Abstract
Portland cement clinker minerals (C3S=alite, C2S=belite, C3A, C4AF; C=CaO, S=SiO2, A=Al2O3, F=Fe2O3) have engaged interests of some mineralogists and their crystal structure analyses are nearly finished. I hope many mineralogists to have interests about the problems on concrete, awaiting analytical solution. They are the expansive action of sulphate waters, the alkali-aggregate reaction, the destructive of high-alumina cement at long ages, the cabonation from concrete surface and the non explosive demolishing agent made from lime.
