Construction method for lowering section steel framework of offshore cable bent tower beam

Abstract

The invention provides an offshore cable bent tower beam section steel framework lowering construction method which comprises the steps that a beam section steel framework reserved section, an installation bracket and a guide device located on a cable bent tower section steel framework are installed in place along with the cable bent tower section steel framework at the same time, then the beam section steel framework is lowered, and in the lowering process, the beam section steel framework is installed in place; roughly adjusting the cross beam profile steel framework to the position of a guide notch and guiding the cross beam profile steel framework into the notch, and continuously holding load by the floating crane; longitudinal bridge direction fine adjustment is conducted on the cross beam profile steel framework through a longitudinal bridge direction fine adjustment device, transverse bridge direction fine adjustment is conducted on the cross beam profile steel framework through a transverse bridge direction fine adjustment device, and truss welding is conducted after the cross beam profile steel framework is adjusted to the designed position; the floating crane is withdrawn, and the cross beam profile steel framework is lowered. The lowering construction method of the cross beam type steel framework is improved, the construction difficulty and the high-altitude operation risk are reduced, the cost is saved, the construction period is shortened, the lowering precision of the cross beam type steel framework is improved, the stability and safety of a bridge tower are guaranteed, and good engineering application value is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of cable-stayed bridge tower construction, and in particular relates to a method for lowering a crossbeam steel frame of an offshore tower. Background Art

[0002] For the construction of large offshore cable tower beams, the ground support method is currently widely used. Due to the height of the cable tower beam, the terrain and hydrological environment of the cable tower, the required investment cost is large, the high-altitude operation is risky, and the construction period is long. Although the use of floating cranes can greatly solve the above problems, the floating crane hoisting of large steel structures is affected by wind, tides, waves, and water flow. The shaking will occur during the hoisting process, which will affect the lowering accuracy and subsequent installation and closure. The lowering accuracy of the beam steel frame directly affects the stability and safety of the cable-stayed bridge. Therefore, it is extremely necessary to strictly control the lowering accuracy of the beam steel frame. In view of this, a construction method system for lowering the beam steel frame of an offshore cable tower is proposed. Summary of the invention

[0003] In view of this, the present invention aims to overcome the defects in the prior art and proposes a construction method for lowering a crossbeam steel frame of an offshore cable tower.

[0004] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0005] A construction method for lowering a crossbeam steel frame of an offshore cable tower comprises the following steps:

[0006] S1, the reserved section of the beam steel frame, the installation bracket and the guide device on the cable tower steel frame are installed in place together with the cable tower steel frame, and a gap is left between the reserved section and the beam steel frame for welding and closure;

[0007] S2. Lower the crossbeam steel frame, and during the lowering process, roughly adjust the crossbeam steel frame to the guide slot position and guide it into the slot, and the floating crane continues to hold the load;

[0008] S3. After the slot position is introduced, the longitudinal bridge direction fine adjustment device is used to fine-tune the crossbeam steel frame until it is adjusted to the longitudinal bridge direction design position;

[0009] S4. Fine-adjust the cross-beam steel frame in the transverse direction by using the cross-beam fine-adjusting device until the cross-beam steel frame is adjusted to the designed position;

[0010] S5. After the crossbeam steel frame is adjusted to the designed position, truss welding is performed;

[0011] S6. Withdraw the floating crane and lower the crossbeam steel frame.

[0012] Further, in step S2, the beam steel frame is slowly lowered by a floating crane.

[0013] Further, in step S2, the crossbeam steel frame is adjusted to the guide slot position by a coarse adjustment positioning device and introduced into the slot.

[0014] Furthermore, the coarse adjustment positioning device includes a coarse adjustment jack and a connecting rod on the jack, and the connecting rod is connected to a truss adjacent to the truss where the jack is located.

[0015] Furthermore, the transverse bridge fine-adjusting device includes a jack.

[0016] Furthermore, the longitudinal bridge direction fine-adjusting device includes a jack.

[0017] Furthermore, in step S6, the lower chord and the upper chord of the truss corresponding to the closure hanging point are welded first, and then other trusses are closure-connected.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The present invention improves the construction method of lowering the beam steel frame, reduces the construction difficulty and the risk of high-altitude operations, saves costs, shortens the construction period, improves the lowering accuracy of the beam steel frame, ensures the stability and safety of the bridge tower, and has good engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0021] Figure 1 A schematic diagram of the planar structure when the present invention is created and applied;

[0022] Figure 2 A schematic diagram of the side elevation structure when the present invention is created and applied;

[0023] Figure 3 When hoisting the beam steel frame Figure 1 Schematic diagram of the 1-1 direction;

[0024] Figure 4 After the beam steel frame is in place Figure 1 Schematic diagram of the 1-1 direction;

[0025] Figure 5 When hoisting the beam steel frame Figure 1 Schematic diagram of the 2-2 direction;

[0026] Figure 6 After the beam steel frame is in place Figure 1 Schematic diagram of the 3-3 direction;

[0027] Figure 7 A schematic diagram of the front elevation structure when the present invention is created and applied;

[0028] Figure 8 A schematic diagram of the partial elevation layout of the longitudinal bridge guide device created by the present invention;

[0029] Fig. 9 The present invention provides a schematic elevational layout diagram of the transverse bridge guide device portion.

[0030] Description of reference numerals:

[0031] A-crossbeam steel frame; B-cable tower steel frame; C-crossbeam reserved section; 1-longitudinal bridge guide device; 2-transverse bridge guide device; 3-mounting bracket; 4-coarse adjustment positioning device; 5-longitudinal bridge fine adjustment device; 6-transverse bridge fine adjustment device. DETAILED DESCRIPTION

[0032] 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.

[0033] 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 a limitation on the present invention. In addition, the terms "first", "second", etc. 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", etc. 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.

[0034] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 invention can be understood according to specific circumstances.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0036] A construction method for lowering a crossbeam steel frame of an offshore cable tower, such as Figures 1 to 9 As shown, the following steps are included:

[0037] S1, the reserved section of the beam steel frame, the installation bracket and the guide device on the cable tower steel frame are installed in place together with the cable tower steel frame, and a gap is left between the reserved section and the beam steel frame for welding and closure;

[0038] S2. Lower the crossbeam steel frame, and during the lowering process, roughly adjust the crossbeam steel frame to the guide slot position and guide it into the slot, and the floating crane continues to hold the load;

[0039] S3. After the slot position is introduced, the longitudinal bridge direction fine adjustment device is used to fine-tune the crossbeam steel frame until it is adjusted to the longitudinal bridge direction design position;

[0040] S4. Fine-adjust the cross-beam steel frame in the transverse direction by using the cross-beam fine-adjusting device until the cross-beam steel frame is adjusted to the designed position;

[0041] S5. After the crossbeam steel frame is adjusted to the designed position, truss welding is performed;

[0042] S6. Withdraw the floating crane and lower the crossbeam steel frame.

[0043] In step S2, the beam steel frame is slowly lowered by floating crane. In step S2, the beam steel frame is adjusted to the guide slot position by coarse adjustment positioning device and introduced into the slot. In step S6, the lower chord and upper chord of the truss corresponding to the joint lifting point are welded first, and then other trusses are jointed.

[0044] As an example, the coarse adjustment positioning device includes a coarse adjustment jack and a connecting rod on the jack, and the connecting rod is connected to a truss adjacent to the truss where the jack is located. The transverse bridge direction fine adjustment device includes a jack. The longitudinal bridge direction fine adjustment device includes a jack.

[0045] The present invention improves the construction method of lowering the beam steel frame, reduces the construction difficulty and the risk of high-altitude operations, saves costs, shortens the construction period, improves the lowering accuracy of the beam steel frame, ensures the stability and safety of the bridge tower, has good engineering application value, and provides a reference for the high-altitude precise lowering of the beam steel frame of the cable tower of the cross-sea (or cross-river) bridge.

[0046] 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 lowering a crossbeam steel frame of an offshore cable tower, characterized in that: The steps include: S1, the reserved section of the cross beam steel frame, the installation bracket and the guide device on the cable tower steel frame are installed in place together with the cable tower steel frame, and a gap is left between the reserved section and the cross beam steel frame for welding and closure; S2. Lower the crossbeam steel frame, and during the lowering process, roughly adjust the crossbeam steel frame to the guide slot position and guide it into the slot, and the floating crane continues to hold the load; S3. After the slot position is introduced, the longitudinal bridge direction fine adjustment device is used to fine-tune the crossbeam steel frame until it is adjusted to the longitudinal bridge direction design position; S4. Fine-adjust the cross-beam steel frame in the transverse direction by using the cross-beam fine-adjusting device until the cross-beam steel frame is adjusted to the designed position; S5. After the crossbeam steel frame is adjusted to the designed position, truss welding is performed; S6. Withdraw the floating crane and lower the crossbeam steel frame.

2. The method for lowering the crossbeam steel frame of an offshore cable tower according to claim 1 is characterized in that: In step S2, the beam steel frame is slowly lowered by a floating crane.

3. The method for lowering the crossbeam steel frame of an offshore cable tower according to claim 1 is characterized in that: In step S2, the crossbeam steel frame is adjusted to the guide slot position by a coarse adjustment positioning device and introduced into the slot.

4. The method for lowering the crossbeam steel frame of an offshore cable tower according to claim 3 is characterized in that: The coarse adjustment positioning device comprises a coarse adjustment jack and a connecting rod on the jack, wherein the connecting rod is connected to a truss adjacent to the truss where the jack is located.

5. The method for lowering the crossbeam steel frame of an offshore cable tower according to claim 1 is characterized in that: The transverse bridge fine adjustment device includes a jack.

6. The method for lowering the crossbeam steel frame of an offshore cable tower according to claim 1 is characterized in that: The longitudinal bridge direction fine adjustment device includes a jack.

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