A NEW FACTOR IN ABNORMAL SETTING OF PORTLAND CEMENT

TO MEASURE AMOUNTS OF HYDRATION PRODUCTS OF PORTLAND CEMENT PASTES AFTER 1/4 TO 15 MINUTES OF CURING, DTA AT HIGH SENSITIVITY WAS APPLIED. RESULTS ON CEMENT AND CLINKER, WITH AND WITHOUT AERATION IN PRESENCE AND ABSENCE OF CARBON DIOXIDE, REVEALED AMOUNTS OF HYDRATION PRODUCTS /DUE TO REACTIONS WITH LIQUID WATER BETWEEN 3 AND 15 MINUTES/ WERE MINIMAL AND CONSIDERED NOT A CAUSE OF ABNORMAL SET. ANALYSIS OF THE AQUEOUS PHASE SUPPORTED THIS OBSERVATION. IT IS SPECULATED THAT THIXOTROPY MAY BE A FACTOR IN ABNORMAL SET OF PORTLAND CEMENT. /AUTHOR/