Abstract: Crack limit values home and abroad are analyzed and compared，and then the connotation and characteristics of the allowance width of crack are pointed out respectively． It is proposed that durability crack limit should take environment， steel，stress characteristic，component styles，crack position and construction feature into consideration． The crack limit range and relationships of concrete component and pre-stressed concrete component are concluded in alternate drying-wetting， no alternate drying-wetting and corrosion environment，which provides useful reference for allowance width of crack in concrete bridge constructor based on durability．

Key words: concrete bridge, durability, allowance width of crack, environmental effect

摘要： 分析比较了国内外标准中关于混凝土构件裂缝宽度限值的规定，指出了各个标准限值的特点及其内涵，提出 桥梁混凝土构件耐久性指标裂缝宽度限值的确定应考虑环境作用、结构受力特点、构件种类、受力状态、构造特点等 因素的影响; 归纳出干湿交替、无干湿交替及腐蚀3 种环境下，钢筋混凝土及预应力混凝土构件的裂缝宽度限值的 一般范围和相互关系，为确定公路桥梁混凝土构件基于耐久性的裂缝限值提供参考。

关键词: 混凝土桥梁, 耐久性, 裂缝宽度限值, 环境作用