A large amount of concrete is used in architectural engineering. The abandon concrete is about 34% of total waste materials from pulled down old buildings. It pollutes environment and is wasteful of resource.

• 在建筑工程中,混凝土的用量最大,从旧建筑物拆除的废料中,废弃混凝土约占34%25,给环境带来污染,又造成资源的浪费。