Solutions for infilled masonry buildings: shaking table tests

Abstract

Infilled masonry can be seen as an old research issue, but recent seismic activities, such as the 2009 Aquila earthquake in Italy, showed seismic engineers and structural designers that current infill solutions may not work as expected. In this seismic action, the analysis of the damages in buildings constructed in the last 20 years, designed according to modern standards, may lead to the worrying conclusion that the design Limit States were not fulfilled. Taking this into account, a research program was conducted as a partnership between the University of Minho, Portugal, and the National Laboratory for Civil Engineering (L.N.E.C.), Portugal, which included a shaking table experimental program. The objective of this program was to study the seismic behaviour of the most common infill solution in Portugal, the unreinforced double leaf clay brick masonry, and two reinforced solutions referenced in the standard Eurocode 8: i) single leaf clay brick with bed joint reinforcement, connected to the bounding frame; ii) single leaf clay brick with steel net in the plaster, connected to the bounding frame. The present paper details the first two tested solutions, along with the discussion of the results, focusing on the obtained collapse modes of the infills and the measured accelerations for those modes.