Recyclable Potential of Rice Husk Ash as Partial Replacement of Cement for Rigid Pavement
DOI:
https://doi.org/10.5281/zenodo.15662381Keywords:
Rice, Rigid Pavement, Rice husk Ash, Cement, concrete mechanical propertiesAbstract
Significant environmental impact caused by the high CO2 emissions during cement production has placed a climate change burden on the construction industry being the major consumer of cement. This has led to the exploration of alternative materials, such as Rice Husk Ash (RHA), a by-product of rice milling with high silica content, as a partial substitute for cement in concrete. Nigeria has been experiencing rapid urbanization and extensive road construction. This Study investigated the use of RHA in rigid pavement construction, evaluating its effects on workability, compressive strength, flexural strength, and splitting Tensile strength with 10%, 15%, 20%, 25%, and 30% replacements. The slump test revealed that as RHA content increased, workability decreased. Furthermore, 10% replacement of cement with RHA achieved the highest performance, with a 28-day compressive strength of 32.089 MPa, surpassing the design target of 30 MPa. Flexural strength at this level also met the required minimum of 3.18 N/mm². However, higher replacement levels (20–30%) resulted in significant reductions in strength which indicates diminished structural reliability. Although the peak splitting tensile strength of 2.38 MPa was achieved at 15% RHA replacement, all mixes except for the 30% replacement remained within the 2–5 MPa range recommended for rigid pavement applications. Overall, RHA-modified concrete with up to 10% replacement demonstrates potential for rigid pavement use in road construction