Evaluation of pervious geopolymer concrete pavements performance for effective stormwater infiltration and water purification using Taguchi method

Atmospheric and industrial pollutants pose environmental concerns, especially when in contact with surface water, leading to contamination of the limited water supply. Pervious geopolymer concrete (PGC) is a promising approach to mitigate the above environmental concern due to its hydraulic permeation capabilities. Its porous nature helps absorb harmful pollutants and heavy metals in the water, thus purifying it for usage. The main objective of this paper is to evaluate the effect of different mix design parameters on the hydraulic performance of a PGC using the Taguchi method for effective water purification and stormwater infiltration. Accordingly, nine PGC mixtures were developed while accounting for four mix design factors at three distinct levels each. These factors included the binder dosage, dune sand inclusion, alkaline solution-to-binder ratio (S/B), and sodium hydroxide solution molarity. The precursor binding materials consisted of a 1:3 mix of fly ash (FA) and ground granulated blast furnace slag (GGBS). The optimum mixture having superior hydraulic performance was obtained by computing the signal-to-noise (S/N) ratio. The experimental test results revealed that the optimum permeability response of 12 mm/s was attained for PGC mix proportioned with 400 kg/m³, 0%, 0.55, and 8 M of binder dosage, dune sand inclusion, S/B, NH molarity, respectively. Experimental research findings serve to optimize the fabrication of PGC with enhanced hydraulic performance while minimizing the number of experiments. Such a construction material would allow for effective stormwater infiltration and resolve the challenge of stormwater runoff.