Author
G C MANOS1, ? THAUAMPTEH2 and V J SOULIS2
1 Professor, Department of Civil Engineering, Aristotle University of Thessaloniki, Thessaloniki,Greece
2 Research Assistant, Department of Civil Engineering, Aristotle University of Thessaloniki, Thessaloniki,Greece

Abstract
The hysteretic behaviour of reinforced concrete (RC) frames with masonry infills when they are subjected to horizontal cyclic loads is studied here. An inelastic finite element simulation is employed, including stiffness and strength degradation. This is done by simulating the damage of the masonry infill, the formation of plastic hinges for the RC frame at pre-defined locations and the sliding or the separation of the masonry infill from the surrounding RC frame. A macro-modelling technique is adopted for the simulation of the masonry infills. A number of non-linear spring elements were used to simulate the interface between the RC frame and the masonry infill, while thick beam elements were used to simulate the surrounding frame. Non-linear springs were also employed to simulate the formation of plastic hinges at the RC beam or columns. The effectiveness of this simulation was evaluated by comparing the predicted behaviour with the results from a series of pseudo-dynamic tests whereby a number of 1:3 scale, one bay – one storey RC frames with masonry infills were subjected to horizontal cyclic loads. During these tests the cyclic behaviour of the RC frames was recorded with or without masonry infills. Summary results from this comparison are presented and discussed. It is demonstrated that the numerical simulation employed can successfully predict the observed response.

Key words
Masonry infills, Cyclic loads