Symmetrical cantilever casting construction method adopting hanging baskets adjacent to business line

Abstract

The invention discloses a symmetric cantilever casting construction method adopting hanging baskets adjacent to a business line, and belongs to the technical field of bridge construction. The method comprises the following steps: S1, construction of lower structures of main piers and side piers of a continuous beam; s2, the 0 # section of the pier top is constructed through a support method; s3, the standard sections of the continuous beams are subjected to pouring construction through rhombic hanging basket cantilevers; s4, side span cast-in-place section closure is constructed through a bailey beam support method; and S5, the mid-span closure section box girder is constructed through a hanging bracket method. According to the construction method provided by the invention, quick and efficient hanging basket cantilever casting can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge construction, and in particular relates to a symmetrical cantilever casting construction method using a hanging basket adjacent to an operating line. Background Art

[0002] Construction adjacent to operating lines refers to non-explosive construction such as new railway projects, existing line reconstruction projects and local projects within the railway line safety protection zone (subject to the scope specified in the "Railway Transport Safety Protection Regulations"), as well as controlled blasting within 200 meters of the railway line center that affects or may affect the stability, use and driving safety of railway operating line equipment.

[0003] The hanging basket is the main equipment in cantilever construction. According to the structural form, it can be divided into four types: truss type, cable-stayed type, steel type and mixed type. According to the requirements of concrete cantilever construction process and the requirements of the design drawings for the hanging basket, the characteristics, weight, steel type, construction process, etc. of various types of hanging baskets are comprehensively compared; the design principles of the hanging basket are: light weight, simple structure, firm and stable, easy to move forward and assemble and disassemble, strong reusability, small deformation after being stressed, etc., and there is sufficient space under the hanging basket, which can provide a larger construction working surface, which is conducive to the construction operation of the steel formwork.

[0004] However, the existing hanging basket cantilever casting solutions generally have problems such as complicated procedures and low efficiency. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a symmetrical cantilever casting construction method using a hanging basket adjacent to an operating line, which adopts the following technical solutions:

[0006] A construction method using a hanging basket for symmetrical cantilever casting adjacent to an operating line comprises the following steps:

[0007] S1. Construction of the substructure of the main pier and side pier of the continuous beam;

[0008] S2, 0# section of pier top is constructed by bracket method;

[0009] S3, the standard section of the continuous beam is constructed by cantilever casting with a diamond hanging basket;

[0010] S4: The closure of the cast-in-place section of the side span is constructed using the Bailey beam support method;

[0011] S5. The box girder of the middle span joint section is constructed using the hanger method.

[0012] Furthermore, in step S1, the lower structure of the main pier of the continuous beam adopts parallel operation of the flowing working surface, and the upper structure of the main pier of the continuous beam is provided with two flowing working surfaces for each continuous beam, and each main pier is equipped with two hanging baskets for symmetrical construction, wherein one T-joint + side span cast-in-place section is one flowing working surface, and each flowing working surface operates in parallel.

[0013] Furthermore, in step S2, the steps of constructing the pier top 0# section using the bracket method are as follows:

[0014] S21. Set up the 0# segment formwork of the box girder on the bracket beside the main pier, tie the steel bars, and install the prestressed pipes;

[0015] S22, pouring concrete of box girder 0# segment;

[0016] S23. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars;

[0017] S24. Install the cantilever construction basket.

[0018] Furthermore, in step S24, the cantilever construction hanging basket is installed as a cyclic construction process, and the construction process is divided into:

[0019] S241, install track beams and tracks;

[0020] S242, install the track pressure beam and front support point;

[0021] S243, install the main truss system;

[0022] S244, install the shoulder beam, rear lower beam, suspension rod, and front upper beam;

[0023] S245, install the bottom basket longitudinal beam, outer mold, and sliding beam;

[0024] S246, install the bottom basket system.

[0025] Further, in step S3, the steps of cantilever casting and construction of the standard segment of the continuous beam using a diamond hanging basket are as follows:

[0026] S31. Carry out the construction of the 1# section of the box girder on the construction hanging basket, erect the formwork, tie the steel bars, and install the prestressed pipes;

[0027] S32, pouring concrete of box girder 1# segment;

[0028] S33. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars;

[0029] S34, move the construction hanging basket, and cast the 2#~N# segments in sequence according to the above steps;

[0030] S35, dismantle the construction hanging basket, install the bracket beside the side pier, and preload the bracket;

[0031] S36. Carry out cast-in-place construction of side span box beam segments on the support, erect formwork, tie steel bars, and install prestressed pipes;

[0032] S37. Pour cast-in-place segmental concrete of box girder.

[0033] Further, in step S4, the side span cast-in-place section closure is constructed by using the Bailey beam support method:

[0034] S41. Carry out the construction of the box girder side span closure section on the support, install the rigid frame, erect the formwork, tie the steel bars, and install the prestressed steel strands or steel bars;

[0035] S42, pouring concrete of the joint section of the side span box girder;

[0036] S43. After the concrete strength reaches 90% of the design strength, the temporary restraint of the side piers is released, and the prestressed steel strands or steel bars of the side spans are symmetrically tensioned and connected;

[0037] S44. Remove the support and allow the bearing to bear the force.

[0038] Further, in step S5, the middle span closure section box girder is constructed using the hanger method:

[0039] S51. Construct the middle span closure section on the hanger, install the rigid frame, erect the formwork, tie the steel bars, install the prestressed pipes, and pour the concrete;

[0040] S52. After the concrete strength reaches 90% of the design strength, the longitudinal tendons are symmetrically tensioned in the middle of the span;

[0041] S53, dismantle the entire bridge construction load;

[0042] S54. Carry out construction of bridge deck system and ancillary facilities.

[0043] Beneficial effects:

[0044] The pouring construction method of the present invention has higher operational safety, simple and quick construction steps, and can realize safe and efficient pouring construction of the bridge cantilever. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a main construction process flow chart of the symmetrical cantilever casting construction method using a hanging basket adjacent to the operating line of the present invention;

[0046] Figure 2 It is a cantilever construction hanging basket installation flow chart of the cantilever construction hanging basket symmetrical cantilever casting construction method of the present invention adjacent to the operating line;

[0047] Figure 3 It is a construction process flow chart of S1 and S2 of the construction method of symmetrical cantilever casting with hanging basket adjacent to the operating line of the present invention;

[0048] Figure 4 It is a construction process flow chart of S3 of the present invention using a hanging basket symmetrical cantilever casting construction method adjacent to the operating line;

[0049] Figure 5 It is a construction process flow chart of S4 of the present invention using a hanging basket symmetrical cantilever casting construction method adjacent to the operating line;

[0050] Figure 6 The present invention is a construction process flow chart of S6 of the symmetrical cantilever casting construction method using a hanging basket adjacent to the operating line. DETAILED DESCRIPTION

[0051] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below.

[0052] Example 1

[0053] Reference Figure 1-6 A symmetrical cantilever casting construction method using a hanging basket adjacent to an operating line comprises the following steps:

[0054] S1. Construction of the substructure of the main pier and side pier of the continuous beam;

[0055] S2, 0# section of pier top is constructed by bracket method;

[0056] S3. The standard section of the continuous beam is cast by a diamond hanging basket cantilever. The steps for casting the standard section of the continuous beam by a diamond hanging basket cantilever are as follows:

[0057] S31. Carry out the construction of the 1# section of the box girder on the construction hanging basket, erect the formwork, tie the steel bars, and install the prestressed pipes;

[0058] S32, pouring concrete of box girder 1# segment;

[0059] S33. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars;

[0060] S34, move the construction hanging basket, and cast the 2#~N# segments in sequence according to the above steps;

[0061] S35, dismantle the construction hanging basket, install the bracket beside the side pier, and preload the bracket;

[0062] S36. Carry out cast-in-place construction of side span box beam segments on the support, erect formwork, tie steel bars, and install prestressed pipes;

[0063] S37. Pour cast-in-place segmental concrete of box girder.

[0064] S4. The side span cast-in-place section is constructed by Bailey beam support method. The steps of the side span cast-in-place section closure by Bailey beam support method are as follows:

[0065] S41. Carry out the construction of the box girder side span closure section on the support, install the rigid frame, erect the formwork, tie the steel bars, and install the prestressed steel strands or steel bars;

[0066] S42, pouring concrete of the joint section of the side span box girder;

[0067] S43. After the concrete strength reaches 90% of the design strength, the temporary restraint of the side piers is released, and the prestressed steel strands or steel bars of the side spans are symmetrically tensioned and connected;

[0068] S44. Remove the support and allow the bearing to bear the force.

[0069] S5. The box girder of the middle span joint section adopts the hanger method for construction. The steps of the box girder of the middle span joint section adopts the hanger method for construction:

[0070] S51. Construct the middle span closure section on the hanger, install the rigid frame, erect the formwork, tie the steel bars, install the prestressed pipes, and pour the concrete;

[0071] S52. After the concrete strength reaches 90% of the design strength, the longitudinal tendons are symmetrically tensioned in the middle of the span;

[0072] S53, dismantle the entire bridge construction load;

[0073] S54. Carry out construction of bridge deck system and ancillary facilities.

[0074] In this embodiment, in step S1, the lower structure of the main pier of the continuous beam adopts parallel operation of the flowing working surface, and the upper structure of the main pier of the continuous beam is provided with two flowing working surfaces for each continuous beam, and each main pier is equipped with two hanging baskets for symmetrical construction, wherein one T-joint + side span cast-in-place section is one flowing working surface, and each flowing working surface operates in parallel.

[0075] Through the above technical solution, the specific implementation step S1 is as follows:

[0076] S11. Complete the construction of pier foundation and pier body;

[0077] S12. Install the bracket beside the main pier. If the main pier is higher, use a cantilever bracket.

[0078] In this embodiment, in step S2, the steps of constructing the pier top 0# section using the bracket method are as follows:

[0079] S21. Set up the 0# segment formwork of the box girder on the bracket beside the main pier, tie the steel bars, and install the prestressed pipes;

[0080] S22, pouring concrete of box girder 0# segment;

[0081] S23. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars;

[0082] S24, installing the cantilever construction hanging basket, wherein the installation of the cantilever construction hanging basket is a cyclic construction process, and the construction process is divided into:

[0083] S241, install track beams and tracks;

[0084] S242, install the track pressure beam and front support point;

[0085] S243, install the main truss system;

[0086] S244, install the shoulder beam, rear lower beam, suspension rod, and front upper beam;

[0087] S245, install the bottom basket longitudinal beam, outer mold, and sliding beam;

[0088] S246, install the bottom basket system.

[0089] Through the above technical solution, the safety assurance measures for the construction of the hanging basket cast-in-place continuous beam adjacent to the operating line are as follows:

[0090] ⑴ Except for the traction power supply professionals who work according to regulations, any personnel and the objects and tools they carry must keep a distance of more than 2m from the high-voltage live parts of the traction power supply equipment; keep a distance of more than 1m from the return line, overhead ground wire, and protection line. If the distance is insufficient, the traction power supply equipment must be powered off, and safety protection measures such as installing ground wires (referring to testing electricity and hanging ground wires in all possible directions of incoming power, the same below) must be taken;

[0091] (2) The working area must be kept at least 2m away from the high-voltage live parts of the traction power supply equipment, and at least 1m away from the return line, overhead ground wire, and protection line. If the distance is insufficient, the traction power supply equipment must be powered off, and safety protection measures such as installing ground wires must be taken;

[0092] ⑶ Before operating or handling emergency situations on facilities and equipment such as buildings or structures that are less than 2m away from the high-voltage live parts of the traction power supply equipment and less than 1m away from the return line, overhead ground wire, and protective wire, or after the traction power supply equipment is powered off, safety protection measures such as power outage and installation of ground wires must be taken before operating;

[0093] (4) During water supply, cleaning, construction and maintenance operations in the electrified section, water pipes must not be sprayed or water columns splashed in the direction of the power supply lines;

[0094] ⑸ When the traction power supply equipment fails, high voltage may occur in the pillars, grounding down conductors, integrated grounding wires, etc. connected to the traction power supply equipment. Before taking safety protection measures such as power outage and installation of grounding wires, non-professionals are prohibited from contacting them and keep a safe distance;

[0095] ⑹ It is strictly forbidden to throw ropes or other objects onto the contact network. If the traction power supply equipment is found to be broken or its components are damaged, or if there are foreign objects such as wire ends, ropes, plastic sheets, kites, branches, or detached overlaps hanging on the traction power supply equipment, no contact is allowed; before the traction power supply equipment maintenance personnel arrive and take measures, any personnel should stay 10m away from the broken wire or foreign objects;

[0096] ⑺Within 5m of the traction power supply equipment support and the live parts of the traction power supply equipment, metal structures with access to comprehensive grounding conditions should be included in the comprehensive grounding system;

[0097] ⑻ It is prohibited to erect scaffolding with the help of contact network pillars. When it is necessary to use contact network pillars to climb to a height, there must be power supply professionals on site to supervise.

[0098] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A symmetrical cantilever casting construction method using a hanging basket adjacent to an operating line, characterized in that: The steps include: S1. Construction of the substructure of the main pier and side pier of the continuous beam; S2, 0# section of pier top is constructed by bracket method; S3, the standard section of the continuous beam is constructed by cantilever casting with a diamond hanging basket; S4: The closure of the cast-in-place section of the side span is constructed using the Bailey beam support method; S5. The box girder of the middle span joint section is constructed using the hanger method.

2. The method for symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 1 is characterized in that: In step S1, the lower structure of the main pier of the continuous beam adopts parallel operation with a flowing working surface, and the upper structure of the main pier of the continuous beam is provided with two flowing working surfaces for each continuous beam, and each main pier is equipped with two hanging baskets for symmetrical construction, wherein one T-joint + side span cast-in-place section is one flowing working surface, and each flowing working surface operates in parallel.

3. The method for symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 1 is characterized in that: In step S2, the steps of constructing the pier top 0# section using the support method are as follows: S21. Set up the 0# segment formwork of the box girder on the bracket beside the main pier, tie the steel bars, and install the prestressed pipes; S22, pouring concrete of box girder 0# segment; S23. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars; S24. Install the cantilever construction basket.

4. The method for symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 3 is characterized in that: In step S24, the cantilever construction hanging basket is installed as a cyclic construction process, and the construction process is divided into: S241, install track beams and tracks; S242, install the track pressure beam and front support point; S243, install the main truss system; S244, install the shoulder beam, rear lower beam, suspension rod, and front upper beam; S245, install the bottom basket longitudinal beam, outer mold, and sliding beam; S246, install the bottom basket system.

5. The method of symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 1 is characterized in that: In step S3, the steps of cantilever casting of the standard section of the continuous beam using a diamond hanging basket are as follows: S31. Carry out the construction of the 1# section of the box girder on the construction hanging basket, erect the formwork, tie the steel bars, and install the prestressed pipes; S32, pouring concrete of box girder 1# segment; S33. After the concrete strength reaches 90% of the design strength, symmetrically tension the longitudinal, transverse and vertical prestressed steel strands or steel bars; S34, move the construction hanging basket, and cast the 2#~N# segments in sequence according to the above steps; S35, dismantle the construction hanging basket, install the bracket beside the side pier, and preload the bracket; S36. Carry out cast-in-place construction of side span box beam segments on the support, erect formwork, tie steel bars, and install prestressed pipes; S37. Pour cast-in-place segmental concrete of box girder.

6. The method of symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 1 is characterized in that: In step S4, the side span cast-in-place section is constructed by using the Bailey beam support method: S41. Carry out the construction of the box girder side span closure section on the support, install the rigid frame, erect the formwork, tie the steel bars, and install the prestressed steel strands or steel bars; S42, pouring concrete of the joint section of the side span box girder; S43. After the concrete strength reaches 90% of the design strength, the temporary restraint of the side piers is released, and the prestressed steel strands or steel bars of the side spans are symmetrically tensioned and connected; S44. Remove the support and allow the bearing to bear the force.

7. The method of symmetrical cantilever casting using a hanging basket adjacent to an operating line according to claim 1 is characterized in that: In step S5, the steps of constructing the box girder of the middle span closure section by using the hanger method are as follows: S51. Construct the middle span closure section on the hanger, install the rigid frame, erect the formwork, tie the steel bars, install the prestressed pipes, and pour the concrete; S52. After the concrete strength reaches 90% of the design strength, the longitudinal tendons are symmetrically tensioned in the middle of the span; S53, dismantle the entire bridge construction load; S54. Carry out construction of bridge deck system and ancillary facilities.

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