The Influence of Iron Tailings Powder on the Properties on the Performances of Cement Concrete with Machine-Made Sand

Iron tailings powder (ITP) is a kind of solid waste, which pollutes the environment, without any treatment. The application of ITP in cement concrete is a good choice. In this study, the influence of ITP on the flowability, compressive strength, chloride ion permeability and the attenuation of the performance of cement concrete during freeze-thaw cycle (F-T) damage are investigated. An X-ray diffraction, an analysis of the pores and a scanning electron microscope (SEM) are obtained to analyze the mechanism of cement concrete's performance. The results show that the addition of ITP can decrease the flowability of fresh cement concrete. Cement concrete with a 7% ITP to mass ratio of the total aggregate shows the highest compressive strength and the minimum chloride ion permeability. The relative dynamic modulus of the elasticity of the specimens with 7% ITP during the F-T is the highest. The corresponding mass loss rate is the lowest. The mercury intrusion analysis results show that the pore volume of the specimens with 7% ITP is the lowest. The SEM results confirm that the specimens with 7% ITP show the densest microstructures.