Is the coefficient of permeability taken into account in mix design of pervious concrete ? Please explain mix design of pervious concrete for example for M20.

I am using auramix 350 admixture for pervious concrete. The mix proportion at higher cement content of 450 kg/m3 the lower water content was taken as 95 lt/m3 as with water 90 lt/m3 resulted in very harsh mix and couldn’t be compacted properly. The water to cement ratio ranges from 0.21 to 0.43 practically covering the wide range applicable to field practice. The void chosen for the mixes is fixed constant for all the trials at 15% in order to compare the results. Keeping in mind the twin satisfactory requirements of sufficient strength and permeability the fine aggregate content was varied from 0% to 15% in increments of 5%. The mix design method adopted is based on absolute volume concept starting with a volume of paste.