AN EXPERIMENTAL INVESTIGATION OF PERVIOUS CONCRETE WITH USE OF FLY ASH AND SILICA FUME AS ADMIXTURE

Abstract

In many developed countries, pervious concrete is becoming popular for the construction of pavements, car parks and driveways. For the effective use of pervious concrete, it is necessary to evaluate performance of this new type of concrete. The most important property of pervious concrete is its water permeability as it is measure of perviousness of the said concrete. To achieves high porosity only coarse aggregates may be used but it reduces the compressive strength of pervious concrete. So, different categories of coarse aggregates are taken to achieve the required compressive strength. Different Percentage ratio of (20-10) mm and (10-4.75) mm coarse aggregates has been used to cast pervious concrete. As the ratio of 50%-50% has given optimum permeability it has been selected for further work in pervious concrete. In this study, fly ash and silica fume has been replaced by cement from 0% to 25% and water permeability as well as compressive strength of pervious concrete has been tested. Results showed that Replacement of Fly ash from 5% to 25% shows decrement in strength from 4% to 28%. And permeability also decreased with increment of fly ash mix up to 30% than normal pervious concrete as well as in silica fume, replacement from 5% to 25% shows that with 5% replacement of cement with silica fume increased strength up to 24% higher than normal pervious concrete. But with further increment of this admixture with replaced to cement showed strength loss of 44% then normal pervious concrete