An experimental investigation on mechanical characteristics of steel-fiber-reinforced volcanic concrete

Abstract

Raw materials of concrete are one of the main pollution resources. Sustainable concrete is one of the significant solutions that can be used to reduce carbon emission. This study aims to use volcanic ash (VA) as a supplementary cementitious material (SCM) for producing sustainable concrete. The effects of VA on the properties of steel fiber reinforced concrete (SFRC) are evaluated. The fresh and hardened concrete's characteristics of steel fiber volcanic ash concrete (SFVC) is presented and assessed. Slump test, compressive strength, splitting tensile tests, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and Fourier transform infrared (FTIR) spectrophotometry are used to investigate the effect of VA concrete performance. Five groups of SFVC were prepared using sixteen different mixes; 0 %, 2.5 %, 5.0 %, and 7.5 % of VA were used as a partial replacement of cement with 0, 0.5,1.0 %, and 1.5 % of steel fiber (SF). The findings demonstrated that concrete sustainability could be improved by employing VA as a partial replacement for cement, resulting in improved mechanical performance with a slight reduction in workability. The optimum mechanical and microstructure properties of SFVC were achieved with the incorporation of 5 % VA instead of cement with 1 % steel fiber, at age 28 days. The increase in compressive strength and tensile strength up to 25 % and 31 %, respectively. The employing of VA as a SCMs material resulted in better ITZ between aggregate and cement mortar and exhibited a dense surface with less pores compared to control mix.