Damage identification of a 3D full scale steel–concrete composite structure with partial‐strength joints at different pseudo‐dynamic load levels

Abstract

International audiencePartial-strength composite steel-concrete moment-resisting (MR) frame structures represent an open research field in seismic design from both a theoretical and an experimental standpoint. Among experimental techniques, vibration testing is a well-known and powerful technique for damage detection, localization and quantification, where actual modal parameters of a structure at different states can be determined from test data by using system identification methods. However, the identification of semi-rigid connections in framed structures is limited, and hence this paper focuses on a series of vibration experiments that were carried out on a realistic MR frame structure, following the application of pseudo-dynamic and quasi-static cyclic loadings at the European laboratory for structural assessment of the Joint Research Centre at Ispra, Italy, with the scope of understanding the structural behaviour and identifying changes in the dynamic response. From the forced vibration response, natural frequencies, damping ratios, modal displacements and rotations were extracted using the circle fitting technique. These modal parameters were used for local and global damage identification by updating a 3D finite element model of the intact structure. The identified results were then correlated with observations performed on the structure to understand further the underlying damage mechanisms. Finally, the latin hypercube sampling technique, a variant of the Monte Carlo method, was employed in order to study the sensitivity of the updated parameters of the 3D model to noise on the modal inputs

Identification, Model Updating, and Validation of a Steel Twin Deck Curved Cable‐Stayed Footbridge

“…Due to limitations of FE modeling applied to complex structures, we know that FE models can be improved using experimental data from the identification process. In this respect, model updating approaches based on sensitivity (Brownjohn and Xia, 2000;Moaveni et al, 2009) and Powell's dog-leg (DL) techniques (Molinari et al, 2009;Savadkoohi et al, 2011) have shown advantages. The updated FE model of CSBs should be validated under typical load conditions.…”

Detection of infill wall damage due to earthquakes from vibration data

“…A comprehensive literature review about vibration-based methods for damage detection can be found in. [1][2][3] Among them, the response-based methods are the most adopted ones, even if they present some challenges in real building applications [4] related to the location and the extent of damage (detection of structural and/or non-structural damaged components), the sensitivity of the dynamic response to damage, the choice of damage indexes to be used, the sensor locations, etc. However, although this strategy is widely recognised to be of useful application, a relatively low number of works can be found dealing with applications on real or scaled structures.…”

“…However, although this strategy is widely recognised to be of useful application, a relatively low number of works can be found dealing with applications on real or scaled structures. Some authors performed vibration-based tests on real buildings during the gradual artificially induced damage to both structural and non-structural components [5][6][7] or due to earthquakes, [8,9] while others investigated the modal property evolutions of laboratory specimens representative of Reinforced Concrete (RC), [10][11][12][13][14] steel, [15,16] and steel-concrete composite structures [4,17] subjected to displacements and forces such as to produce structural and non-structural damage. However, a lack of works dealing with damage evaluation of infilled structures by using vibration-based techniques can be observed in the literature.…”

Torsional control of asymmetric buildings using online 3‐D damage detection and adaptive stiffness devices

“…[41][42][43][44][45] On the contrary, in the field of identifying structural parameters in 3-D including damping and stiffness matrices, there are few researches which are reviewed below. Molinari et al 46 identified damages in a 3-D full-scale composite structure using the circle fitting and the finite element model updating technique. Omrani et al 47 presented a method to identify lateral stiffness of torsionally coupled shear buildings by considering the forces equilibrium during a time interval.…”