Mechanical Properties of Concrete Containing Ferronickel Slag as Fine Aggregate Substitute Using Digital Image Correlation Analysis

This study aimed to analyze the mechanical, displacement, and strain properties of concrete with Ferronickel Slag (FNS) fine aggregate substitute (0%, 50%, and 100%, by mass, later called FNS-0, FNS-50, and FNS-100, respectively) experimentally using the Digital Image Correlation (DIC) method and the Ultrasonic Pulse Velocity (UPV) test. The FNS used in this study is a by-product that came from a Ferronickel smelter in Indonesia coupled with manufactured sand (M-sand) as the fine aggregate control. A D10 x 20 cm(3) cylinder and 15 x 15 x 15 cm(3) cube specimens were used to analyze the density, compressive strength, and UPV. Additionally, the cube specimens were tested using the DIC method to analyze the displacement and strain properties. The test results show the highest compressive strength was obtained by FNS-50, followed by FNS-100 and FNS-50. The highest pulse velocity was obtained by FNS-100, followed by FNS-50 and FNS-0. The load-displacement response and strain behavior indicate the specimen that had the most load resistance was FNS-50, followed by FNS-100 and FNS-0. Poisson's ratio obtained using DIC and strain gauges showed consistent results where FNS-0 had the highest values, followed by FNS-50 and FNS-100. Overall, concrete with FNS substitute showed higher density, compressive strength, pulse velocity, and stiffness, as well as lower Poisson's ratio compared to control concrete (FNS-0).