Potential application of nano-silica in concrete pavement: A bibliographic analysis and comprehensive review

Abstract

Rapid population growth in developing countries necessitates high-performance, long-lasting pavement construction. Rigid concrete pavement, commonly used in India, to use for heavy automobile transportation and pedestrian surfaces. However, its high resource consumption, low tensile strength, and initial construction cost are drawbacks. Researchers are exploring the use of nanomaterials in pavement engineering to improve concrete's long-term durability. Nanotechnology is considered the next-generation industrial revolution due to its extraordinary characteristics at a small scale. However, the use of nanomaterials in pavement engineering is still in its early stages. Nanoparticles, which act as fillers and reinforcements in concrete mixtures, enhance the strength and durability of pavements. This is due to the C–S–H gel component of hardened concrete, which is essential for maintaining the pavement's strength and durability. The use of various nanomaterials like nano-silica, nano-CaCO₃, nano-Al₂O₃, nano-TiO₂, and nano-clay is being explored as a partial cement replacement. One of the most exciting nanomaterials, nano-silica, is widely used. The study explores the use of nano-silica as a partial replacement for cement, focusing on its impact on mechanical, durability, and microstructure characteristics of concrete pavements. The optimal percentage of nS, as well as the form of nS (powder or colloidal), to improve cement concrete pavement was investigated in this study. The study suggests that nano-silica-modified concrete pavements can withstand vehicles' dynamic and static loads and are a potential eco-friendly alternative to cementitious composites. More percentage of waste materials can be replaced by adding nS to concrete pavement. In comparison to the powdered form of nS, the colloidal form disperses evenly in the concrete matrix without forming agglomerates. According to the study, raising the nS concentration improves mechanical and durability characteristics at 3%, however, above 5% might induce material degradation.