Calculation of Dynamic Response Sensitivity to Substructural Damage Identification under Moving Load

Abstract

In traditional structural damage identification methods, it is usually time consuming to identify a large number of unknown parameters on a large-scale structure. This paper proposes a substructural method to identify the local damage of the large and complex systems. The structural damage, the external moving force and interface forces of adjacent substructures are identified simultaneously from the measured dynamic acceleration responses. The dynamic response sensitivities with respect to the structural parameters and the orthogonal factors of the moving force and interface forces are derived in the state space domain. The proposed method is verified by a simple supported beam and a three-storey frame. Numerical results have shown that the external force, interface force and the structural local damages can be identified by the proposed method effectively and efficiently. Since the concerned substructure is independent and the interface from remaining substructures can be identified, the concerned substructure can be singled out to be used for a large number of substructural analysis.

A Novel Coupled State/Input/Parameter Identification Method for Linear Structural Systems

“…The drift is caused by acceleration's insensitivity to any quasi-static component in the input force [21,22]. Although some regularization methods or postsignal processing schemes can be adopted to deal with the drift in the identified results [33][34][35][36], they are not suitable for the real-time identification of coupled state/input/parameter. In [38], a method dealing with joint state and parameter identification was presented.…”

“…However, it has been demonstrated that the conventional GDF approach based on limited number of acceleration measurements is inherently unstable which leads to the so-called spurious low-frequency drift in the estimates of the force and the structural displacement [22]. Although some regularization methods or postsignal processing schemes can be adopted to deal with the drift in the identified results [33][34][35][36], they prohibit the real-time identification of coupled state/input/parameter.…”

Damage Identification for Underground Structure Based on Frequency Response Function

“…In the case of a damaged structure, the stiffness matrices after damage according to Equations (6) and (7), is commonly expressed, as follows: where is the stiffness matrices before damage, is the stiffness matrices after damage, and is the variation in the stiffness matrices after damage. Furthermore, the damping matrices are commonly considered constant with the damage that occurs, and the degradation of mass ( ) is regarded as zero [ 48 , 49 , 50 ].…”

Damage Identification in Bridges by Processing Dynamic Responses to Moving Loads: Features and Evaluation

“…Various studies have demonstrated that the dynamic characteristics of bridges bearing cracks due to moving loads convey sufficient information about damage [14,16]. The dynamic characteristics used to portray damage may involve deflection [17,18,19,20,21,22,23], mode shape [24,25,26], acceleration [27,28,29], moving principal component analysis [30,31], energy ratio of the vibrational response [32], virtual distortion [33], dynamic response sensitivity [34], footprints of the dynamic amplification factor [35], differences in modal curvature [36], and strain sensing [37]. It is worth mentioning that Majumder and Manohar [38] presented a time domain approach for utilizing vibration data induced by a moving vehicle to assess damage in bridge structures based on the framework of finite element modeling.…”