一、概述人类最初用天然树木,石块、土来建造住处,后来发现点过火的土块变得很坚硬,因而逐渐发明了烧土制品;又发现用火煅烧过的石灰石可以变成具有胶凝性质的材料,可以用来砌筑石块或烧过的土块,这就是石灰胶凝材料。在漫长的生产实践过程中,人们又发现含一定量粘土的石灰石煅烧后所得的产品具有不怕水的性质。由于天然含粘土 I. General description Humans originally built natural dwellings with natural trees, stones, and soil. Later, it was found that the overlying earth blocks became very hard. As a result, clay products were gradually invented. It was also found that limestone calcined with fire could become plastic. The condensate material can be used to build stones or burned clay blocks. This is the lime cement material. In the course of long production practices, people have found that calcined limestone containing a certain amount of clay has a property that is not afraid of water. Because of the natural clay