Physical and Chemical characteristics affecting the Durability of Condensed Silica Fume (CSF) Blended Cement Concrete
Alhassan, A. Yunusa & Yunus Ballim
Department of Civil Engineering, Federal Polytechnic Idah, Nigeria
School of Civil and Environmental Engineering, University of the Witwatersrand, Johannesburg, South Africa
Corresponding Author: Alhassan, A. Yunusa
ABSTRACT
The durability performance of reinforced concrete is influenced by those physical characteristics of concrete that controls the diffusion of gases and or liquid through its pores. These physical characteristics depend on the chemical composition and the microclimatic condition of the environment. In the present paper, properties of concrete made with Condensed Silica Fume (CSF) blended cement were characterized in terms of physical and chemical composition at early-age. In addition, the effects of inland exposure condition on the durability performance of the concrete were also investigated. Concrete cubes were made using various concrete mixtures of water-binder ratios (w/b) = 0.40, 0.50, 0.60, 0.75 and binder contents = 300, 350, 400, 450 kg/m3. Concrete cube of 100 mm size were cast and cured in water for 3, 7, or 28 days, then characterized at early-ages in terms of its physical and chemical properties. Companion concrete samples were exposed indoors or outdoors to undergo carbonation under natural environment. At the end of the varying exposure period, the concrete cube samples were characterized in terms of carbonation depths. The results of the concrete early-age properties and medium-term durability characterisation were analyzed. The results show that, increased knowledge of concrete materials and concrete early-age properties is vital in durability considerations for reinforced concrete structures.
Keywords: Reinforced concrete; Concrete durability; Pore structure; Pozzolans; carbonation; condensed silica fume; inland environment.
