Abstract: This paper is based on earlier study report and field survey , relying on the World Bank (WB)Item of Chongqing City “Sewage Exluding Conduit Concrete' s Breakage Mechanism and High Strenth , Anti-erosion Concrete Material Study” , using some theory concening damage mechanics to analyze the reasonsfor the concrete box-culvert' s cracking .To damage mechanics being applied in solving engineering practice problem , this topic is a adventurous attempt .And this paper makes out aintroductiory estimate of damage area .Furthermore , it analyzes the cracking reason objectively and rationally of the concrete box-culvert by damage mechanics in Chongqing City .It is a powerful demonstration to the earlier research conchusion

Key words: buried concrete box-culvert , crack , damage analysis

摘要： 笔者基于对箱涵开裂的宏观力学分析，运用损伤力学的理论论证了箱涵开裂的原因，推得了箱涵顶板所能 承爱的极限荷载为31.17kN·m，为实际荷载的30%左右，初步估计砼箱涵的损伤区，极限深度1.56cm。换言之， 从损伤力学的观点可见，箱涵开裂是必然的

关键词: 沟埋式砼箱涵, 开裂, 损伤分析