Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 52 9 2020 11 21 Laboratory Evaluation of Bond Strength Between Rebar and Concrete Containing Limestone Powder Laboratory Evaluation of Bond Strength Between Rebar and Concrete Containing Limestone Powder 2279 2288 3467 10.22060/ceej.2019.16315.6186 FA Seyed Abbas Hosseini Faculty of Technology and Mining, Yasouj University, Choram, Iran Sadegh Etedali Department of Civil Engineering, Birjand University of Technology, Birjand, Iran Journal Article 2019 05 11 The amount of adhesion between the concrete and the reinforcing bars plays a decisive role in the behavior of the RC structures, as well as their failure mode in the final extreme cases. This adhesion, known as band resistance, can be altered by changing the concrete mix. Laboratory evaluation of bond strength between rebar and concrete containing limestone powder is carried out in the present paper. For this purpose, 5, 15 and 30% of the cement of the control specimen (without limestone powder) is replaced with limestone powder and bond and compressive strength are obtained for specimens at the age of 7, 28 and 90 days. In this study, 15 cm concrete cubic and 16 mm diameter rebar are used to evaluate the bond. The water to binder ratio (w/b) is fixed at 0.4. Also, the test of pulling out the rebar is applied to calculate the bond strength between the concrete and steel reinforcement. The overall results show that the bond strength decreases with the increasing percentage of limestone in concrete, the amount of this reduction is less than 10% for a sample with 5% limestone powder, while a reduction about 40% is obtained for a sample with 5% limestone powder. The assessment of the exciting models for prediction the bond strength indicates that these models estimate a bond strength larger than those given by the experimental results. Therefore, it is necessary to provide a suitable model for estimating the bond strength of concrete containing limestone powder. The amount of adhesion between the concrete and the reinforcing bars plays a decisive role in the behavior of the RC structures, as well as their failure mode in the final extreme cases. This adhesion, known as band resistance, can be altered by changing the concrete mix. Laboratory evaluation of bond strength between rebar and concrete containing limestone powder is carried out in the present paper. For this purpose, 5, 15 and 30% of the cement of the control specimen (without limestone powder) is replaced with limestone powder and bond and compressive strength are obtained for specimens at the age of 7, 28 and 90 days. In this study, 15 cm concrete cubic and 16 mm diameter rebar are used to evaluate the bond. The water to binder ratio (w/b) is fixed at 0.4. Also, the test of pulling out the rebar is applied to calculate the bond strength between the concrete and steel reinforcement. The overall results show that the bond strength decreases with the increasing percentage of limestone in concrete, the amount of this reduction is less than 10% for a sample with 5% limestone powder, while a reduction about 40% is obtained for a sample with 5% limestone powder. The assessment of the exciting models for prediction the bond strength indicates that these models estimate a bond strength larger than those given by the experimental results. Therefore, it is necessary to provide a suitable model for estimating the bond strength of concrete containing limestone powder. https://ceej.aut.ac.ir/article_3467_2a2717956118b4d223ceca17ce3865e2.pdf