Investigation of adherence of reinforced concrete members produced in cold environment

The aim of this study is to examine the reinforcement adherence of reinforced concrete elements exposed to cold air in fresh state. The Belgian hinged beam test method was used to determine reinforcement adherence strength. Within the scope of the study, the adherence strengths were determined in C25 / 30 concrete strength grade, S420 steel grade and in Ø8, Ø10 and Ø12 reinforcement diameters, Two different clamping lengths were used to examine the change in adherence strength of the reinforcements to be used in the determination of adherence. The clamping lengths were prepared as 10Ø and 20Ø according to the reinforcement diameter. In order to determine the effect of ambient conditions on the reinforcement adherence of beams prepared for the Belgian Hinged Beam test setup, fresh beams samples were exposed to normal conditions, and the temperatures 0°C, -5°C and -10°C for 2 days. The beams were exposed to normal conditions and cold air for 2 days in fresh condition and cured until the 7th and 28th day. The beam samples, whose curation process was completed, were subjected to adherence test. In addition, in order to see the change in the concrete compressive strength depending on the cold weather conditions of the concrete used in the preparation of the beam samples, compressive strength test was carried out on the cube samples prepared in the size of 15x15x15 cm. As a result, it was seen that the beam samples exposed to normal conditions had the greatest adherence stress and the adherence stress decreased due to the decrease in the temperature value under which the concrete was exposed in its fresh state. Furthermore, with the decrease in the temperature value of the concrete strengths, more than 30% loss in compressive strength was determined.