Effect of ceramsite structure on microstructure of interfacial zone and durability of combined aggregate concrete

Abstract

Structure characteristics of three kinds of ceramsite with different water absorption and the influence on microstructure of interfacial zone as well as performance of chloride permeability and frost resistance of combined aggregate concrete were investigated. The results show that, dense shell and closed internal pore have sharp effects on lowering water absorption of ceramsite. However, the ceramsite with high water absorption has obvious effect on the densification of interfacial paste which would develop a structure with lower porosity, finer aperture and higher microhardness. Furthermore, the impermeability and frost-resistance of concrete can be improved due to the effect of water absorption and releasing by ceramsite with higher water absorption.

Keywords

ceramsite / combined aggregate concrete / chloride permeability / frost resistance / pore structure / microhardness

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