Construction method for climbing cone anchoring type bracket of pier cap of gate-type pier

Abstract

The invention relates to the technical field of bridge construction, in particular to a gate-type pier cap climbing cone anchoring type bracket construction method which mainly solves the technical problem that large potential safety hazards exist when a cast-in-place pier cap is operated through a floor stand. The construction method comprises the steps that S1, pier top steel bars are bound; s2, preassembling a climbing cone assembly; s3, mounting a pier top template; s4, positioning a climbing cone; s5, pier top concrete pouring; s6, an inner side formwork of the pier top is dismantled, and concrete curing is conducted; s7, mounting a bracket and establishing a bracket system; s8, mounting a pier cap template; s9, pier cap steel bars and concrete are constructed; and S10, the formwork and the support system are dismantled. According to the construction method, the pre-buried climbing cone assembly is connected with the bracket and is matched with the support system to serve as a bracket to support pier cap construction, a floor stand does not need to be installed, the installation and detachment efficiency is improved, the labor cost is reduced, and meanwhile potential safety hazards are reduced; in addition, the structure can be reused, and is more energy-saving and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a construction method of a portal pier cap climbing cone anchoring bracket. Background Art

[0002] In bridge construction, except for some pier caps across the line which will use prefabricated steel boxes, most of the portal pier caps are cast-in-place.

[0003] In the prior art, cast-in-place pier caps are generally constructed using floor-standing brackets, which have the advantages of simple process and safe force bearing. However, the disadvantages are that the installation and disassembly process of the floor-standing brackets is time-consuming and labor-intensive, and the operators need to stay at heights for a long time, which poses a great safety hazard. Summary of the invention

[0004] In order to overcome the technical defects of the prior art that the cast-in-place pier caps are time-consuming, labor-intensive and have great safety hazards when operated using floor-standing brackets, the present invention provides a construction method for a portal pier cap climbing cone anchoring bracket.

[0005] The construction method of the portal pier cap climbing cone anchoring bracket provided by the present invention comprises: S1. Pier top reinforcement binding; S2. Pre-install a climbing cone assembly, wherein the climbing cone assembly is formed by a plurality of climbing cone connectors fixedly connected through a well grid frame, each climbing cone connector is fixed to a cross node of the well grid frame, the climbing cone connector comprises an embedded plate, a high-strength screw and a climbing cone nut, the embedded plate and the climbing cone nut are respectively screwed to the two ends of the high-strength screw, and after pre-installation, the bolt opening of the climbing cone nut is sealed with tape; S3. Installation of pier top formwork; S4. A plurality of the climbing cone assemblies are placed on the piers on both sides of the portal pier in the transverse direction of the bridge, and the grid frame is welded and fixed to the steel bars on the top of the pier; S5. Concrete pouring on the pier top; S6. Remove the inner formwork of the pier top and perform concrete curing; S7. The bracket is fixed to the climbing cone assembly by a pad bolt, and a removal block is placed on the bracket, and then a transverse distribution beam is placed on the removal block, and finally a longitudinal distribution beam is placed on the transverse distribution beam, and the bracket system is built; S8. Installation of pier cap formwork; S9. Pier cap reinforcement and concrete construction; S10. Remove the formwork and support system.

[0006] Optionally, each set of climbing cone assemblies includes nine climbing cone connectors, and the nine climbing cone connectors are arranged in a square.

[0007] Optionally, each set of climbing cone assemblies is configured with two well grid frames, which are distributed along the axial direction of the high-strength screw and are fixedly connected to the embedded plate and the high-strength screw respectively.

[0008] Optionally, in step S10, the pier cap formwork is removed first, then the support system is removed, and finally the remaining formwork on the pier top is removed.

[0009] The technical solution provided by the present invention has the following advantages compared with the prior art: The construction method of the portal pier cap climbing cone anchoring bracket provided by the present invention connects the corbels through the pre-buried climbing cone components, and cooperates with the bracket system as a bracket to support the pier cap construction. There is no need to install a floor bracket, which improves the efficiency of installation and dismantling, reduces labor costs, and also reduces safety hazards. In addition, the structure can also be reused, which is more energy-saving and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0012] Figure 1 A flow chart showing a construction method according to an embodiment of the present invention; Figure 2 A schematic diagram of the assembly structure of a climbing cone assembly and a corbel in an embodiment of the present invention is shown.

[0013] In the figure: 1. Embedded plate; 2. High-strength screw; 3. Climbing cone nut; 4. Bolt with washer; 5. Corbel. DETAILED DESCRIPTION

[0014] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0015] It should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0016] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0017] Combine the following Figure 1 and Figure 2 The specific embodiments of the present invention are described in detail.

[0018] The present embodiment provides a construction method for a portal pier cap climbing cone anchoring bracket, comprising steps S1 to S10.

[0019] S1. Tie up the steel bars on the pier top.

[0020] It should be noted that the pier top reinforcement binding must be carried out in accordance with the design requirements, where the staggered positions of the main reinforcement joints and stirrup joints meet the requirements of the specifications, and the lap welding meets the requirements of the design and specifications; when binding the pier top reinforcement, the reinforcement at the corresponding position needs to be staggered according to the reinforcement spacing of the climbing cone.

[0021] S2. Pre-install the climbing cone assembly. The climbing cone assembly is composed of multiple climbing cone connectors fixedly connected through a manhole grid frame. Each climbing cone connector is fixed on a cross node of the manhole grid frame. The climbing cone connector includes an embedded plate 1, a high-strength screw rod 2 and a climbing cone nut 3. The embedded plate 1 and the climbing cone nut 3 are respectively screwed on the two ends of the high-strength screw rod 2. After pre-installation, the bolt mouth of the climbing cone nut 3 is sealed with tape.

[0022] Specifically, in this embodiment, each set of climbing cone assemblies includes nine climbing cone connectors, and the nine climbing cone connectors are arranged in a square.

[0023] Specifically, each set of climbing cone assembly is equipped with two well grid frames, which are distributed along the axial direction of the high-strength screw 2 and are respectively fixedly connected to the embedded plate 1 and the high-strength screw 2. By fixing with two well grid frames, the structure is more stable and not easy to shift.

[0024] It is easy to understand that the purpose of sealing the bolt opening of the climbing cone nut 3 with adhesive tape is to prevent the bolt hole from being blocked during subsequent concrete pouring.

[0025] S3. Installation of pier top formwork.

[0026] Specifically, the pier top formwork of this embodiment adopts a standardized steel formwork.

[0027] It should be noted that due to the large number of templates on site, the templates need to be carefully checked before installation to avoid mistakes. Before installing the template, the position of the embedded climbing cone needs to be marked on the template under the pier according to the design requirements. After the template is installed, the surveyors and technicians should measure and check it to ensure that the template installation position and verticality meet the requirements. When installing the template, the misalignment must be strictly controlled, and the joints should be affixed with double-sided tape to prevent leakage.

[0028] S4. Place multiple climbing cone assemblies on both sides of the pier body in the transverse direction of the portal pier, and weld the grid frame to the pier top steel bars.

[0029] Specifically, in this embodiment, two climbing cone assemblies are arranged on a single-side pier body, and in other embodiments, the number of climbing cone assemblies is determined after load inspection and calculation of the pier cap.

[0030] It is easy to understand that since the climbing cone is the most important load-bearing component in the entire support system, the accuracy of its installation position will directly affect the success or failure of the installation of the corbel 5. After the pier top formwork is installed, the climbing cone assembly is hoisted to the designated position on the pier top as a whole. The climbing cone assembly is tightly attached to the formwork according to the position of the design drawing, and the two layers of steel mesh are welded and fixed to the main reinforcement and stirrups on the pier top to prevent the embedded parts from being misplaced during the concrete pouring process, which affects the installation of the corbel 5.

[0031] S5. Pouring of concrete on pier top.

[0032] It should be noted that before pouring concrete, the installation of the protective layer and the formwork tie rods should be checked to ensure that the protective layer meets the design requirements and that the tie rod layout meets the design and is fixed. When pouring concrete, the vibrating rod is not allowed to touch the climbing cone assembly to ensure that the embedded position does not deviate. When using an inserted vibrator to vibrate, the moving spacing should not exceed 1.5 times the vibration action radius. The general action radius of the vibrating rod is 30cm to 40cm; a distance of 5cm to 10cm should be maintained from the side form; when vibrating the upper layer, it should be inserted into the lower layer of concrete by about 5cm to 10cm, and before the lower layer begins to set. The top surface of the poured concrete must be finished to prevent cracking on the top surface of the concrete and affect the quality of the concrete.

[0033] S6. Remove the inner formwork of the pier top and cure the concrete.

[0034] It should be noted that the pier top formwork is not completely removed. Only the formwork on the inner side of the portal pier leg is removed, and the formwork on the other three surfaces is still retained to ensure that the tie rods and diagonal tie rods are not loose, providing support for the subsequent upper pier cap formwork.

[0035] Specifically, the concrete curing of this embodiment adopts drip irrigation + geotextile for curing, and the curing time is 7 days. During the curing period, a dedicated person is appointed to ensure that the curing quality meets the design requirements.

[0036] S7. Fix the corbel 5 to the climbing cone assembly through the washer bolts 4, and place the unloading block on the corbel 5, then place the transverse distribution beam on the unloading block, and finally place the longitudinal distribution beam on the transverse distribution beam, and the support system is completed.

[0037] It is easy to understand that the climbing cone assembly, the unloading block, the transverse distribution beam and the longitudinal distribution beam together constitute the support system.

[0038] It should be noted that the load-bearing cross-section of the corbel 5 should be sufficient to accommodate the lower unloading block.

[0039] Specifically, when installing the corbel 5, first find the embedded position of the climbing cone assembly on the pier top, chisel off the concrete slurry on the surface, pierce the tape to make its surface flat; then use the high-strength washer bolts 4 equipped with the climbing cone assembly to bolt the corbel 5 to the pier body.

[0040] Specifically, the transverse distribution beam of this embodiment adopts double-pieced 40a I-beams, the length of which is shorter than the length of the arch to ensure the convenience of placement and removal; the specification of the longitudinal distribution beam is I32 I-beam.

[0041] S8. Installation of pier cap formwork.

[0042] Specifically, the pier cap formwork of this embodiment adopts a standardized steel formwork.

[0043] It should be noted that due to the complex shape and large number of templates, the positions of embedded parts such as channel openings need to be carefully checked before installation. Apply release agent after the template is polished. Apply the release agent evenly, use as little as possible, and only apply until it is shiny. Applying too much can easily cause bubbles and oil spots. After the template is installed, the surveyors and technicians should measure and check it to ensure that the template installation position and verticality meet the requirements. When installing the template, the misalignment must be strictly controlled, and double-sided tape should be affixed to the joints to prevent leakage.

[0044] S9. Pier cap reinforcement and concrete construction.

[0045] Specifically, the transverse length of the portal pier cap of this embodiment is greater than 10m, so the steel bars are processed in a steel bar processing plant and sent to the site for binding, and temporary supports are set up. Round pads are used for the side pads for steel bar binding, and attention is paid to the installation of the embedded reinforcement of the pad stone when binding the steel bar skeleton.

[0046] Specifically, the pier cap concrete of this embodiment is poured by a delivery pump according to design requirements. The pouring of concrete is based on the principle of horizontal layering and continuous pouring. After the initial setting of the concrete, curing begins, using a method of covering with geotextile + drip irrigation with fresh water.

[0047] S10. Remove the formwork and support system.

[0048] Specifically, in this embodiment, the pier cap formwork is first removed, then the support system is removed, and finally the remaining formwork on the pier top is removed to meet the principle of safety, convenience, and support before removal.

[0049] It should be noted that the removal of the pier cap formwork and support shall be carried out in accordance with the design requirements. When there is no design requirement, according to the "Code for Construction of Concrete Structures" (GB 50666-2011), when the member span is ≤8m, the bottom formwork and support can be removed when the arch specimens cured under the same conditions reach more than 75% of the design concrete strength grade.

[0050] It should be noted that the demolition work needs to be done layer by layer, and it is strictly forbidden to work at the same time; during the demolition process, all loosened components should be removed and transported in time to avoid accidental support or leaning; the removed rods should be lifted or transported out in a safe manner, and it is strictly forbidden to throw them down. After the climbing cone is removed, the demolition position needs to be repaired with cement mortar. The removal of the formwork and the bracket is carried out by two cranes at the same time, and they are arranged in the longitudinal direction of the bridge on both sides of the pier. During the demolition of the arch, special attention should be paid to the single-person command of the two cranes, and the hooks should be lowered at the same time to avoid imbalance and cause the crane to overturn.

[0051] The above is only a specific implementation of the present invention, which enables those skilled in the art to understand or implement the present invention. Although detailed descriptions are given with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; 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, and they should all be covered by the protection scope of the claims.

Claims

1. A construction method for a portal pier cap climbing cone anchor bracket, characterized in that: include: S1. Pier top reinforcement binding; S2. Pre-install a climbing cone assembly, wherein the climbing cone assembly is formed by a plurality of climbing cone connectors fixedly connected via a well grid frame, each climbing cone connector being fixed to a cross node of the well grid frame, the climbing cone connector comprising an embedded plate (1), a high-strength screw (2) and a climbing cone nut (3), the embedded plate (1) and the climbing cone nut (3) being respectively screwed to the two ends of the high-strength screw (2), and after pre-installation, the bolt opening of the climbing cone nut (3) is sealed with adhesive tape; S3. Installation of pier top formwork; S4. A plurality of the climbing cone assemblies are placed on the piers on both sides of the portal pier in the transverse direction of the bridge, and the grid frame is welded and fixed to the steel bars on the top of the pier; S5. Concrete pouring on the pier top; S6. Remove the inner formwork of the pier top and perform concrete curing; S7. The bracket (5) is fixed to the climbing cone assembly by a washer bolt (4), and a removal block is placed on the bracket (5), and then a transverse distribution beam is placed on the removal block, and finally a longitudinal distribution beam is placed on the transverse distribution beam, and the support system is completed; S8. Installation of pier cap formwork; S9. Pier cap reinforcement and concrete construction; S10. Remove the formwork and support system.

2. The construction method of the portal pier cap climbing cone anchor bracket according to claim 1 is characterized in that: Each set of climbing cone assemblies includes nine climbing cone connectors, and the nine climbing cone connectors are arranged in a square.

3. The construction method of the portal pier cap climbing cone anchor bracket according to claim 2 is characterized in that: Each set of climbing cone assemblies is equipped with two well grid frames, which are distributed along the axial direction of the high-strength screw rod (2) and are respectively fixedly connected to the embedded plate (1) and the high-strength screw rod (2).

4. The construction method of the portal pier cap climbing cone anchoring bracket according to any one of claims 1 to 3, characterized in that: In step S10, the pier cap formwork is first removed, then the support system is removed, and finally the remaining formwork on the pier top is removed.

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