Results and lessons learned from the buildings which failed under their own weight in Turkey

The Zumrut Apartment Building in Turkey collapsed completely and suddenly on February 2, 2004, killing 92 people. A few months later, on October 29, 2004, cracks occurred on two reinforced concrete columns in the basement of the Altinbasak Apartment Building, about 500 m away from the Zumrut Building. In both cases the collapses occurred spontaneously, and were not related to an earthquake or other external causes. At the end of the investigations performed in situ and on the project documents, the main reasons for the collapse and damage were determined to be the mistakes made in the design load selection, the inappropriate dimensions of the load-carrying members, poor material quality, and poor soil conditions. The main aim of this study was to investigate the causes of the collapse and damage to these two buildings by considering the significant mistakes made during the design and construction stages. In addition, the research and observations performed on the buildings and the results from tests made on specimens taken from them, will be presented in this paper. A discussion of the values obtained from computer models of the buildings using the finite element method is also presented, and their relationship to the damages observed in the buildings, especially on the vertical load-bearing members.