人类对传统人工墙体建筑材料——砖,已使用了几千年。到本世纪初,随着科学技术的进步和工业的发展,一些国家相继研制和使用了新型墙体材料。我国由五十年代中 Humans have used millstones for traditional artificial wall building materials for thousands of years. By the beginning of this century, with the advancement of science and technology and the development of industry, some countries have successively developed and used new wall materials. Our country was made of mid-fifties