Abstract: Promoting the utilization of glutenite manufactured sand in concrete is of significant importance. In this study, river sand and granite manufactured sand were used as references. Digital image processing (DIP), laser scanning microscopy (LSM), and the aggregate image testing system (AIMS) were employed to systematically characterize the grain shape of the glutenite manufactured sand. The influence of grain shape parameters on the workability and mechanical properties of C30 concrete was investigated. Furthermore, scanning electron microscopy and mercury intrusion method were used to elucidate the mechanisms of grain shape of manufactured sand on hydration products and pore structure of concrete. The results show that the river sand concrete with the smallest roundness exhibit the best workability, while the granite manufactured sand concrete with the largest roughness and angularity exhibits the optimal mechanical properties. The roundness, angularity and roughness of the glutenite manufactured sand are between river sand and granite manufactured sand. Glutenite manufactured sand concrete exhibits lower porosity and achieves 28 d compressive strength of 43.5 MPa, flexural strength of 5.7 MPa, and splitting tensile strength of 3.66 MPa. The glutenite manufactured sand can not only meet the performance requirements of C30 concrete, but also provide a feasible new scheme for the resource utilization of waste rock produced in the process of highway excavation.

Key words: glutenite manufactured sand, roundness, roughness, angularity, workability, mechanical property, microstructure