Abstract
5 portland cements with silica modulus 3.0, iron modulus 1.55 and hydraulic moduli varying from 1.9 to 2.3, and 10 high-lime portland cements with hydraulic modulus 2.3, silica moduli and iron moduli varying from 2.4 to 5.3 and from 0.6 to 4.7 respectively were prepared from commercial raw materials. The relations between the firing temperatures and the contents of free lime as well as those between the chemical compositions of the cements and their smallpiece compressive strengths were sought.
When hydraulic modulus was constant, the cement richest in alumina matured at the lowest temperature and that richest in silica matured at the highest temperature, that richest in ferric oxide being intermediate.
The cements rich in alumina were strongest and those rich in ferric oxide came next while those rich in silica were weakest.
