Utilizing rice husk ash as cement replacement in pervious concrete: A review

The disposal of rice husk ash (RHA) presents environmental challenges, yet its high silica content makes it a promising partial cement replacement in pervious concrete. While previous studies have explored RHA's role in conventional concrete, comprehensive research on its effects in pervious concrete remains limited. This review systematically analyzes more than 100 peer-reviewed studies published in the last two decades, using predefined screening criteria focused on RHA dosage, processing methods, and mix design strategies. The findings indicate that incorporating 5–10 % RHA enhances compressive strength by up to 29 % and improves abrasion resistance while maintaining permeability. However, excessive replacement levels (above 15 %) reduce porosity and compromise drainage capacity. By identifying research gaps in mix optimization and long-term durability assessment, this study provides valuable insights for advancing sustainable and high-performance pervious concrete.