Published Paper Details:

In this study, porous concrete mixes with varying proportions of aggregate, cement, and fly ash were prepared to identify the mix design that provides improved compressive strength. The research focuses on evaluating the effect of fly ash on both the compressive strength and permeability of pervious concrete. Materials used in this investigation were selected based on a detailed literature review and recommendations from local sources. Unconfined compressive strength tests were conducted on porous concrete specimens incorporating fly ash at 0%, 10%, 20%, and 30% replacement levels by weight of total cementitious materials. In addition, infiltration rate tests were performed to assess permeability. The outcomes of this study contribute to understanding how fly ash influences the mechanical and hydraulic performance of porous concrete. The results indicated the porous concrete containing 20% fly ash can achieve compressive strength greater than 15 N/mm2, and a compressive strength 14.43 N/mm2 with a infiltration rate of 0.651 cm/sec. The porous concrete with 30% fly ash had a compressive strength of 8.84 N/mm2 and the infiltration rate of 0.626 cm/sec. The failure surfaces of specimens with 20% fly ash developed through the coarse aggregates, indicating the high strength of cement bonds. The failure of specimens containing 30% fly ash was observed to be along the coarse aggregate's surfaces, indicating a lower strength of the paste. Although it was expected for porous concrete with 30% fly ash to reach a higher compressive strength at lower void content, the failure mode indicated that it may not reach the value as high as that of porous concrete with 20% fly ash.