预应力混凝土箱梁由于体量较大,往往分次浇注,但是施工中容易出现裂缝。本文某40m跨径的单箱多室的简支箱梁为例,从设计施工等方面分析了其施工过程中顶板出现横向裂缝的原因及对结构承载能力的影响,并对防止此类裂缝提出了改进措施,可供类似工程借鉴。 Prestressed concrete box girders due to the larger volume, often sub-casting, but prone to cracks in the construction. In this paper, a 40m span single box multi-chamber simple box girder as an example, from the design and construction aspects of the construction process of the roof cracks occur in the horizontal and the impact on the structural carrying capacity, and to prevent such cracks proposed Improve measures for similar projects for reference.