Percolation of capillary pores in hardening cement pastes

This paper presents a study of the pore structure and permeability of hardening cement pastes. Cement pastes with water/cement (w/c) ratio 0.4, 0.5 and 0.6 from 1 up to 28 days of age were tested with mercury intrusion porosimetry. In parallel, the water permeability was measured. With the help of a numerical simulation model, correlations between pore structure and permeability were found. Water permeability is related more to the pore size distribution and to the effective porosity than to the total porosity of the pastes. No depercolation of the capillary pores was evident neither in the experiments nor in the numerical simulations during the first 28 days after casting. (C) 2004 Elsevier Ltd. All rights reserved.