Fragility Assessment of Masonry-Infilled RC Frames Strengthened by HPFRCC

The past earthquakes show the vulnerability of many framed structures with masonry infills. Thus, strengthening requirements of a large number of existing buildings should be considered using an effective, compatible and applicable approach. Recently, high performance fiber reinforced cementitious composites (HPFRCC) as a strengthening overlay on masonry infill walls has been developed. In this paper, the numerical modeling of masonry infilled reinforcement concrete frame is carried out before and after strengthening with a special kind of HPFRCC called Engineered Cementitious Composites using DIANA FEA software. After numerical modeling of the specimens based on micro modeling approach and nonlinear dynamic analysis by considering 14 earthquake records, seismic evaluation of RC frames is represented using fragility curves. The results illustrate that the ECC layer increases stiffness and strength of infilled frames. Furthermore, by reducing the damage probability of the strengthened RC frames, the damage mechanisms of the masonry walls is changed.