【摘要】 随着钢拱桥跨径的不断增大,钢拱桥在静风荷载作用下的施工稳定性问题已引起了人们的广泛重视.以上海在建的主跨550 m的中承式钢拱桥为例,采用几何和材料非线性分析法详细分析了大跨度钢拱桥在2个不同施工阶段下的静风稳定性.结果表明,拱肋最初合龙状态是施工过程中最不利的状态.最后,详细探讨了施工过程中拱桥结构静风失稳机理.更多还原

【Abstract】 The wind-induced instability of long-span steel arch bridges is a serious engineering concern, particularly during construction. Using Lupu Bridge with a main span length of 550 m as an example, this paper investigates the wind-induced load capacity of a long span steel arch bridge under two construction stages, namely construction stages Ⅰ and Ⅱ . Construction stage Ⅰ is a maximum-cantilevered system before the closure of main arch ribs. Construction stage Ⅱ is a system that the other parts of the bridge have been completed except the stiffening girder of the main span. Three components of wind loads acting on both steel girder and arch ribs are considered in the analysis. The results show that the arch bridge at construction stage Ⅱ is more susceptible to the wind-induced instability than that at construction stage Ⅰ .Finally,the wind-induced failure mechanism of long-span steel arch bridges under construction is discussed.更多还原