ABSTRACT –
Over the past several decades, Turkey has been hit by several moderate to large devastating
earthquakes that resulted in significant loss of life and property. Remarkable number of
casualties and heavily damaged or collapsed buildings has emphasized inadequate seismic
performance of multistory reinforced concrete buildings, typically three to seven stories in
height. The aim of this study is to evaluate the seismic performance of the mid-rise reinforced
concrete buildings that are major part of building stock of our earthquake-prone country,
considering nonlinear behavior of reinforced concrete components as well as masonry infill
walls. A sample building set is designed according to 1975 Turkish Earthquake Code to reflect
existing possible construction practice; regular buildings and buildings with irregularities
such as soft story, heavy overhangs, short columns, and soft story with heavy overhangs.
Ductile and non-ductile details are taken into account by transverse reinforcement amount
(transverse reinforcement spacing of 100 mm and 200 mm). Capacity curves of investigated
building set are determined by pushover analyses conducted in two principal directions. The
inelastic dynamic characteristics are represented by equivalent single-degree-of-freedom (SDOF) systems. Their seismic displacement demands are determined using nonlinear
response history analysis under selected ground motions. Seismic performance evaluation is
carried out in accordance with recently published Turkish Earthquake Code (2007). Analytical
damage evaluation in this study has shown that the seismic effects of earthquakes experienced
in Turkey are significant and some of the earthquakes impose excessive displacement demands.
Therefore, considerable portion of existing building stock may not be safe enough in Turkey.
Also, it is observed that structural irregularities affect seismic performance of buildings.
Keywords: Reinforced concrete building stock, Buildings, Earthquake damages, Nonlinear static and
dynamic analysis.