INFLUENCE OF MASONRY INFILLS ON DYNAMIC BEHAVIOUR OF REINFORCED CONCRETE FRAMED STRUCTURE

Presence of masonry infill walls in R.C. buildings is very common. For horizontal loading, infill panels can drastically modify the response, attracting forces to parts of the structure that have not been designed to resist to them. However, in the design of new buildings and in the assessment of existing ones, even today these infill walls are usually considered as non-structural elements and their influence in the structural response is generally ignored, even though modeling tools, familiar to structural designers, are well able to take care of them with reasonable computational costs. This work aims to show the effects of non-structural masonry infills on the dynamic behaviour of reinforced concrete framed structures. As a first step, a recent macro-model from the literature is selected and a state of the art of the main structural identification issues involving this modeling approach is discussed. The macro model is adopted to simulate, by means of a widely available commercial finite element computer code, an experimental campaign on a four-storey full scale reinforced concrete frame, carried out at the European Laboratory for Structural Assessment (ELSA) of the Joint Research Center of the European Commission in Ispra (VA) Italy. A comparison between the outcome from numerical simulations with code prescribed performance levels and the outcome of the physical testing is presented and discussed.