Properties of pervious concrete made from steel slag and magnesium phosphate cement

Abstract

Abstract The new pervious concrete (PC) were prepared using magnesium phosphate cement (MPC) as binding and waste steel slag as coarse aggregate. A series of laboratory experiments were carried out to study the influence of aggregate size and molding method on the compressive strength, flexural strength, porosity and water permeability coefficient of magnesium phosphate cement steel slag pervious concrete (MSPC). Experimental results showed that the influence of aggregate size on compressive strength is different when different molding methods were adopted. Through comparative analysis, the MSPC with medium particle size formed by vibration molding had the highest compressive strength, and the maximum can reach 41.5 MPa. Based on the excellent bonding strength of MPC, the MSPC has better flexural strength than traditional PC, and the maximum 28-day flexural strength can reach 8.0 MPa. The porosity increases with the increase of aggregate size, and which is in the range of 23.8–26.5% for all the MSPC mixtures. Similarly, the water permeability coefficient of MSPC increases as the increase of aggregate size, and with the range from 5.85 to 7.10 mm/s. The 28-day bend-press ratio of MSPC is close to 1/5. Unlike the traditional PC, the mechanical strength of MSPC increased first and then decreased with the porosity, while regardless of aggregate size and molding method, the water permeability coefficient increased linearly with the porosity. The test results indicate that the MSPC made of steel slag aggregates and MPC is a very promising eco-friendly PC.