朝阳市东大桥钢管混凝土拱桥设计

Design of CFST East Chaoyang Arch Bridge

朝阳市东大桥主桥采用中承式钢管混凝土系杆拱桥(30m+120m+30m)。详细论述该主桥的总体设计、构造特点、内力计算和结构设计。内力分析及结构设计时,钢管混凝土的力学参数(刚度、强度)取值考虑钢管与混凝土之间的紧箍力的影响,按照钢管混凝土统一理论计算。考虑到该种结构存在车桥振动较大的问题,在结构分析中尤其重视了动力特性的计算,并从结构设计上采用加大桥面系刚度和拱肋之间的横撑刚度等措施来改善桥梁的动力特性,同时对拱桥的稳定计算进行了较为详细的讨论。最后给出了此类结构设计中应注意的问题和建议。

The main bridge of East Chaoyang bridge is halfthrough concretefilled steel tube arch bridge(30m+120m+30m).The general design,construction features and the analysis and calculation of the internal force are presented in detail.Mechanics character of CFST such as stiffness and strength used in the structure analysis is calculated based on CFST uniform theory which considers the interplay between steel tube and concrete.This type bridge has a common problem of prominent vibration under heavy load traffic condition.Therefore,two methods are used to improve the dynamic character during the structure design of East Chaoyang bridge.One is to increase the stiffness of the bridge deck system,the other is to heighten the link stiffness between two arches.The stability analysis of the arch bridge is also discussed in detail.Some issues and advices merit attention during the design of CFST arch bridge are presented.