Simple support beam damage and moving force simultaneous identification method under moving load

Abstract

The invention provides a simple support beam damage and moving force simultaneous identification method under a moving load. The simple support beam damage and moving force simultaneous identification method under the moving load includes steps: measuring accelerated speed power responses of a structure in damage status, and using the accelerated speed responses of the structure as power indexes of structure damage and moving force identification; using Chebyshev polynomials to represent the unknown moving load according to a structure numerical model, and using a beam element shape function concept to equalize the moving load to unit node force, and respectively figuring out sensitivity matrixes of the structure accelerated speed responses for damage and moving force parameters; using a responsive difference between each measured structure accelerated speed response and a finite element accelerated speed response which is obtaining through calculation as an objective function by using a sensitivity analysis result in combination, and using a first order Taylor expansion identification equation to perform iteration step by step and simultaneously identify damage and moving force of a simple support beam. The simple support beam damage and moving force simultaneous identification method under the moving load can achieve simultaneous identification of the damage and the moving force only through a small quantity of the measured accelerated speed responses of the structure, and is strong in practicability.

Description

technical field [0001] The invention belongs to the technical field of structural health monitoring, and in particular relates to a method for simultaneously identifying damage and moving force of simply supported beams under moving loads. Background technique [0002] Structural damage identification and external load identification are two important aspects of the structural health monitoring system, which play an important role in structural safety maintenance and safety assessment. Since the vibration characteristics of the structure (such as time history response, frequency response function, natural frequency, mode shape, etc.) are functions of the physical parameters of the structure (such as stiffness, mass, damping, etc.), structural damage means the change of structural parameters, and The change of parameters will inevitably lead to the change of structural vibration characteristics. At present, damage identification methods based on structural vibration informat...

AI Technical Summary

Problems solved by technology

The above methods can solve the simultaneous identification of unknown loads and structural damage, but are limited to dynamic load identification at fixed positions

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