EFFECTS OF MASONRY INFILL WALLS ON THE SEISMIC RESPONSE OF MULTI-STORY REINFORCED CONCRETE STRUCTURES.

Abstract

Infill masonry walls are considered a secondary element of reinforced concrete structures in many design conditions. In the Albanian design conditions and the Eurocodes, they have been treated as non-structural elements during the design phases of buildings. Neglecting the contribution of the stiffness of these walls can, in some cases, lead to an unsaved project. Infill walls not only perform the dividing function between the interior spaces of a building, but they also affect, in general, the behavior of reinforced concrete structures under seismic loads. This study evaluates the seismic performance of the building by considering the effects of the infill walls. To investigate these effects, five different models of a 6-story building were studied. The influence that these models have, with and without the presence of the walls, has been analyzed. The walls were calculated and modeled as diagonal strud elements according to Fema 356 formulas. The capacity curves of each model were determined by Respons spectrum analysis done in two main directions using the Etabs computer package. The seismic performance assessment was performed in accordance with Eurocode 8, which is similar to the FEMA-356 guidelines. The final results are compared in graphical form for the shear force in relation to the number of stories, the story displacements, story drift, and the stiffness of the structure. In conclusion, after analyzing the results, the effects that these walls have on the structure can be significantly noticed, especially in cases where the infill walls are not considered.