Akademik Veri Yönetim Sistemi
JOURNAL OF MATERIALS IN CIVIL ENGINEERING, cilt.22, sa.12, ss.1252-1259, 2010 (SCI-Expanded)
High-strength concrete (HSC) has undergone many developments based on the studies of influence of cement type and cement dosages, type and proportions of mineral admixtures, type of superplasticizer, and the mineralogical composition of coarse aggregates. Most studies were carried out using natural sand. In practice, lightweight aggregates from various sources are frequently used in concrete. In the study, concrete mixtures with varying expanded perlite aggregate (EPA) ratios were subjected to dry and wet curing conditions. The variables for the mixtures were 0, 7.5, 15, 22.5, and 30% EPA ratios, in replacement of fine aggregate, in dry and wet curing conditions. The 28-day compressive strengths varied from 40 to 57 and 54 to 81 MPa for dry and wet curing conditions, respectively. The research results show that both EPA ratios and dry curing condition induced the reductions in compressive strength. The reductions due to the dry curing condition were 30, 33, 35, 40, and 26% for 0, 7.5, 15, 22.5, and 30% EPA ratios, respectively. EPA ratios of 0, 7.5, 15, 22.5, and 30% also reduced compressive strengths of 11, 12, 17, and 33% for wet cured samples. The results also show for the mixtures developed in the study that up to a total EPA content of 30% is able to provide HSC for wet curing condition and only 7.5% EPA is also adequate to achieve the HSC threshold, 50 MPa, in dry curing condition. In addition, ultrasound pulse velocity (UPV), thermal conductivity, and oven dry density of samples at both wet and dry curing conditions were determined, and relationship between thermal conductivity and oven dry density, compressive strength, and UPV were exponential for both wet and dry curing conditions.