Large-span super-heavy plate girder overturning and hoisting method

Abstract

The present application relates to a kind of large-span super heavy plate girder overturning hoisting method, comprising the following steps: one hoisting point position determination, according to specification and actual situation in site determines the range of two hoisting point distance, the stress distribution of plate girder is calculated using finite element software analysis different hoisting point position, select the best hoisting point position of two large hoist;Two small hoist use determination, whether need to set up small hoist in the middle during overturning process is calculated using finite element software analysis;Three determine small hoist connection position, the stress distribution of different position and different stress conditions of small hoist is calculated using finite element software analysis, determine the best connection position;Four overturning hoisting, two end position large hoist first force, small hoist in the middle according to the result follow two end large hoist behind force, overturning is completed, small hoist track field, two end large hoist plate girder is hoisted in place after hook loosening, complete hoisting.The present application solves the problem that plate girder shakes in the overturning process of conventional hoisting method and has potential safety hazard.

Description

A method for flipping and hoisting large-span, ultra-heavy plate beams Technical Field

[0001] This invention relates to the field of large-span heavy beam assembly and installation technology, and in particular to a method for flipping and hoisting large-span ultra-heavy plate beams. Background Technology

[0002] Currently, hoisting and lifting technology is a common technique in steel structure construction sites during structural installation. As the spans and structural complexities of domestic spatial structure projects increase, hoisting technology needs continuous development. Due to transportation limitations, large-span slab beams often need to be fabricated in sections at the factory and then spliced ​​on the construction site. During splicing, the slab beams are in a lying position, and before hoisting, they need to be rotated 90 degrees. Currently, there are two common methods: one is to use a super-large crane to set a lifting point in the middle for direct rotation; the other is to set a lifting point at each of the two ends of the slab beam at 1 / 3 to 1 / 4 of the distance from both ends. The first method has two drawbacks during the rotation process: 1. Stress is concentrated in the middle; 2. Due to the low stiffness of the steel and the characteristic of the slab beam being long in length and narrow in width, severe sagging occurs at both ends during hoisting, resulting in significant shaking and low safety. The second method, with the lifting point set at 1 / 3 to 1 / 4 of the span, results in relatively uniform stress distribution. However, after the flipping process, during hoisting and positioning, because the lifting point is at 1 / 3 to 1 / 4, even slight deviations in synchronization during the dual-crane lifting process can cause uneven stress on the two cranes, compromising safety. Furthermore, during positioning, due to the long length of the slab beam, even slight adjustments to the crane's distance from the beam end result in significant positional variations, making precise placement difficult. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for the overturning and hoisting of large-span, ultra-heavy plate beams, comprising:

[0004] Step 1: Determine the lifting point location. Based on the specifications and actual site conditions, determine the range of distance between the two lifting points. Use finite element software to analyze the stress distribution of the slab beam at different lifting point locations and select the optimal lifting point location for the two large cranes.

[0005] Step 2: Use a crane to determine the optimal lifting point. After determining the optimal lifting point, use finite element software to analyze and calculate whether a small crane needs to be set up in the middle of the flipping process.

[0006] Step 3: Determine the connection position of the small crane, and use finite element software to analyze and calculate the stress distribution of the small crane at different positions and under different stress conditions to determine the optimal connection position;

[0007] Step 4: Tilting and hoisting. The large cranes at both ends exert force first, and the small crane in the middle follows the large cranes at both ends according to the calculation results to complete the tilting of the slab beam. After the tilting is completed, the small crane leaves the parking area, and the large cranes at both ends lift the slab beam into place and then release the hook to complete the hoisting.

[0008] Furthermore, the plate beam is a large plate beam with a weight of 110t or more.

[0009] Furthermore, the length of the plate beam is greater than or equal to 45m, and its flange width is greater than or equal to 0.7m.

[0010] Furthermore, the lifting height of the plate beam is greater than or equal to 10m.

[0011] Furthermore, the lifting capacity of the large crane is greater than or equal to 150t.

[0012] Furthermore, the lifting capacity of the small crane is greater than or equal to 50t.

[0013] Furthermore, in step one, the fluctuation range of the lifting point position is controlled between 1m and 2m.

[0014] Furthermore, in step one, multiple sets of lifting point positions are calculated.

[0015] Furthermore, in step four, the rotation angle of the plate beam is 85°~90°.

[0016] In summary, the beneficial technical effects of this invention are as follows: it solves the potential safety hazards caused by the shaking of the beam during the flipping process in conventional hoisting methods; it guides the selection of cranes and lifting points on site through finite element software simulation, solving the problem of insufficient consideration caused by hasty decisions due to the lack of theoretical support on site; it eliminates the need for ultra-large cranes, saving costs; and it shortens the construction period. Attached Figure Description

[0017] The above and other objects, features, and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings. The drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0018] Figure 1 is a flowchart of the tilting and hoisting method of the present invention;

[0019] Figure 2 is a schematic diagram of the hoisting structure of the present invention from the front view.

[0020] Figure 3 is a schematic diagram of the hoisting side view structure of the present invention;

[0021] Figure 4 shows the hoisting state after the small crane has been removed after the flipping is completed according to the present invention;

[0022] Figure 5 shows the stress distribution of the beam at the lifting point 2 m from the beam end;

[0023] Figure 6 shows the stress distribution of the slab beam during the implementation stage without the small crane being set up in the middle for tilting;

[0024] Figure 7 shows the stress distribution during the initial stage of the small crane's overturning.

[0025] In the diagram, 1 is a large crane, 2 is a small crane, 3 is a slab beam, and 4 is a support beam. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0027] Referring to Figures 1-4, this invention discloses a method for the overturning and hoisting of a large-span, ultra-heavy plate girder, comprising: Step 1, determining the lifting point positions: based on specifications and actual site conditions, determining the range of distance between two lifting points; using finite element analysis software to calculate the stress distribution of the plate girder at different lifting point positions; selecting the optimal lifting point positions for two large cranes 1; Step 2, determining the use of a small crane: after determining the optimal lifting point positions, using finite element analysis software to calculate whether a small crane needs to be set up in the middle during the overturning process; Step 3, determining the connection position of the small crane: using finite element analysis software to calculate the stress distribution of the small crane at different positions and under different stress conditions; determining the optimal connection position; Step 4, overturning and hoisting: the large cranes at both ends exert force first, and the small crane in the middle follows the large cranes at both ends to exert force after the calculation results, completing the overturning of the plate girder. After the overturning is completed, the small crane is parked, and the large cranes at both ends release their hooks after hoisting the plate girder into place, completing the hoisting.

[0028] Furthermore, the plate beam is a large plate beam with a weight of 110t or more.

[0029] Furthermore, the length of the plate beam is greater than or equal to 45m, and its flange width is greater than or equal to 0.7m.

[0030] Furthermore, the lifting height of the plate beam is greater than or equal to 10m.

[0031] Furthermore, the lifting capacity of the large crane is greater than or equal to 150t.

[0032] Furthermore, the lifting capacity of the small crane is greater than or equal to 50t.

[0033] Furthermore, in step one, the fluctuation range of the lifting point position is controlled between 1m and 2m.

[0034] Furthermore, in step one, multiple sets of lifting point positions are calculated.

[0035] Furthermore, in step four, the rotation angle of the plate beam is 85°~90°.

[0036] A preferred embodiment of the large-span, ultra-heavy plate girder tilting and hoisting method of the present invention is as follows:

[0037] This invention primarily targets large-span, ultra-heavy-duty slab beams with a large flange aspect ratio, made of Q355B steel. In a certain industrial plant project in Daewon Province, a slab beam weighed 110 tons, was 48 meters long, had a flange width of 0.8 meters, and a lifting height of 11 meters. Due to transportation requirements, the slab beam was assembled on-site, necessitating a 90-degree rotation before hoisting. This hoisting process is classified as an extremely dangerous and complex project. This invention utilizes finite element analysis software and employs two 150-ton cranes and one 50-ton crane.

[0038] The main steps are as follows:

[0039] Step 1: Use finite element software to analyze the stress distribution of the slab beam during hoisting under different distances between the lifting point and both ends of the slab beam. Determine the optimal lifting point position for the two large cranes during hoisting as 2-3 m from the end of the beam. Figure 5 shows the stress distribution of the beam with the lifting point position 2 m from the end of the beam. It can be seen from the figure that the stress of each part of the slab beam 3 meets the requirements for safe hoisting.

[0040] Step 2: Use finite element software to analyze the stress distribution when the plate beam 3 is flipped. Based on the stress distribution, it is confirmed that a small crane 2 needs to be set in the middle position. Figure 6 shows the stress distribution of the plate beam 1 during the flipping stage without the small crane 2 set in the middle. It can be seen from the figure that the stress is concentrated in the middle position, close to the yield limit of Q355B steel.

[0041] Step 3: Use finite element software to analyze the stress distribution of the plate beam during the flipping process when the deformation at the middle position is 0, the force on the small crane 2, and determine the optimal stress range of the small crane 2. In this case, the reaction force at the middle position is 29.37t. Figure 7 shows the stress distribution in the initial stage of flipping when the small crane 2 is set in the middle to ensure that the deformation at the middle position of the plate beam 1 is 0. As can be seen from the figure, the stress distribution is uniform and meets the requirements.

[0042] Step 4: A 50-ton crane (small crane 2) is set up in the middle to cooperate with the 150-ton cranes (large crane 1) at both ends to complete the flipping of the slab beam 1. Figure 2-4 shows the crane station position diagram during the flipping process of the slab beam. After the flipping is completed, the small crane 2 is put into place, and the two 150-ton cranes (large crane 1) lift and install it in place before releasing the hook to complete the hoisting.

[0043] In summary, the beneficial technical effects of this invention are as follows: it solves the potential safety hazards caused by the shaking of the beam during the flipping process in conventional hoisting methods; it guides the selection of cranes and lifting points on site through finite element software simulation, solving the problem of insufficient consideration caused by hasty decisions due to the lack of theoretical support on site; it eliminates the need for ultra-large cranes, saving costs; and it shortens the construction period.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for the overturning and hoisting of large-span, ultra-heavy plate beams, characterized in that, include: Step 1: Determine the lifting point positions. Based on specifications and actual site conditions, determine the range of distance between the two lifting points. Use finite element analysis software to calculate the stress distribution of the slab beam at different lifting point positions, select the optimal lifting point positions for the two large cranes, and control the fluctuation range of the lifting point positions to between 1m and 2m. Calculate multiple sets of lifting point positions. Step 2: Determine the use of the small crane. After determining the optimal lifting point positions, use finite element analysis software to calculate whether a small crane needs to be set up in the middle during the flipping process. Step 3: Determine the connection position of the small crane. Use finite element analysis software to calculate the stress distribution of the small crane at different positions and under different stress conditions to determine the optimal connection position. Step 4: Flipping and lifting. The large cranes at both ends apply force first, and the small crane in the middle follows the large cranes at both ends according to the calculation results to apply force after the large cranes at both ends, completing the flipping of the slab beam. After flipping, the small crane is removed from the site, and the large cranes at both ends release their hooks after lifting the slab beam into place, completing the lifting.

2. The method for tilting and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, The slab beam is a large slab beam with a weight of 110t or more.

3. The method for tilting and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, The length of the plate beam is greater than or equal to 45m, and its flange width is greater than or equal to 0.7m.

4. The method for tilting and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, The lifting height of the slab beam is greater than or equal to 10m.

5. The method for tilting and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, The lifting capacity of the large crane is greater than or equal to 150t.

6. The method for tilting and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, The lifting capacity of the small crane is greater than or equal to 50t.

7. The method for overturning and hoisting large-span, ultra-heavy plate beams according to claim 1, characterized in that, In step four, the lifting angle of the plate beam is 85° to 90°.

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