Method for calculating unstressed length of central cable of main cable of space self-anchored suspension bridge

Abstract

The invention discloses a method for calculating the unstressed length of a central cable of a main cable of a space self-anchored suspension bridge. The method is characterized in that a main cable is divided into a plurality of cable sections by taking a lifting point as a boundary, and the method comprises the following steps: firstly, respectively calculating vertical force projected on a vertical surface and horizontal force in a longitudinal bridge direction by tension at the lifting point of each cable section, and a transverse force projected on a horizontal plane and vertical to in the longitudinal bridge direction; solving the unstressed length of the central cable of each cable section according to the vertical force, the horizontal force and the transverse force, and performingaccumulating to obtain the unstressed length of the central cable of the main cable before correction; and obtaining the final corrected main cable center cable unstressed length by adding the main cable center cable length before correction to the main cable center cable unstressed length correction value in the main cable saddle. According to the method, a fine finite element calculation modeldoes not need to be established, the main cable and the lifting point are taken as research objects, the three-way force at the lifting point and the stress-free length of the central cable of the main cable are solved through simple iterative calculation, the algorithm calculation process is relatively simple, the concept is clear, and the calculation precision meets the requirements of engineering design.

Description

technical field [0001] The invention belongs to the field of bridge structure design, and relates to a space self-anchored suspension bridge, in particular to a method for calculating the unstressed length of a central cable of a space self-anchored suspension bridge. Background technique [0002] Suspension bridge is a type of bridge with the largest spanning capacity, and is widely used in long-span bridges. Suspension bridge is a cable-bearing bridge composed of main girder (stiffening girder), main cable, suspension cable, main tower, cable saddle, anchoring structure and other components. Among them, the main cable and suspension cable of the space self-anchored suspension bridge form a three-dimensional cable system, which has good landscape effect, large lateral rigidity, strong wind resistance, and does not need to build a large-volume anchoring structure, and is less restricted by terrain and geology. Advantages, so it has been more and more widely used in urban br...

AI Technical Summary

Problems solved by technology

[0004] 1. The calculation efficiency of finite element method is not high

[0005] The main reasons for the inefficiency of using the finite element method to calculate the stress-free length of the main cable center cable are as follows: it takes a lot of time to establish a fine finite element three-dimensional calculation model, and the setting of boundary conditions requires high professional knowledge in mechanics

[0006] 2. Traditional numerical analysis algorithms still have problems in terms of accuracy and convergence

In fact, under the action of its own weight, it is impossible for the space cable-shaped main cable to be on an inclined plane, so the accuracy of this method is limited

[0009] (2) Complicated calculation and difficult convergence

Although the calculation accuracy of the above algorithm is high, there are still problems of high calculation difficulty and difficult convergence.

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