Seismic performance of the infill masonry walls and ambient vibration tests after the Ghorka 2015, Nepal earthquake

Recent earthquakes have demonstrated a significant contribution of the masonry infill walls in the structural response of the reinforced concrete (RC) buildings. Field observations after the 25th April’s earthquake in Nepal reinforce the conclusion regarding the influence of the infill walls increasing significantly the structural stiffness, which has a direct impact on the natural frequencies of the structure and of structural elements. Firstly the manuscript focuses on the performance of the infilled RC structures, describing common Nepalese architectural configurations and the major damages observed in infilled RC buildings. Secondly, it shows results from data collected on ambient vibration tests performed in seven infill panels with different characteristics, such as geometric dimensions, openings and levels of damage. These results are used to study the influence of each parameter in the out-of-plane frequency of the wall panels. The present studies along the manuscript are followed by a presentation of the study cases (buildings and the walls), test setups, main results and conclusions.

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