The effect of adding different pozzolans on mechanical properties and water absorption of Pervious Concrete Pavement

Pervious concrete is a special type of concrete comprised of cement, water, coarse aggregate, little or no sand which is sometimes mixed with the additives. The uniformly graded coarse aggregates in combination with low water content (i.e., water-to-cement ratios ranging from 0.25 to 0.35) were used to produce a concrete mixture whose pore content ranges from 11% to 35%. In this paper, performance of pervious concrete containing silica fume, zeolite, fly ash and granulated blast furnace slag (10% and 20% of cement weight) was investigated at the ages of 7 and 28 days. To this end, The compressive and tensile as well as water absorption tests were conducted on cubic and cylinderical specimens whise dimensions are 10 and 10×20 cm, respectively. In order to provide the required materials, the fine-grained gravel extracted from the Hamesh Bar mine Located in Semnan Province, was used. The results imply that compared to the other materials, application of silica fume and granulated blast furnace slag leave the greatest effects on the concrete performance in a way that averagely, the compressive and tensile strength were improved nearly 1.6 and 3 times in comparison with the control specimen (i.e. reference specimen). Moreover, the water absorption was reduced following addition of various pozzolanic materials excpet silica fume such that according to CEB-FIP Standard, they are classified as average and good concretes.