Method for hoisting object of asymmetrical structure

Abstract

The invention discloses a method for hoisting an object of an asymmetrical structure. The method comprises the steps that (1), the position of the geometric center line and the position of the actual gravity center line of the object of the asymmetrical structure and the offset direction and offset distance of the actual gravity center line relative to the geometric center line are calculated and determined; (2), a cantilever crane which is fixed to a hoisting platform based on the determined geometric center line in advance and used for hoisting the object of the asymmetrical structure is moved by the offset distance in the offset direction, so that the hoisting gravity center line of the cantilever crane and the determined geometric center line coincide; (3), a special hoisting tool which is suspended along the hoisting gravity center line of the cantilever crane and used for hoisting the object of the asymmetrical structure is provided so that the object of the asymmetrical structure can be kept balanced when hoisted; (4), the special hoisting tool is fixedly connected with the object of the asymmetrical structure, and then hoisting operation is conducted, so that the object of the asymmetrical structure is kept balanced when hoisted.

Description

technical field [0001] The invention relates to the field of road and bridge construction, in particular to a lifting method for structurally asymmetrical objects. Background technique [0002] On the premise that the object is homogeneous, the center of gravity or the line of the center of gravity of the object is only related to its shape. For an object with a regular shape, its geometric center line and the line of the center of gravity coincide; for an object with an irregular shape, the center of gravity of the object The line can be obtained by calculation or experimental methods, and the position of the center of gravity obtained by calculation is also the geometric center and mass center of the irregularly shaped object. When the object is heterogeneous, the geometric center (line) and the actual center of gravity (line) of the object do not coincide. [0003] For partially pre-assembled building components, the contour shape of its surface is approximately regular ...

AI Technical Summary

Problems solved by technology

However, its disadvantages are also prominent. Because in order to obtain a reasonable stress angle, the angle of the inclined rod is usually not less than 45°, so the overall working height of the spreader III is relatively large, and there are requirements for the working clearance height, so it can only be used with some models. The use of cantilever crane IV;

[0009] Second, the pole-type hydraulically adjustable spreader, its main principle is to use the characteristics of better bending and tensile stress of steel, which is the same as the conventional pole beam. By selecting different cross-sections to meet the required working load, it can be moved by moving The hydraulic torque conversion system that changes the position of the lifting center of gravity realizes the transfer of the center of gravity; the shoulder-type hydraulic adjustable spreader has low requirements for working height, and can easily realize the lifting of asymmetric steel box girders (or other building components). However, due to the hydraulic system The introduction of the new system will make its structure more complicated, which will increase the cost of the spreader and the cost of later maintenance and repair. Moreover, the adjustable range of the hydraulic torque conversion system is limited, and the position of the anchor point cannot be changed. When the position of the steel box girder lifting point occurs Unavailable when changed

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