EVOLUTION OF THE PORE STRUCTURE OF A SLAG CEMENT MORTAR COMPARED WITH THAT OF PORTLAND CEMENT MORTARS

The evolution of pore structure of a slag cement mortar (clk) is studied in comparison with portland cement mortars (cpa, cpj). Pore characteristics such as total porosity, pore-size distribution, surface area, and particularly volume of larger pores (radius r is greater than 500 angstrom) are determined. It is shown that the decrease of total porosity of the mortars, with progress of hydration, appears essentially by the reduction of larger pores volume, whereas the volume of smaller pores (37 angstrom -500 angstrom) remains partially constant. This diminution of larger pores volume is more important for the slag cement mortars than for the portland cement mortars. At equal total porosities larger pores volume, or hydraulic radius of slag cement mortars is smaller than that of portland cement mortars. (Author/TRRL)