Portland cement

The invention relates to the technical field of building materials, in particular to Portland cement. The Portland cement comprises, by weight, 85-95 parts of Portland cement clinker, 4-8 parts of gypsum, 1-2 parts of coagulation accelerator and 2-3 parts of water reducer. By adding the coagulation accelerator and the water reducer, early strength of the cement is improved, and especially strengthafter three or four hours. Demolding time of the cement is shortened, and building production efficiency is improved. By adding sodium hydroxide into the cement clinker to bring in a proper amount ofalkali content, early hydration speed of the clinker is accelerated, and the early strength of the cement is improved further; by adding ferric oxide into the cement clinker to bring in a small amount of iron ions, calcining temperature of the clinker is enabled to be low, and heat consumption of the clinker during calcining is lowered. 本发明涉及建筑材料技术领域，具体涉及种硅酸盐水泥。包括如下重量份的成分：硅酸盐水泥熟料：85-95份；石膏：4-8份；促凝剂：1-2份；减水剂：2-3份。本发明通过加入促凝