Construction method of cable-stayed bridge cable tower active cross brace serving as steel anchor box installation closure support

Abstract

The invention provides a construction method for installing a closure support by using a cable-stayed bridge cable tower active cross brace as a steel anchor box, which comprises the following steps of: pre-embedding a climbing cone when a concrete section before closure is poured, then installing an operation platform and the active cross brace, applying a cross brace jack on the operation platform, installing a distribution beam and a framed bent structure on the active cross brace, and installing a steel anchor box on the active cross brace. And the first section of the steel anchor box is hoisted, the concrete part of the cable bent tower closure section is poured, and cable bent tower closure and follow-up construction are completed. The construction method is simple in process, the structure is safe and reliable, the active cross braces serve as the steel anchor box closure support, temporary structural materials are saved, the number of tower body embedded parts is reduced, and economic benefits are good. According to the method, the problems of precise alignment and closure of high-altitude installation of the steel anchor box are solved, the line shape of a cable bent tower after closure is ensured, the structural stress safety after a bridge is formed is ensured, the construction efficiency and the construction quality are greatly improved, and the method has high popularization value.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge engineering, and in particular relates to a construction method for a closure bracket for installing an active cross brace of a cable-stayed bridge tower and serving as a steel anchor box. Background Art

[0002] The upper tower column of the cable-stayed bridge tower adopts a steel-concrete hybrid structure, and the anchorage area of ​​the cable at the tower end is an external steel anchor box. The main function of the steel anchor box is to anchor the cable, transfer the cable force to the tower, and offset the horizontal force of the cable to ensure the safety and stability of the bridge structure. Therefore, the installation accuracy of the steel anchor box is extremely high, and the installation error is controlled at the millimeter level. As a component of the cable tower joint section, the first section of the steel anchor box has a large hoisting weight and many construction safety risks. Compared with the traditional active cross bracing construction method, it is impossible to meet the installation accuracy of the steel anchor box, and a separate first section of the steel anchor box installation bracket or floor bracket is required. Therefore, it is difficult to hoist the steel anchor box at high altitude and ensure its installation accuracy and the linear shape of the cable tower after jointing, which requires further research in combination with design and construction. Summary of the invention

[0003] In view of this, the present invention aims to propose a construction method for a cable-stayed bridge tower active cross brace also serving as a steel anchor box installation closure bracket to solve the above-mentioned problem.

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

[0005] A construction method for installing a closure bracket for an active cross brace of a cable-stayed bridge tower and also serving as a steel anchor box, the method comprising the following steps:

[0006] S1. The lower tower column of the cable tower is constructed with traditional cross bracing;

[0007] S2. When pouring concrete of the section before the closure of the cable tower, embed the climbing cone in advance;

[0008] S3. After the concrete pouring is completed and reaches the designed strength, install the operating platform and active cross brace;

[0009] S4. Adjust the spacing between the closures by applying the jacking force of the horizontal support jack on the operating platform;

[0010] S5. Install the distribution beam and bent structure on the active cross brace;

[0011] S6. Observe the influence of temperature on the spacing of the joints. When the temperature is relatively stable at night, hoist the first section of the steel anchor box, install it in place and make fine adjustments.

[0012] S7. Pour concrete at the cable tower closure section to complete the cable tower closure and subsequent construction.

[0013] Further, in step S1, a climbing cone is embedded in the conventional cross brace when pouring the cable tower concrete, and a corbel is set. One end of the steel pipe cross brace is laid on the corbel and fastened to the tower body pad, and the other end is laid on the corbel and fastened to the tower body pad through a jack. The jacking force is applied by the jack to ensure that the tensile stress and linear shape of the tower column during the construction process meet the requirements of the specifications.

[0014] Further, in step S3, the active cross brace is made of section steel, one end of the section steel cross brace is placed on the corbel and fastened to the tower body pad, and the other end is placed on the corbel and fastened to the tower body pad through a jack.

[0015] Furthermore, in step S3, a jack pad is provided between the jack and the cable tower concrete segment, and a cross brace limiter is provided on the active cross brace.

[0016] Furthermore, in step S5, the distribution beams and the bent structures are arranged symmetrically about the center line of the tower.

[0017] Compared with the prior art, the construction method of the active cross brace of the cable-stayed bridge tower used as a joint support for the steel anchor box installation of the present invention has the following advantages:

[0018] The construction method of the active cross brace of the cable-stayed bridge tower also serving as the joint support for the installation of the steel anchor box described in the present invention has simple construction procedures and high construction efficiency. The active cross brace also serving as the joint support for the installation of the steel anchor box saves temporary structural materials, reduces the number of embedded parts of the tower body, and has good economic benefits. The active cross brace is closer to the joint mouth position and can more effectively adjust the joint mouth spacing, especially in high towers. The structure is safe and reliable with low safety risks. The active cross brace adjusts the joint mouth spacing by a jack before the steel anchor box is installed, which not only ensures the installation accuracy of the steel anchor box, but also ensures the joint line shape of the cable tower and the force safety of the structure after the bridge is completed; at the same time, the active cross brace rods and the frame structure provide a support platform for the installation of the steel anchor box and the joint of the cable tower, which greatly improves the construction efficiency and construction quality, and has great promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 This is a structural diagram of the cable tower closure section of a cable-stayed bridge;

[0021] Figure 2 This is a schematic diagram of the installation elevation of the active cross brace that also serves as a steel anchor box bracket;

[0022] Figure 3 This is a side view of the installation of the active cross brace that also serves as a steel anchor box bracket;

[0023] Figure 4This is a schematic diagram of the installation plan of the active cross brace;

[0024] Figure 5 This is a detailed diagram of the corbel position.

[0025] Description of reference numerals:

[0026] 1. Cable tower concrete segment; 2. Cable tower steel anchor box segment; 3. Concrete segment segment section line; 4. Steel anchor box segment segment section line; 5. Corbel; 6. Climbing cone; 7. Active cross brace; 8. Operating platform; 9. Distribution beam; 10. Frame structure; 11. Cross brace jack; 12. Jack pad; 13. Cross brace limiter. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0029] In the description of the present invention, 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 it can be indirectly connected 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 in the present invention can be understood by specific circumstances.

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1-5 As shown, a construction method for installing a joint support for an active cross brace of a cable-stayed bridge tower and serving as a steel anchor box includes the following steps:

[0032] S1. The lower tower column of the cable tower is constructed with traditional cross bracing;

[0033] The traditional cross brace is a pre-embedded climbing cone and a corbel when pouring the cable tower concrete. One end of the steel pipe cross brace is placed on the corbel 5 and fastened to the tower body pad, and the other end is placed on the corbel and fastened to the tower body pad through the jack 11. The jacking force is applied by the jack 11 to ensure that the tensile stress and linear shape of the tower column meet the requirements of the specifications during the construction process.

[0034] S2. When pouring concrete of the section before the cable tower closure section, embed the climbing cone 6.

[0035] S3, after the concrete pouring is completed and reaches the design strength, the operating platform 8 and the active cross brace 7 are installed;

[0036] The active cross brace is made of steel. One end of the steel cross brace is placed on the corbel and fastened to the tower body pad, while the other end is placed on the corbel and fastened to the tower body pad through a jack.

[0037] A jack pad 12 is provided between the jack and the cable tower concrete segment, and a cross brace limiting member 13 is provided on the active cross brace.

[0038] S4. On the operating platform, the spacing between the joints is adjusted by applying a jacking force from the cross bracing jack 11.

[0039] S5. Install distribution beams and frame structures on the active cross braces; the distribution beams and frame structures are arranged symmetrically with respect to the center line of the cable tower.

[0040] S6. Observe the effect of temperature on the spacing of the joints. When the temperature is relatively stable at night, hoist the first section of the steel anchor box, install it in place and make fine adjustments.

[0041] S7. Pour concrete at the cable tower closure section to complete the cable tower closure and subsequent construction.

[0042] The cable tower concrete segment 1 is provided with a concrete segment segment dividing line 3, which can distinguish each segment. The cable tower steel anchor box segment 2 is also divided by the steel anchor box segment segment dividing line 4.

[0043] The construction method of the present invention has simple procedures and high construction efficiency. The active cross brace also serves as a joint support for the installation of the steel anchor box, which saves temporary structural materials compared to traditional construction, reduces the number of embedded parts of the tower body, and has good economic benefits. The active cross brace is closer to the joint mouth position, and can more effectively adjust the joint mouth spacing, especially in high tower applications. The structure is safe and reliable, and the safety risk is low. The active cross brace adjusts the joint mouth spacing through a jack before the steel anchor box is installed, which not only ensures the installation accuracy of the steel anchor box, but also ensures the joint line shape of the cable tower and the force safety of the structure after the bridge is completed; at the same time, the active cross brace rods and the frame structure provide a support platform for the installation of the steel anchor box and the joint of the cable tower. The present invention solves the problems of precise alignment and jointing of the steel anchor box during high-altitude installation, can improve the installation accuracy of the steel anchor box, ensure the line shape of the cable tower after the joint, ensure the force safety of the structure after the bridge is completed, greatly improve the construction efficiency and construction quality, and has great promotion value.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method for installing a closure bracket for an active horizontal brace of a cable-stayed bridge tower and also serving as a steel anchor box, characterized in that: The method comprises the following steps: S1. The lower tower column of the cable tower is constructed with traditional cross bracing; S2. When pouring concrete of the section before the closure of the cable tower, embed the climbing cone in advance; S3. After the concrete pouring is completed and reaches the designed strength, install the operating platform and active cross brace; S4. Adjust the spacing between the closures by applying the jacking force of the horizontal support jack on the operating platform; S5. Install the distribution beam and bent structure on the active cross brace; S6. Observe the influence of temperature on the spacing of the joints. When the temperature is relatively stable at night, hoist the first section of the steel anchor box, install it in place and make fine adjustments. S7. Pour concrete at the cable tower closure section to complete the cable tower closure and subsequent construction.

2. The construction method of the active cross brace of the cable-stayed bridge tower and also used as a steel anchor box installation joint bracket according to claim 1 is characterized by: In step S1, a traditional cross brace is a pre-embedded climbing cone when pouring the cable tower concrete, and a corbel is set. One end of the steel pipe cross brace is placed on the corbel and fastened to the tower body pad, and the other end is placed on the corbel and fastened to the tower body pad through a jack. The jacking force is applied by the jack to ensure that the tensile stress and linear shape of the tower column meet the requirements of the specification during the construction process.

3. The construction method of the active cross brace of the cable-stayed bridge tower and also used as a steel anchor box installation closure bracket according to claim 1 is characterized by: In step S3, the active cross brace is made of section steel, one end of the section steel cross brace is placed on the corbel and fastened to the tower body pad, and the other end is placed on the corbel and fastened to the tower body pad through a jack.

4. The construction method of the active cross brace of the cable-stayed bridge tower and also used as a steel anchor box installation closure bracket according to claim 3 is characterized by: In step S3, a jack pad is provided between the jack and the cable tower concrete segment, and a cross brace limiter is provided on the active cross brace.

5. The construction method of the active cross brace of the cable-stayed bridge tower also serving as a steel anchor box installation closure bracket according to claim 1 is characterized by: In step S5, the distribution beams and the bent structures are arranged symmetrically about the center line of the tower.

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