Method for simplifying analysis model of fatigue loading effect of orthotropic steel bridge deck

Abstract

The invention discloses a method for simplifying an analysis model of a fatigue loading effect of an orthotropic steel bridge deck. The method comprises steps as follows: 10), performing finite element modeling on a large-span cable bearing bridge structure system, and building an overall structure dimension model; 20), building a partial detailed steel box girder model of the overall structure dimension model with a submodel method, and calculating an equivalent stress amplitude exact solution of a steel bridge deck part of the partial detailed steel box girder model; and 30), simplifying the partial detailed steel box girder model into a partial steel bridge deck stressing structure system, performing optimization analysis on a parameter value of the structure system based on the equivalent stress amplitude exact solution obtained in the step 20), and determining a simplified model for analyzing the fatigue loading effect of the steel bridge deck. The simplified model can guarantee the accuracy of a calculation result and improve the calculation efficiency for analyzing the fatigue loading effect of the orthotropic steel bridge deck greatly at the same time.

Description

technical field [0001] The invention belongs to the field of fatigue analysis and design of steel bridge decks of long-span cable load-bearing bridge structures, and in particular relates to a method for simplifying fatigue load effect analysis models of orthotropic steel bridge decks. Background technique [0002] The orthotropic steel bridge deck is composed of three parts: roof, longitudinal ribs and transverse ribs (called diaphragms in flat steel box girders), in which the distribution of longitudinal ribs is generally dense, while the distribution of transverse ribs is relatively loose, resulting in the The vertical and horizontal stiffness of the steel bridge deck is different, which makes the mechanical characteristics of the steel bridge deck show orthotropy. The structural behavior of orthotropic steel bridge decks is very complex. In addition to the role of deck and deck system, it also functions as a part of the main girder. When it is a component, the top plate...

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Problems solved by technology

[0003] Therefore, when performing finite element analysis on the fatigue load effect of orthotropic steel bridge decks, it is usually necessary to establish an overall structural scale model of the long-span cable-bearing bridge structural system. The results are not accurate enough, and the finer division of the unit grid will lead to a huge amount of calculation. Therefore, the sub-model method is often used in the analysis to establish the local fine model of the steel box girder of the overall structural scale model, and the local fine model of the steel box girder is used for calculation. Exact Solution of Fatigue Loading Effects on Orthotropic Steel Bridge Deck

However, the sub-model method also has certain defects: ① its boundary constraints will change due to the continuous change of fatigue load, which makes the calculation process complicated; ② the fine division of its element mesh will also lead to the number of elements reaching hundreds of thousands , so that the calculation amount is still huge

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