Nonlinear analysis and FRP strengthening of multi-storey infilled RC building

Existing reinforced concrete buildings in the Mediterranean area are vulnerable to seismic actions and they commonly exhibited significant damage to structural and non-structural components. The brittle failures of beam-column joint or columns due to the frame effect or the interaction with stiff infill walls commonly limit the building lateral response. Further-more, repairing the damage to infill and partitions is a relevant portion of the total repair cost. These weaknesses may result in number of casualties and relevant economic losses re-marking the need to introduce reliable strengthening solutions capable of improving the building safety and reducing the damage to non-structural components.To investigate the seismic response of existing RC frame and the interaction between the structural system and the infill wall an experimental program on a multistorey RC infilled frame has been designed. An existing RC building severely damaged by the L’Aquila earth-quake is selected for this study. This paper illustrated the preliminary numerical simulations at building and frame level carried-out to design the experimental program. Refined numeri-cal modelling including the nonlinearities of frame members, beam-column joints and infill walls is used. The numerical analyses of the frame in the bare and infilled configuration are reported and discussed with reference to the accuracy of the model to capture the observed earthquake damage. In conclusion, the influence of a strengthening solution by using FRP systems at level of joint and top-end of column is numerically assessed.