Usability of coated aggregates in lightweight concrete production

Today, concrete is a widely used building material, and aggregates constitute 60-75% of the total volume in concrete production. One of the ways to produce lightweight concrete is to prefer lightweight aggregates in concrete production. In this way, natural or artificial lightweight aggregates are preferred in concretes aiming at low density and thermal insulation. Although our country has great potential, especially regarding pumice resources, the desired level has not been reached today in the production and usage of lightweight concrete. The essential features of natural lightweight aggregates used in the production of lightweight concrete are that their internal structures are highly porous and have a structure that can provide sufficient adherence with cement paste. In this study, the pumice aggregate belonging to the Kayseri-Talas region was coated with cement paste having four different water/binder ratios. The coated aggregates' basic physical and mechanical properties were examined, and they were used to produce structural lightweight concretes. Compressive strength, tensile strength, flexural strength, and modulus of elasticity tests were carried out on lightweight carrier concrete including coated and uncoated pumice aggregates. According to the test results, it was determined that there were significant improvements and increases in all values of the lightweight concrete produced using coated pumice aggregates. Thus, it has been determined that pumice aggregates coated with cement paste can be used in the production of structural lightweight concrete.