Vibration-based damage identification of an unreinforced masonry house model

Abstract

Non-destructive vibration-based damage identification techniques are especially attractive for assessing damage in structures of high historical and architectural value. So far, most studies have focused on slender structures built using relatively homogeneous materials. In this study, global damage identification methods based on vibration response parameters were applied for identifying damage in an unreinforced masonry full-scale house model (non-homogeneous material and non-slender structure). The house model was dynamically loaded using an eccentric-mass shaker. Structural damage to the walls was initiated by increasing the amplitude of the applied load. At each damage state, a modal test was performed by impacting the walls with a calibrated hammer. Statistically significant variations of modal frequencies and the modal assurance criteria were considered as suitable parameters to identify damage. It was concluded that different sets of modes can be found for different states of damage because of material degradation, change in the support and connectivity conditions, and breaks in the members continuity generated by damage. All these changes are reflected in variations of modal frequencies and modal assurance criteria. It was also established that prior to identifying the damage distribution on the entire building, it was necessary to determine how the modal frequencies were related to each wall.

Improving in-plane seismic response of unreinforced masonry walls using steel strips

“…Moderate to strong earthquakes cause damage to existing masonry buildings which have not been constructed to resist earthquake forces, as depicted in Figure 1 (Ahmadizadeh and Shakib, 2004; Baitao and Guixin, 2018; Baitao and Peilei, 2015; Ferreira et al, 2017; Hao et al, 2016; Jingya et al, 2013; Kaplan et al, 2010; Lin et al, 2017; Okamura et al, 2015; Oyarzo-Vera et al, 2017; Preciado and Orduna, 2014; Tama et al, 2013; Wenfeng et al, 2017). Worldwide, various techniques have been proposed and applied for seismic retrofitting of unreinforced masonry (URM) walls such as reinforcement centercore, confinement with reinforced concrete (RC) strips, adding RC layers, fiber-reinforced polymer (FRP) layers, fiber-reinforced cementitious composite shotcrete, twisted stainless steel near surface mounted (TSNSM), post-tensioning, and external reinforcement.…”

Numerical Modeling of Masonry Infilled Reinforced Concrete Building during Construction Stages Using ABAQUS Software

“…After that, the results obtained from the measurements can be considered almost accurate [1]. The application of well-known different identification techniques include: The Crystal-Clear Stochastic Subspace Identification (CC-SSI) method [2], the Stochastic Subspace Identification (SSI) method [3], and the Enhanced Frequency Domain Decomposition (EFDD) method [4]. The use of the ambient vibration measurements has been proven to be relatively fast, cost reducing and economically efficient for the determination of dynamic characteristics [5].…”

Sensitivity to Damage Imperfection for Multileaf Masonry Walls Based on Vibrational Analyses

“…Laboratory tests have been proposed to improve methodologies for dynamic identification and damage detection of existing masonry structures, both on full-scale masonry buildings [15] and on masonry wall panels [16,17], with attention focused on damage indicators. In particular, in the work [17], damage has been specifically induced in a masonry panel and the modal response of the specimens has been extracted in order to evaluate the structural health for different levels of damage, with the purpose of detecting possible correlations between variations in the modal properties and the entity of the damage.…”