新型上承式拱桥结构体系静力特性分析

Static Characteristics Analysis of New Deck Arch Bridge Structure System

随着跨径及荷载的不断增加,传统上承式拱桥结构刚度小、自振频率低的特性难以满足现代交通需求。在此背景下,介绍一种新型上承式拱桥结构,该结构在拱肋与主梁间增设刚性斜杆,形成桁架结构,实现拱结构到桁架结构的体系转换,从而减轻拱肋的负担。并以1座跨径为500m的公路上承式拱桥为例,通过有限元数值法进行强度与刚度的计算,结果表明:新型上承式拱桥的强度和刚度均优于传统上承式拱桥。

With the increasing of span diameter and load,the traditional deck arch bridge structure with small stiffness and low self-oscillation frequency is difficult to meet the modern traffic demand.In this context,a new type of deck arch bridge structure is introduced.The structure adds a rigid inclined bar between the arch rib and the main beam to form a truss structure,which realizes the system conversion from arch structure to truss structure,thereby reducing the burden of arch ribs.Taking a highway deck arch bridge with a span of 500m as an example,the strength and stiffness are calculated by finite element numerical method,and the results show that the new deck arch bridge is better than the traditional deck arch bridge in terms of both strength and stiffness.