Investigation of earthquake behavior of unreinforced masonry buildings having different opening sizes: Experimental studies and numerical simulation

In this study, three calcium silicate unreinforced masonry buildings were investigated via experimental studies and numerical simulation in order to determine their earthquake behavior. For building behavior, full-scale (1:1) masonry buildings, having different opening sizes, were subjected to cyclic loading. In each cycle, load and displacement values were recorded by computer setup and the occurred damage was marked on the building. It was observed that behavior of the building was linear until approximately 77% of maximum load and that there was no damage except for a few hairline cracks. Subsequent to this load level, change in the displacement value moved away from being linear and nonlinear behavior was observed at about 88% of the maximum load level. Hereafter, characteristic damage formation began and crack sizes increased. Torsional effect was also observed because of the stiffness difference due to the opening size in the walls. After maximum load level, it was determined that the building dissipated energy with opened-closed cracks and reached the collapsing limit at nearly a 1% story drift ratio. In the scope of numerical simulation, first masonry building was modeled with macro modeling using ANSYS software and the system was simulated by a similar load effect as the experimental study. The damage that occurred during the experimental studies was evaluated in terms of masonry building behavior and the numerical results were compared with the experimental results. The numerical simulation results were consistent with the experimental results until the maximum load level, but after this load level, the simulation results were not consistent with the experimental results

Investigation of physical and mechanical properties of mortars produced by polymer coated perlite aggregate

With its low unit weight, expanded perlite (EP) offers significant advantages in heat and sound insulation in the construction sector. However, due to its high-water absorption capacity, EP affects the physical and mechanical properties of concrete negatively. Therefore, it is aimed to reduce water absorption by coating the EP with polymer and thus to improve its mechanical and physical properties. In this study, mortar production was carried out by replacing coated and uncoated EP with CEN reference sand at 0%, 20%, 40%, 60%, and 80% respectively. The effective water/cement ratio of all produced mortar samples was determined to be 0.6. For coated and uncoated EP aggregate mortar series, unit weight, compressive strength, bending tensile strength, water absorption, ultrasonic pulse velocity (UPV), and thermal conductivity coefficient were determined. The results showed that the unit weight of the mortar samples decreased as the amount of EP increased, but their physical and mechanical properties also changed. Mortar samples with better thermal insulation properties were obtained with decreasing thermal conductivity values. The polymer coating of EP improved physical and mechanical properties. Especially in the 80% substituted EP series, the thermal conductivity decreased from 1.20 to a coefficient of 0.91 W/mK. © 202