克服大跨PC连续刚构桥后期下挠设计措施

Overcoming post-downwarping of long span PC continuous rigid frame girder by design measures

对比分析几座大跨径预应力连续刚构桥后期下挠过度引起梁体开裂的主要设计参数,阐述了引起后期下挠的主要原因.为提高箱梁持久抗剪承载力,提出构造措施上可供参考的设计参数,并提出克服箱梁后期持续下挠的具体措施,有效地保障梁体处于健康状态.

Comparing with the design parameters of several long span prestressed concrete continuous rigid frame girders, which have excessive downwarping caused by girder cracking, the main reasons of causing girder downwarping are presented. In order to improve the permanent shear carrying capacity of box girder, desigu parameters of improving structural measures are proposed. Specific measures, which can overcome the continual post-downwarpings of box girders, are presented. They can also guarantee girders in health states effectively.