Identification of structural parameters and boundary conditions using a minimum number of measurement points

• Published in: Frontiers of Structural and Civil Engineering Vol. 14; no. 6; pp. 1331 - 1348
• Main Authors: KARIMPOUR, Ali, RAHMATALLA, Salam
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 2020; Springer Nature B.V
• Subjects: Boundary conditions; Bridge foundations; Cities; Civil Engineering; Countries; Datasets; eigenvalue problem; Engineering; Euler-Bernoulli beams; Highway bridges; inverse problems; Iterative methods; Mathematical models; Nodes; Numerical models; Parameter identification; Parameter sensitivity; Physical properties; Power spectral density; Regions; Regression analysis; Research Article; Resonant frequencies; response surface; structural model validation; response surface; structural model validation; inverse problems; eigenvalue problem
• ISSN: 2095-2430; 2095-2449
• DOI: 10.1007/s11709-020-0686-4

This article proposes a novel methodology that uses mathematical and numerical models of a structure to build a data set and determine crucial nodes that possess the highest sensitivity. Regression surfaces between the structural parameters and structural output features, represented by the natural frequencies of the structure and local transmissibility, are built using the numerical data set. A description of a possible experimental application is provided, where sensors are mounted at crucial nodes, and the natural frequencies and local transmissibility at each natural frequency are determined from the power spectral density and the power spectral density ratios of the sensor responses, respectively. An inverse iterative process is then applied to identify the structural parameters by matching the experimental features with the available parameters in the myriad numerical data set. Three examples are presented to demonstrate the feasibility and efficacy of the proposed methodology. The results reveal that the method was able to accurately identify the boundary coefficients and physical parameters of the Euler-Bernoulli beam as well as a highway bridge model with elastic foundations using only two measurement points. It is expected that the proposed method will have practical applications in the identification and analysis of restored structural systems with unknown parameters and boundary coefficients.