梁桥恒载跨中挠度允许值[f_t]确定

Determination of Allowable Value of Constant Load Deflection [f_t] for Girder Bridge

长期以来,我国桥规对梁桥恒载跨中挠度允许值[ft]空缺;一般均用活载挠度fp=[L/600]来代替。这是造成中国PC连续梁跨中普遍下挠、底板开裂的一个重要原因。文中提出设计应控制合龙前初始挠度[f0]≤L/4 800才能确保桥梁安全。

For a long time,there is a vacancy of the deflection value [ft] for girder bridge across the rules in China,which is often replaced by deflection f p = [ L/600 ] instead.This is one of the major reasons for beam deflection and bottom cracking of Chinese PC continuous girder bridge.The paper puts forward that the design should be folded control with initial deflection [f0] no more than L/4800to ensure the safety of bridge.