Out-of-plane shaketable testing of unreinforced masonry walls in two-way bending

Modelling rocking response via equivalent viscous damping

“…• the rocking problem is formulated in a fashion very similar to the one of a classic elastic oscillator (EO), more familiar to engineers, while accounting for the major differences between the two systems highlighted in Makris and Konstantinidis 17 ; • its implementation in already available finite-element environments is straightforward and will simplify a comparison with static-equivalent code procedures; • modelling both the pre-cracking (ie, before full development of mechanism) and the post-cracking response of walls responding in one-way 33 or two-way bending [34][35][36] is possible. During post-cracking behaviour, the overall dissipated energy is given primarily by impacts and secondary by some hysteretic dissipation, both accounted for by the proposed EVD models; • accounting for additional sources of viscous energy dissipation, such as related to the response of attached horizontal structures, is streamlined 37 ; • a reduced computational effort is necessary, allowing to perform large numbers of nonlinear time-history analyses, such as those necessary to assess the risk for economic and human losses.…”

Influence of traditional earthquake-resistant techniques on the out-of-plane behaviour of stone masonry walls: Experimental and numerical assessment

“…Regarding experimental quasi-static tests, several examples can be found in Ferreira [17] and Dizhur [18]. Vakulik [19] carried out shaking table tests on half-scale two-way spanning unreinforced masonry walls (clay bricks walls) obtaining a good agreement with previous quasi-static tests [20] in terms of peak load, stiffness/strength degradation and damage patterns. Maccarini [21] also carried out an experimental campaign aiming at the characterization of the out-of-plane behaviour of unreinforced stone masonry walls at the University of Minho (Portugal).…”

In-Plane Behaviour of Masonry Walls: Numerical Analysis and Design Formulations

“…In general, local failures mean the activation of out-of-plane mechanisms involving masonry elements that are exposed to seismic actions orthogonally to their plane. Several studies [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ] and experiences from past earthquakes have shown that the vulnerability of masonry buildings to out-of-plane mechanisms is emphasized by the lacking or weakness of connections between elements (i.e., between walls or between walls and horizontal diaphragms). On the other hand, global failure modes only occur in masonry buildings when the in-plane strengths of their earthquake-resistant elements can be activated, i.e., when the connections are able to guarantee a ‘box’ behaviour for the whole building such that seismic actions are, thus, mainly transferred to the walls parallel to each other.…”