Reinforced Concrete Structure


Disaster Science And Enginnering


Osman Fatih BAYRAK M. Sc.
Prof. Dr. Murat BIKCE



Accepted Date

Jun 18, 2018

In reinforced concrete buildings, the openings between frames are generally filled by using infill material and by plastering the sides. This application is called infill wall, and it is widely acknowledged as a non-structural element. Therefore, infill walls are often designed assuming that they do not have any effect on the structure other than their weight. However, several experimental and theoretical studies have documented that infill walls, in fact, affect the behavior of a structure under vertical and horizontal loads along with its dynamic characteristics such as its stiffness, period and damping. This study aims to investigate the effect of infill walls on the earthquake performance of a selected building. The structure with and without infill walls has been modelled in SAP2000 structural analysis software and the pushover analysis has been carried out. The infill walls have been modelled as commonly used diagonal bracing without any tensile capacity, which are compatible to their actual behavior. As a result of the comparison of the analyses, infill walls have been found to increase the earthquake performance of the structure, limit the displacement and contribute to the base shear force.

Modellings without infill wall & with infill wall

Formation of hinges model without infill wall & model with infill wall

Base shear force-top displacement graphs of the models with and without an infill wall

As a result of the analysis of a building in the center of Iskenderun carried out by Sap2000 software, infill walls have been found to affect base shear force by up to 40 %. The nonlinear pushover analyses have also revealed that infill walls increase the performance of the structure. The forming of hinges in the structure in which infill walls have been modelled reveals that infill walls are effective in absorbing horizontal earthquake energy, which also means infill walls have an effect on the performance of the existing buildings. Instead of ignoring the stiffness and strength of walls in the calculations in commercial softwares, infill walls should be considered in analyses and assessed in terms of the behavior of a structure in an earthquake, which has an utmost importance for Turkey, an earthquake prone country. In that sense, architects and engineers should cooperate and design commercial stores in buildings by keeping economy and safety at an optimum level. It should not be forgotten that in commercial software designs in which infill walls are considered as load, the model and the actual structure will not behave in the same way under earthquake force.