Mechanical properties and microstructure of artificial sand concrete based on rock-powder content

The rock-powder content in artificial sand has a significant impact on the performance of concrete. In order to investigate the influence of rock-powder content on the physical and mechanical properties of artificial sand concrete, this study summarizes the current application status and background of artificial sand. Starting from the characteristics of artificial sand, different levels of rock-powder content in artificial sand are discussed. Scanning electron microscopy (SEM) tests are conducted on artificial sand products made from stone chips in Shangqiu, Henan Province. The research findings indicate that when the rock-powder content is between 6 % and 15 %, the workability of the concrete improves, and it exhibits higher strength and a larger strength-to-cementitious ratio. However, when the rock-powder content exceeds 20 %, although the workability still improves, the strength decreases, and the strength-to-cementitious ratio becomes smaller. Under a magnification of 2000X, the SEM images show a good bonding between artificial sand and the cementitious gel C-S-H in the concrete, with no cracks at the interface of artificial sand. These results demonstrate a favorable outcome. It is expected that the research findings will provide theoretical reference for the application of artificial sand in concrete structures.