预应力混凝土悬浇箱梁裂缝问题的探讨

随着悬浇预应力箱梁结构桥梁在交通建设项目中的普及,一些结构由于裂缝的出现,影响到桥梁的进一步应用。本文以沈彰高速公路大转弯桥、宁波市象山港大桥接线工程白墩港大桥两座典型桥梁为实际案例,通过对发生病害结构桥梁裂缝成因的理论及计算分析,推测出导致悬浇预应力箱梁结构形成裂缝的成因,提出设计过程中,通过优化预应力结构配束,增加横向钢筋加大抗剪作用等措施,减少施工期间及运营阶段外部因素对结构的不良影响,防止类似结构病害的发生。

Discussion on Prestressed Suspension Casting Box Girder Structure

With the widely use of prestressed box girder bridge structure with suspension casting popularization in the transportation construction, some structure due to the occurrence of cracks, affect the use of bridge in further. This article takes two typical bridges for practical cases which are Shenzhang highway bridge, between Baidun harbour bridge and Xiangshan harbour bridge connecting. Through theory and calculation analysis of root cause of structure bridge seam, it infers the cause of cracks which leads to the formation of prestressed suspension casting box girder structure. By optimizing the structure of prestressed tendon, reinforcing transverse rebar , increasing shear effect and other measures, it reduce the bad influence of external factors on the structure during the period of construction and operation stages, and prevent the happening of the similar structure disease.