The effect of the type of capping materails on the compressive strength of high and medium strength concrete

The factors that have effects on the compressive strength of the concrete are; geometry and size of the sample, loading rate, humidity, and temperature of the sample and the surface properties of the sample, respectively. The aim of this study is investigate the effect of capping material tyeps on the compressive strenght results of concrete cylinder specimens. In this research, medium and high strength concrete which have 4 different strenght classes were produced such as C40, C50, C60, C70 . A three hundered and thirty-six concrete cylinders specimens having dimensions of 150/300 and 100/200 mm were casted. At the end of 28 days standart curing period, the unaxial compressive strenght of capped and uncapped specimens was determined. Sulfur paste, cement paste, gypsum paste, mortar paste, sand and rubber are used as capping materials. Compressive strenght results of specimens evaluated consedering uncapped ones. Based on the results obtained from this study, sulphur mortar capping systems showed better results than others. The use of sulfur mortar caping system yield avarega compressive strenght 16.3% higher than those obtained using uncapped, irrespective strenght classes and specimens size