Abstract
The objective of this paper is to study the behaviour of mixed structures made of load-bearing masonry and reinforced concrete frames. These structural systems are found in many countries located in seismic areas, including in Romania. The mixed structural system can be used for civil, industrial or agricultural constructions and is of great technical and economic importance. Although they are often found in practice, in many situations these structures are treated wrongly regarding their conformation, but also their behaviour. Load-bearing masonry develops a strong interaction with reinforced concrete frames under the action of seismic forces, and this approach can lead to a substantial inaccuracy in specifying the real seismic response of structures in terms of lateral stiffness, strength and ductility.