Influence of Feldspars on the Burning of cement Clinker and on the Strength of Cement Mortar

Three series of cement were prepared from different raw materials, anorthite, leucite and albite glass, respectively, with some additional CaO and SiO_2 to compose HM=2.2 and SM=5.0. Cement obtained from albite series makes the strength of mortar weak greatly, while no appreciable decrease is observed for the one from leucite series, when compared with the cement from anorthite series. Burning process of raw materials in the temperature between 1000 and 1600℃ was also studied by means of free-lime analysis and quantitative X-ray method.