预应力钢拱加固双曲拱桥的设计分析

Analysis of the Method to Strengthen Double-arched Bridge with Prestressed Steel Arch

在我国,由于许多混凝土双曲拱桥荷载设计标准偏低和长期超载,导致其主拱应力水平过高,威胁了行车安全,急待加固。文中首次提出了预应力钢拱承托加固法,该加固方法可以在不中断交通、不影响通航净空的情况下,通过在加固钢拱内建立预压应力,达到有效降低双曲拱桥混凝土主拱的应力水平并提高其承载能力的目的。结合工程实例,文中分析预应力钢拱承托加固法的设计原理,并介绍了加固设计方法。

Because of lower design load and overloaded traffic,the problem of overstress in main arch is popular for many concrete double-arched bridges.This problem threatens the safety of bridges and vehicle.Therefore,these bridges need urgently to be strengthened.A method of strengthening concrete double-arched bridge is presented to decrease the higher stress lever in main arch with prestressed steel arch.At the same time,the traffic is not interrupted and the navigational capacity is not reduced.A successful case is also introduced with detailed analysis.