Defects made in project and construction stages of buildings constructed in Kocaeli after the earthquake code-2007

Besides being a natural disaster, earthquakes are important threats that continuously effect humans and cause major destruction in certain regions. Turkey is located on the Himalayan-Alpine Seismic Belt, which is one of the geologically most active seismic regions on the world. Therefore, Turkey has to learn to live with the reality of earthquake and take all necessary measures. The Earthquake Regulations have been updated and was entered into force in 2007 to minimize structural defects in buildings in case of earthquakes, following the 17/08/1999 Kocaeli and Gölcük earthquakes, where thousands of lives were lost in Turkey, which had experienced severe earthquakes throughout history. The purpose of this study is to inspect whether necessary measures have been taken in buildings constructed after the earthquake in the province of Kocaeli, which experienced a severe earthquake in recent history and is located on a 1st Degree seismic region. In this regard, similar studies performed in the provinces of Ankara, Trabzon, Balıkesir and Yalova have been examined and building forms used in these studies have been revised. The forms have been filled with project and construction defects of 40 randomly selected buildings that have obtained license in 2015 in Kocaeli. The study consists of 5 sections; In the first section, the purpose and scope of the study has been specified and similar studies have been described. In the second section, definition and parameters of Earthquake have been described and the seismicity of the Kocaeli province and the loss of lives and damages in the 1999 earthquake have been described. In the third section, inconsistencies between the two regulations taken as basis (DBYBHY 2007 and TS 500) and recommendations have been discussed. In the fourth section, materials in the building forms, limit values in the regulations and error rate percentages have been specified. Finally, in the fifth section, comparisons have been made between the results and previous studies and manufacturing error report has been created for Turkey in general. As a result, it has been understood that the importance of earthquake has been forgotten in Kocaeli, which has experienced a severe earthquake very recently, and it has been observed that although certain progress has been achieved in project defects, manufacturing defects continued both in terms of labor and material quality.