Sulfate Resistance of Mortars Made Using Portland Cement and Blends of Portland Cement and Pozzolan or Slag

摘要

Mortar bars were made from 23 Type I, 9 Type II, 2 Type V, 15 Type IP, 5 Type IS, and blends of Type I with slag and with various pozzolans including one silica fume. The bars were stored in a 5-percent sodium sulfate solution and monitored for changes in length and in resonant frequency. The length changes of the bars indicated tht silica fume and a natural pozzolan showed impressive improvement of the blends over the use of a nonsulfate-resistant cement by itself, while blends made using slag, and other pozzolans in the amounts studied, in some cases showed only slightly improved resistance and in other cases no improvements. Keywords: Blended cements, Fundamental frequency, Length change, Mortar bar, Portland pozzolan, Sulfate resistance. (jes)