Water sorptivity and pore structure of wood–cementitious composites

Abstract

This article was carried out to evaluate the effects of non-sorptive macroporous inclusions, i.e. wood aggregates on the water sorptivity of lightweight concrete prepared from clay, cement and wood aggregates. A series of seven mixtures of wood composites with various mass fractions of wood aggregates (ranging from 10% to 40% by weight of dry clay + wood aggregates) added to a clay–cement mixture were used in this investigation. The mercury intrusion porosimetry (MIP) has been used to reflect the effect of wood aggregates on the pore size distribution. The water sorptivity of various mixtures was measured. It is shown that the addition of macroporous wood aggregates considerably reduces the capillary absorption inside the material and the cumulative water absorption (per unit area of the inflow surface) increases as the square root of the elapsed time. Tests results also show that the normalised sorptivity decreases with an increase in macroporous wood aggregates. It is also found that the macroporous non-sorptive particles considerably reduce the sorptivity of composite.