Evaluation of the period and soft story conditions of reinforced concrete buildings with and without infill walls

Abstract

Since the ground floor of most of the buildings in our country is designed as a shop or ground floor (in the buildings created as a workplace), there is very little infill wall ratio on the ground floors due to architectural and functional reasons, and some of them do not even exist at all. However, infill walls significantly increase the horizontal rigidity and strength of the structure, thus causing a decrease in the period value that determines the earthquake loads that will affect the structure. However, the infill wall meets the first destructive forces of the earthquake, and during this time, it cracks and absorbs some of the earthquake energy. The structural system elements of the building (columns and shear walls) start to meet the earthquake forces only when the infill walls are damaged and fail. In this direction, the aim of this study is to investigate to what extent the amount of infill wall on the ground floor affects the period of the building, and whether there are soft storey irregularities in the building according to the change in the amount of infill wall on the ground floor. In this study, while there are infill walls on all floors and all axes of buildings of various heights (3, 6, 9 and 11 floors), the amount of infill walls in the x and y directions on the ground floors is reduced to a certain extent, and many models are created until the ground floor is completely without infill walls. All these models created were analyzed with the support of the SAP2000 program, and the period values were determined and examined according to the soft storey problems and compared with the case of the entire building with and without infill walls. In addition, it was examined whether the period formulas determined as a result of the studies and taking into account the infill wall give realistic results for the situation examined in this study.