Experimental investigation of the effect of cold joint on strength and durability of concrete

Abstract

This study investigated the efects of cold joints on the strength and some durability properties of concrete. In the frst part of the study, fresh concrete was poured into molds flling them half in order to create a horizontal cold joint and after 0, 60, 120 and 180 min additional concrete was poured to top of the molds. The specimens were subjected to compressive, fexural, splitting tensile and concrete–steel rebar pullout testing. In the second part of the study, two types of concrete were prepared to carry out durability experiments. Concrete specimens with and without cold joints were subjected to drying–wetting, freezing–thawing and high temperatures (300, 600 and 900 °C) and subsequently tested for weight losses and splitting tensile strengths. It was found that strength losses due to drying–wetting and freezing–thawing of specimens with cold joints were higher than those of the specimens without cold joints. Strength losses of concretes after high temperatures showed similar results in both types of concrete.