Experimental investigation of concrete strength of the personal and public structures in Bilecik province

In our country, the majority of the building stock is manufactured with reinforced concrete system. There is a similar situation in Bilecik. The use of ready-mixed concrete's strength values can be affected negatively when it used unconsciously, and without proper control. The aim of this study is to determine the in place concrete strength of structures constructed before and after 2000. For this reason 36 different public and private reinforced concrete structures were investigated with core drilling method in order to determine the physical and mechanical properties of placed concrete. In this research, 70 % of the buildings are between ages 20 and 50 years. In addition, the comparison of hand mixed and ready mixed concrete in place strength values were performed. In this study, approximately 60 % of the core specimen's strength values were found that lower than 20 MPa. Furthermore carbonation test was performed on core specimens in order to obtain the carbonation depth and corrosion risk of the reinforced concrete structures. Carbonation test results showed that the 40 % of core samples taken from the premises of the carbonation depth is greater than 40 mm and 30 % of the specimens showed no carbonation depth. According to test results; the hand mixed concrete used structures strength properties were more irregular than ready mix concrete used structures strength results. Also the water absorption test results showed that the concrete structures produced before 2000 50 % result difference was found.