High temperature effect on concrete coated with different type of mortars

The development of technology, the increase in industrialization and growth in the population cause excessive energy use and as a result of this, it brings the risk of fire. Since the fire effect has a very important effect in terms of concrete strength, high temperature effect is one of the parameters to be considered for every structure. The effect of high temperature, which is an important parameter in concrete, can cause cracks, color changes and fragmentation in concrete. As a result of these effects, significant losses in concrete strength can be observed. Knowing the behavior of building materials against fire has an important place in taking protection measures for materials. In this study, unplastered control concrete samples and plaster mortars by using 5 groups of binder materials (Portland Composite Cement, Lime-Portland Composite Cement, Calcium Aluminate Cement, Blast Furnace Slag activated with NaOH and KOH alkali activator) for coating control concrete samples were produced. Produced samples were exposed to high temperature (100, 300, 500 and 700 °C) at three different curing times (7, 14 and 28 days). Interior concrete samples were obtained by cutting the plaster of the plastered concretes exposed to high temperatures after the fire. As a result of the study, compressive strength, ultrasonic pulse velocity (UPV), water absorption rate, weight loss rate, unit volume weight (UVW) tests and microstructure analyzes were performed on the samples. According to the results obtained, the compressive strength of the samples coated with plaster exposed to high temperature was higher than the control concrete samples that were not coated with plaster. In plaster cut samples while the samples produced using Portland Composite Cement showed the best strength in terms of compressive strength, the samples produced using Calcium Aluminate Cement had the best result in terms of weight loss rate.