Fundamental Properties of Steam-Cured Cementitious Composites Incorporating Fine Volcanic Glass Powder

This study explores the use of volcanic glass powder (VG) derived from Shirasu volcanic deposits as a substitute for silica fume (SF) in producing high-strength precast concrete piles with a compressive strength of 123 MPa. Initially, mortar specimens with varying VG replacement ratios and curing temperatures were prepared to assess their compressive strength. After identifying the optimal mix ratios and curing conditions for high-strength mortars, concrete specimens incorporating VG were produced. Subsequent testing revealed that a VG replacement ratio of 20% by cement volume and a curing temperature of 70 °C were optimal for achieving the target compressive strength. Although the Young’s modulus of VG-incorporated concrete was slightly lower than that of pure cement and SF concrete, its performance remained satisfactory. These findings suggest that VG is a viable alternative to SF in high-strength concrete applications, providing a sustainable method to enhance concrete properties using locally available volcanic deposits.