Pore solution composition of calcium sulfoaluminate cement

The chemical compositions of the pore solution expressed from commercial calcium sulfoaluminate-belite cement paste at selected intervals of 1, 3, 7, 14, 30 and 60 days, cured at 20°C, have been determined. pH was measured in the range 12·8–13·1; changes in concentrations of Na, K, Ca, Al, Si, CI, Br and SO₄²⁻ were determined between 1 and 60 days of curing. The main components in the pore solution were Al and K: Na, Ca, CI, Br and SO₄²⁻ concentrations were low, and the Si concentration was below the detection limit. Potassium is slowly sorbed by the solids, and its concentration passes through a maximum at ∼3 days.