girder segment, the present application provides a pre-tensioning installation construction method for horizontal steel-concrete composite sections of special-shaped landscape bridges.

[0006] A pre-tensioning installation construction method for horizontal steel-concrete composite sections of special-shaped landscape bridges provided by the present application adopts the following technical solutions:

[0007] A pre-tensioning installation construction method for horizontal steel-concrete composite sections of special-shaped landscape bridges includes the following steps:

[0008] S1. Hoisting the steel box girder segment in the steel-concrete composite section;

[0009] S2. Constructing the PBL shear keys in the steel box girder segment of the steel-concrete composite section;

[0010] S3. Installing the positioning tooling to limit the displacement of the cantilever ends of the tensioning anchor and the steel bars;

[0011] S4. Passing the tensioning anchor and the steel bars through the rib plate of the steel box girder segment and constructing the anchoring of the tensioning anchor;

[0012] S5. Pre-tensioning construction of the steel-concrete composite section;

[0013] S6. Concrete section pouring construction of the steel-concrete composite section;

[0014] S7. Tensioning construction of the steel-concrete composite section;

[0015] The positioning tooling includes a clamping ring elastically clamped on the outer side of the overhanging end of the tensioning anchor. The clamping ring is provided with positioning parts corresponding to the steel bars. The positioning parts are clamped and sleeved on the outer periphery of the steel bars. A limiting part is arranged between two adjacent clamping rings.

[0016] By adopting the above technical solutions, before threading the tensioning anchor and the steel bars, the clamping ring is connected to the outer side of the tensioning anchor to limit the displacement of the steel bars on the outer periphery of the tensioning anchor. Then the limiting part is connected between adjacent clamping rings to limit the displacement of adjacent tensioning anchors, realizing the limitation of the overhanging ends of the tensioning anchor and the steel bars. Moving the steel box girder segment can make the tensioning anchor and the steel bars penetrate into the rib plate of the steel box girder segment. Continuing to move the steel box girder segment makes the rib plate abut against the clamping ring. The clamping ring moves along the tensioning anchor under the action of external force, that is, the whole positioning tooling moves with the movement of the steel box girder segment until the steel box girder segment moves into place. By setting the positioning tooling and reasonably setting the construction steps, in the actual construction process, it is convenient to pass the tensioning anchor and the steel bars on its periphery through the rib plate in the steel box girder segment, without manual docking by construction workers, reducing the docking difficulty and improving the docking efficiency.

[0017] Preferably, the positioning part is arranged in an O shape.

[0018] By adopting the above technical solutions, the steel bars are threaded through the positioning parts, and the positioning parts play a supporting role for the steel bars to limit the displacement of the steel bars.

[0019] Preferably, the inner diameter of the positioning part gradually decreases from the tensioning end to the fixed end of the prestressing system.

[0020] By adopting the above technical solutions, the inner diameter of one end of the positioning part close to the tensioning end is larger, reducing the difficulty of inserting the steel bars into the positioning parts. The inner diameter of one end of the positioning part close to the fixed end is smaller, realizing the limitation of the steel bars.

[0021] Preferably, the tensioning anchor includes steel strands and a corrugated pipe sleeved on the outer side of the steel strands.

[0022] By adopting the above technical solutions, the steel strands are arranged inside the corrugated pipe, and pouring concrete will not affect the steel strands, so as to ensure the normal progress of the tensioning construction.

[0023] Preferably, a clamping groove is formed on the inner side of the clamping ring, and an elastic protrusion is arranged on the outer side of the corrugated pipe. The elastic protrusion is elastically fitted in the clamping groove.

[0024] By adopting the above technical solution, the connection between the clamping ring and the tensioning anchor is realized. When an external force acting along the axial direction of the tensioning anchor is applied to the clamping ring, the elastic protrusion disengages from the connection with the clamping groove, enabling the clamping ring to move along the tensioning anchor.

[0025] Preferably, the tensioning anchors are arranged in a rectangular array.

[0026] By adopting the above technical solution, a plurality of tensioning anchors jointly form a tensioning structure in a rectangular area, with high stability.

[0027] Preferably, a transverse limiting member is provided between any two horizontally adjacent clamping rings, and a longitudinal limiting member is provided between any two vertically adjacent clamping rings. The longitudinal limiting member has the same structure as the transverse limiting member.

[0028] By adopting the above technical solution, the transverse limiting member and the longitudinal limiting member limit the relative displacement between horizontally adjacent and vertically adjacent clamping rings, thereby limiting the displacement between horizontally adjacent and vertically adjacent tensioning anchors.

[0029] Preferably, the transverse limiting member includes a screw rod and a nut sleeve threadedly connected to the outside of the screw rod. The opposite ends of the screw rod and the nut sleeve are respectively connected to two clamping rings.

[0030] By adopting the above technical solution, it is convenient for construction personnel to adjust the screw rod and the nut sleeve according to the actual distance between two horizontally adjacent tensioning anchors at the construction site, increasing the adaptability of the transverse limiting member.

[0031] Preferably, a connecting ring is fixedly provided on the outside of the clamping ring. Hooks are respectively provided at the opposite ends of the screw rod and the nut sleeve, and the hooks are hung on the corresponding connecting rings.

[0032] By adopting the above technical solution, during connection, the hooks are hung on the connecting rings to realize the connection between the transverse limiting member and the clamping ring. The connecting components are simple and convenient for disassembly and assembly.

[0033] Preferably, in step S4, before threading the tensioning anchor and the steel bar, graphite powder is applied to the tendon passing holes of the rib plate;

[0034] In step S7, after the tensioning construction of the steel-concrete combined section is completed, the graphite powder in the tendon passing holes is blown out.

[0035] By adopting the above technical solution, the graphite powder plays a lubricating role in the tendon passing holes, which is beneficial to reducing the friction between the tensioning anchor or the steel bar and the rib plate when passing through the rib plate.

[0036] In summary, the present application includes at least one of the following beneficial technical effects:

[0037] 1. By setting up the positioning tooling and reasonably arranging the construction steps, during the actual construction process, it is convenient to pass the tensioning anchor and the steel bars on its periphery through the rib plate in the steel box girder segment, eliminating the need for manual docking by construction workers, reducing the docking difficulty, and improving the docking efficiency.

[0038] 2. The cooperation between the card slot and the elastic protrusion realizes the connection between the clamping ring and the tensioning anchor. When an external force acts on the clamping ring along the axial direction of the tensioning anchor, the elastic protrusion disengages from the card slot, enabling the clamping ring to move along the tensioning anchor. Description of the Drawings

[0039] Figure 1 It is a schematic structural diagram showing the abutment, steel box girder segment, tensioning anchor and steel bar structure in the background art.

[0040] Figure 2 It is a schematic structural diagram showing the steel box girder segment structure in the background art.

[0041] Figure 3 It is a schematic diagram showing the abutment, steel box girder segment, tensioning anchor, steel bar and positioning tooling structure in the background art.

[0042] Figure 4 Is Figure 3 The partial enlarged schematic diagram of part A in

[0043] Figure 5 It is a schematic side view showing the steel box girder segment structure in the embodiment.

[0044] Figure 6 It is a partial cross-sectional schematic diagram showing the connection structure between the clamping ring and the tensioning anchor in the embodiment.

[0045] Figure 7 It is a partial cross-sectional schematic diagram showing the connection structure between the positioning member and the steel bar in the embodiment.

[0046] Description of the Reference Numerals:

[0047] 1. Abutment; 2. Steel box girder segment; 21. Rib plate; 211. Strand passing hole; 3. Tensioning anchor; 31. Steel strand; 32. Bellows; 321. Elastic protrusion; 4. Steel bar; 5. Positioning tooling; 51. Clamping ring; 511. Card slot; 512. Connection ring; 52. Positioning member; 53. Screw rod; 54. Screw sleeve; 55. Hook. Detailed Description of the Embodiment

[0048] The following is a further detailed description of the present application in conjunction with the attached Figures 3 - 7 drawings.

[0049] The embodiment of the present application discloses a pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge, including the following steps:

[0050] S1. Hoisting of the steel box girder segments in the steel-concrete composite section:

[0051] Hoisting platforms are set on the ground on both sides of the river channel, and a 450t truck crane is used for hoisting each segment. Hoist the steel box girder segment 2 so that it is horizontally located on one side of the abutment 1, and there is a distance between the steel box girder segment 2 and the overhanging ends of the tensioning anchors 3 on the abutment 1 and the steel bars 4 arranged on the periphery of the tensioning anchors 3, so as to facilitate the subsequent construction of the construction personnel.

[0052] Among them, the tensioning anchors 3 are arranged in a rectangular array. The tensioning anchor 3 includes steel strands 31 and corrugated pipes 32 sleeved outside the steel strands 31. The corrugated pipes 32 are used to isolate the steel strands 31, and the pouring of concrete at the abutment 1 will not affect the steel strands 31, ensuring the normal progress of the tensioning work.

[0053] In this embodiment, four steel bars 4 are evenly distributed on the periphery of the tensioning anchor 3.

[0054] S2. Construction of PBL shear keys in the steel box girder segments in the steel-concrete composite section:

[0055] Construct PBL shear keys in the steel box girder segment 2. The PBL shear keys use steel bars 4 with a diameter of 25mm, and are arranged in two upper and lower layers, and are arranged in a staggered manner with the tensioning anchors 3 and the steel bars 4. The PBL shear keys are not shown in the drawings.

[0056] S3. Installation of positioning tooling:

[0057] Install positioning tooling 5 for restricting the displacement of the tensioning anchors 3 and the steel bars 4 at the overhanging ends of the tensioning anchors 3 and the steel bars 4. The positioning tooling 5 includes a clamping ring 51, a positioning member 52, a lateral limiting member and a longitudinal limiting member. The structure of the longitudinal limiting member is the same as that of the lateral limiting member.

[0058] The clamping rings 51 correspond to the tensioning anchors 3 one by one. A clamping groove 511 is opened on the inner side of the clamping ring 51. A plurality of clamping grooves 511 are evenly distributed along the circumferential direction of the clamping ring 51. Elastic protrusions 321 corresponding to the clamping grooves 511 are fixed on the outer side of the overhanging end of the corrugated pipe 32, and the elastic protrusions 321 are elastically fitted into the clamping grooves 511; positioning members 52 corresponding to the steel bars 4 one by one are fixed on the outer wall of the clamping ring 51. The positioning members 52 are arranged in an O shape. To facilitate the penetration of the steel bars 4 into the positioning members 52, the inner diameter of the positioning members 52 gradually decreases from the tensioning end to the fixed end of the prestressing system.

[0059] The lateral limiting members are arranged between two laterally adjacent clamping rings 51, and the longitudinal limiting members are arranged between two longitudinally adjacent clamping rings 51.

[0060] The lateral limiting member includes a screw rod 53 and a nut sleeve 54 threadedly connected to the outside of the screw rod 53. Hooks 55 are respectively fixed to the two ends of the screw rod 53 and the nut sleeve 54 facing away from each other. A connecting ring 512 corresponding to the hook 55 is fixed on the clamping ring 51, and the hook 55 is used for hanging and connecting with the connecting ring 512.

[0061] When installing and positioning the tooling 5, first sleeved the clamping ring 51 on the outside of the cantilever end of the tension anchor 3, move the clamping ring 51 towards the tension end of the prestressed system, so that the elastic protrusion 321 is embedded in the card slot 511, insert the steel bar 4 into the positioning member 52 to limit the relative displacement between the steel bar 4 and the tension anchor 3; then adjust the relative positions of the screw rod 53 and the nut sleeve 54, after adjusting to the appropriate position, hang the hook 55 on the connecting ring 512 to limit the displacement between the laterally adjacent and longitudinally adjacent tension anchors 3, realizing the positioning of the cantilever ends of the tension anchor 3 and the steel bar 4, so that the tension anchor 3 and the steel bar 4 can be smoothly inserted into the rib plate 21 of the steel box girder segment 2.

[0062] S4. Passing through the tension anchor and the steel bar:

[0063] Apply graphite powder on the inner wall of the cable duct 211 of the rib plate 21 of the steel box girder segment 2. Lift and move the steel box girder segment 2 by a truck crane, so that the steel box girder segment 2 continuously approaches the abutment 1. During the movement of the steel box girder segment 2, apply a force to the clamping ring 51 to separate the elastic protrusion 321 from the connection with the card slot 511, that is, the whole positioning tooling 5 moves with the movement of the steel box girder segment. During the movement of the steel box girder segment 2, the tension anchor 3 and the steel bar 4 are passed through the rib plate 21 of the steel box girder segment 2; after passing through, carry out the anchoring construction of the tension anchor 3 on the side of the steel box girder segment 2 away from the abutment 1.

[0064] S5. Pre-tensioning construction of the steel-concrete combined section:

[0065] Carry out the pre-tensioning construction of some tension anchors 3 in the steel-concrete combined section on the side of the abutment 1. In this embodiment, four tension anchors 3 arranged in a rectangular array in the middle are selected for pre-tensioning construction.

[0066] S6. Pouring construction of the concrete section of the steel-concrete combined section.

[0067] S7. Carry out the tensioning construction of the steel-concrete combined section on the side of the abutment 1. After the tensioning is completed, blow off the graphite powder in the cable duct 211.

[0068] In the pre-tensioning installation construction method of the special-shaped landscape bridge horizontal steel-concrete combined section in this embodiment, by setting the positioning tooling 5, it is convenient to pass the tension anchor 3 and the steel bar 4 on its periphery through the rib plate 21 inside the steel box girder segment 2 during the actual construction process, without the need for construction workers to manually dock one by one at the construction site, reducing the docking difficulty and improving the docking efficiency, which plays a good reference role for subsequent similar projects.

[0069] The above are all preferred embodiments of the present application, and do not limit the protection scope of the present application accordingly. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge, characterized in that, It includes the following steps: S1. Hoisting the steel box girder segment (2) in the steel-concrete composite section; Hoist the steel box girder segment (2) to be horizontally located on one side of the abutment (1), and there is a distance between the steel box girder segment (2) and the overhanging ends of the tension anchors (3) on the abutment (1) and the steel bars (4) arranged on the periphery of the tension anchors (3); The tension anchors (3) are arranged in a rectangular array, and the steel bars (4) are evenly distributed on the periphery of the tension anchors (3); S2. Construction of PBL shear keys in the steel box girder segment (2) of the steel-concrete composite section; Construct PBL shear keys in the steel box girder segment (2). The PBL shear keys adopt steel bars (4) with a diameter of 25 mm, are arranged in upper and lower double layers, and are arranged in a staggered manner with the tension anchors (3) and the steel bars (4); S3. Install the positioning tooling (5) to limit the displacement of the overhanging ends of the tension anchors (3) and the steel bars (4); S4. The tension anchors (3) and the steel bars (4) penetrate through the rib plate (21) of the steel box girder segment (2), and the tension anchors (3) are anchored for construction; S5. Pre-tensioning construction of the steel-concrete composite section; S6. Concrete section pouring construction of the steel-concrete composite section; S7. Tensioning construction of the steel-concrete composite section; The positioning tooling (5) includes a clamping ring (51) elastically clamped on the outer side of the overhanging end of the tension anchor (3). The clamping ring (51) is provided with positioning members (52) corresponding to the steel bars (4). The positioning members (52) are clamped and sleeved on the outer periphery of the steel bars (4). A limiting member is arranged between two adjacent clamping rings (51).

2. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 1, characterized in that: The positioning member (52) is arranged in an O shape.

3. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 2, characterized in that: The inner diameter of the positioning member (52) gradually decreases from the tensioning end to the fixed end of the prestressing system.

4. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 1, characterized in that: The tension anchor (3) includes steel strands (31) and a corrugated pipe (32) sleeved on the outer side of the steel strands (31).

5. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 4, characterized in that: A clamping groove (511) is formed on the inner side of the clamping ring (51). Elastic protrusions (321) are arranged on the outer side of the corrugated pipe (32), and the elastic protrusions (321) are elastically fitted into the clamping groove (511).

6. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 1, characterized in that: A transverse limiting member is arranged between any two horizontally adjacent clamping rings (51), and a longitudinal limiting member is arranged between any two longitudinally adjacent clamping rings (51). The longitudinal limiting member has the same structure as the transverse limiting member.

7. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 6, characterized in that: The transverse limiting member includes a screw rod (53) and a nut sleeve (54) threadedly connected to the outer side of the screw rod (53). The opposite ends of the screw rod (53) and the nut sleeve (54) are respectively connected to two clamping rings (51).

8. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 7, characterized in that: A connecting ring (512) is fixedly arranged on the outer side of the clamping ring (51). Hooks (55) are respectively arranged at the opposite ends of the screw rod (53) and the nut sleeve (54), and the hooks (55) are hung on the corresponding connecting rings (512).

9. The pre-tensioning installation construction method for the horizontal steel-concrete combined section of a special-shaped landscape bridge according to claim 1, characterized in that: In step S4, before the tension anchors (3) and the steel bars (4) penetrate through, graphite powder is coated on the cable duct (211) of the rib plate (21); In step S7, after the tensioning construction of the steel-concrete composite section is completed, the graphite powder in the cable duct (211) is blown out.

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