Main beam section pneumatic self excitation force whole-course numerical modeling method

Abstract

The invention relates to a girder section pneumatic self-excitation force full-process value simulation method, aiming at solving the problem that the time-domain of girder section pneumatic self-excitation force is a difficult point for bridge buffeting time-domain analysis and realizing the feasibility and the validity of a pneumatic self-excitation force time-domain method . On the basis of existing dynamic equation derivation, a unit-Aero-dyn18 unit which is specially used for simulating pneumatic rigidity and dynamic damp is established and the relevant parameters, the characteristics and the structure sketch map of the unit are provided. The additionally arranged Aero-dyn18 unit on the basis of a bridge structure finite element initial model and the adoption of a CFD technique to define the relevant parameters of the Aero-dyn18 unit can realize the full-process value simulation to the girder section pneumatic self-excitation force. Compared with the existing pneumatic self-excitation force time-domain method, the method is simple and practical, the analysis efficiency is largely enhanced and the cost is saved at the same time. The method can be easily generalized and adopted by engineering staff.

Description

technical field [0001] The invention relates to a whole-process numerical simulation method of the aerodynamic self-excited force of the main girder section, which is especially suitable for simulating the aerodynamic self-excited force on the main girder section during the time-domain analysis of the chattering response of the bridge. Background technique [0002] With the increasing span of bridge structures, the buffeting analysis of bridges becomes more and more important. There are mainly two types of analysis methods in frequency domain and time domain for chattering response calculation. Early buffeting analysis of bridges at home and abroad was mainly carried out in the frequency domain, but because the frequency domain method can only include a certain number of modes in the analysis process, the statistical characteristics of the structural response value can be obtained, and only linear analysis can be performed. It cannot be well applied to nonlinear structural ...

AI Technical Summary

Problems solved by technology

[0005] (1) Since the existing general-purpose finite element software does not necessarily have a special aerodynamic self-excited force unit, other matrix units with similar characteristics are usually used to simulate the self-excited force in chattering analysis, resulting in increased calculation workload, The probability of error increases, the accuracy of the result decreases, and it is inconvenient to use;

[0006] (2) The aerodynamic stiffness and aerodynamic damping matrix of the main beam unit usually use the aerodynamic derivative obtained in the wind tunnel test as a parameter. Dynamics, CFD) technology in the identification of the latest research results in the field of aerodynamic derivatives has not been fully applied

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