为了分析某普通钢筋混凝土箱梁在运营一年多后即出现严重开裂的原因,根据规范对箱梁截面设计与裂缝宽度进行了复核校验,结果满足规范设计要求,但实际最大裂缝宽度远大于规范限值。为此,利用数值模拟方法从车辆超载、荷载偏心、裂缝宽度分布等多个角度对裂缝的成因进行了分析。结果表明,超载与偏心是导致裂缝出现的主要原因,而箱梁裂缝最大宽度计算理论不完善是导致裂缝严重超标的重要原因。 In order to analyze the reason of serious cracking of a common reinforced concrete box girder more than one year after operation, the cross-section design and crack width of the box girder are checked and verified according to the code, and the results meet the standard design requirements. However, the actual maximum crack width is much larger Regulatory limits. Therefore, numerical simulation is used to analyze the causes of cracks from many aspects such as vehicle overloading, load eccentricity and crack width distribution. The results show that overloading and eccentricity are the main reasons leading to the cracks. The imperfect theoretical calculation of the maximum width of cracks in the box girder is an important reason leading to serious over - standard cracks.