Influence of Infill Panels on the Seismic Behaviour of a R/C Frame Designed According to Modern Buildings Codes

It has been broadly shown that presence of infill panels as closing elements of R/C frame buildings has a significant influence on global structural behaviour. Nevertheless, infill elements are not usually considered in the modelling process during the design phase. The present work investigates the effect of infill masonry walls on the dynamic characteristics of a R/C MRF building, designed according to a modern seismic building code, and on its seismic performance at different levels of seismic intensity. An analytical investigation is carried out through eigenvalue analysis on both bare and infilled structure, in order to calibrate the elastic properties of the concrete and infills according to in situ tests; nonlinear static analyses are also performed to characterize the inelastic behaviour. The infill system considerably affects the behaviour of the examined structure, in agreement with earlier studies related to very simple and usually ”unrealistic” structures. This result becomes more reliable due to the consistency between the results of the eigenvalue analysis and the experimental dynamic data.