Preparation and characterization of road alkali-activated blast furnace slag paste

Alkali-activated Materials (AAM) has been applied in road engineering as an environmentally friendly material in recent years. This study prepared road alkali-activated blast furnace slag (AABFS) paste in different mixture ratios based on an orthogonal test scheme. The fluidity, setting time, mechanical strengths, and other properties were systematically evaluated to determine the optimum mixture ratio of paste. Finally, the microstructural characteristics and reaction mechanism of AABFS paste were investigated. The results showed that changes in the mass ratio of sodium hydroxide and blast furnace slag (mSH/mSL) have great influence on the performance parameters, including the fluidity, setting time, flexural strength, and compressive strength. Results at the microstructural level indicated that the structure of the AABFS paste specimen prepared at the optimum ratio is more compact and uniform, and the AABFS paste can be applied effectively in road-grouting reinforcement.