Investigating the operational modal response and updating the finite element model of a prototype stone structure

Abstract

In this work, the analysis of the dynamic behavior of a prototype stone structure has been presented in two ways: (1) the first way is to instrument the structure with two three-component velocity sensors to measure the structure's response to ambient solicitations. An acquisition and processing chain has been developed in our laboratory to record the acquired vibratory signals. The data processing is obtained using different methods of operational modal analysis (OMA) such as Frequency Domain Decomposition (FDD), Random Decrement Technique (RDT), and Stochastic Subspace Identification (SSI). The results obtained by these methods allowed us to extract the modal parameters (damping and natural frequency) of the structure. (2) The second way consists of characterizing the structure's dynamic behavior in a numerical way using Finite Element Modeling (FEM). However, it has often been noted that the experimental dynamic characteristics obtained do not agree with those of the numerical model. The present study aims to extract the dynamic parameters experimentally and numerically and to update the finite element model for stone construction. A good agreement was found between the two approaches.