摘要
随着提篮拱桥跨径的增加,其空间稳定性问题愈发突出,为对大跨径提篮拱桥稳定性以及各稳定性影响因素进行分析,可采用线性屈曲和非线性屈曲2种方法。重庆朝阳复建桥为主跨274 m的中承式钢箱提篮拱桥,通过建立空间有限元模型对结构线弹性稳定及几何非线性稳定进行分析表明:考虑几何非线性因素后结构的1阶稳定系数显著减小,几何非线性对结构稳定性影响显著。对影响结构整体稳定性的因素进行计算分析表明:拱肋内倾角变化对稳定性影响较大,提篮拱内倾角增大,结构的1阶稳定系数增加,但过大的内倾角将导致拱肋扭转失稳;随着矢跨比(宽跨比)的增加,结构的1阶稳定系数增大(减小);横撑、吊杆布置形式对结构稳定性影响较小。
With the increase of span length of basket handle arch bridge,the problem of spatial stability of the bridge becomes even more prominent.For analysis of the stability and the factors having influence on the stability of long span basket handle arch bridge,two methods of the linear buckling analysis and nonlinear buckling analysis may be used.The Chaoyang Rebuilt Bridge in Chongqing is a half-through steel box basket handle arch bridge with a main span 274 m.The linear elastic stability and geometric nonlinear stability of the structure are analyzed,using the spatial finite element models.The results of the analysis show that as the geometric nonlinear factors are taken into account,the 1st order stability coefficient of the structure apparently decreases and the influence of the geometric nonlinearity on the stability of the structure is apparent.The factors having influence on the global stability of the structure are also calculated and analyzed.The results of the calculation show that the influence of variations of the leaning angle of arch rib on the stability is great.As the leaning angle of the basket handle arch increases,the 1st order stability coefficient increases,however,the too big leaning angle will result in the torsional instability of the rib and as the rise-to-span ratio(width-to-span ratio) increases,the 1st order stability coefficient increases(decreases).The influence of the arrangement ways of lateral bracings and hangers on the stability of the structure is little.
出处
《桥梁建设》
EI
CSCD
北大核心
2011年第1期43-47,共5页
Bridge Construction
关键词
提篮拱桥
稳定性
有限元法
分析
basket handle arch bridge
stability
finite element method
analysis