SORPTIVITY AND CHLORIDE PENETRABILITY EVALUATION OF CONCRETE INCORPORATING FLY ASH AND SILICA FUME

Abstract

Diffusion is one of the the main mechanisms of fluid ingress into the concrete. However, in partially saturated
concrete, the fluid will mainly be absorbed by the capillary suction mechanism, which associates with the sorptivity properties
of the concrete. This paper presents the results of an experimental program to investigate the influence of Portland cement
substitution with Silica Fume (SF) and Type F Fly Ash (FA) on the rate of absorption, which also known as sorptivity, and
chloride penetration of concrete. The sorptivity of the concrete was evaluated according to ASTM 1585, while the chloride
penetration was evaluated according to ASTM C 1202. By substituting part of cement with FA and SF, it was found that the
sorptivity of concrete is reduced. Furthermore, all type of concrete with supplementary material, including CFA, CSF and
CSM, is confirmed to enhance the ability of concrete to resist chloride penetration compared yo normal concrete (NC).