Methods and Approaches for Blind Test Predictions of Out-of-Plane Behavior of Masonry Walls: A Numerical Comparative Study

ABSTRACT

Earthquakes cause severe damage to masonry structures due to inertial forces acting in the normal direction to the plane of the walls. The out-of-plane behavior of masonry walls is complex and depends on several parameters, such as material and geometric properties of walls, connections between structural elements, the characteristics of the input motions, among others. Different analytical methods and advanced numerical modeling are usually used for evaluating the out-of-plane behavior of masonry structures. Furthermore, different types of structural analysis can be adopted for this complex behavior, such as limit analysis, pushover, or nonlinear dynamic analysis.

Aiming to evaluate the capabilities of different approaches to similar problems, blind predictions were made using different approaches. For this purpose, two idealized structures were tested on a shaking table and several experts on masonry structures were invited to present blind predictions on the response of the structures, aiming at evaluating the available tools for the out-of-plane assessment of masonry structures. This article presents the results of the blind test predictions and the comparison with the experimental results, namely in terms of formed collapsed mechanisms and control outputs (PGA or maximum displacements), taking into account the selected tools to perform the analysis.

KEYWORDS:

• masonry
• numerical analysis
• out-of-plane
• predictions
• seismic performance

Acknowledgement

The authors acknowledge all who submitted and participated in the blind predictions, namely Alessandra Genoese from Roma Tre University, Ana Simões, Ph.D. student of Instituto Superior Técnico, Andrej Anžlin and Miha Kramar from ZAG, Omar AlShawa from Sapienza-Università di Roma, Serena Cattari, Stefania Degli Abbati and Daria Ottonelli from the University of Genova, and Gabriele Milani from the Polytechnic of Milan. The authors also acknowledge the National Laboratory for Civil Engineering (LNEC, Portugal) by all tests carried out.