一、简况 现在世界上混凝土的年产量已超过50亿吨。根据国内外人们预测,下一个世纪混凝土材料仍然是土建工程中主要采用的结构材料,进入到二十一世纪时混凝土年产量可达100亿吨,非但不会被任何其他材料所淘汰,甚至会获得更迅速地发展。 众所周知,混凝土是一种多微孔非匀质材料,它的固有特点是:具有较高的抗压强 I. Brief introduction The concrete production in the world now exceeds 5 billion tons. According to predictions by people at home and abroad, the concrete materials used in civil engineering are still the main structural materials used in the next century. When the 21st century enters, the annual output of concrete can reach 10 billion tons. It will not be eliminated by any other materials, even Get more rapid development. As we all know, concrete is a kind of microporous non-homogeneous material, its inherent characteristics are: high pressure resistance