钢管混凝土拱桥拱肋刚度设计取值分析

为了解桁式钢管混凝土拱肋弦管设计刚度对拱桥受力性能计算结果的影响,以一座钢管混凝土多肢桁式拱桥为实例,建立了有限元模型,进行了弦管截面设计刚度取值的参数分析,在对已建钢管混凝土桁式拱桥的截面构成进行调查的基础上,提出了桁式拱桥截面设计刚度取值建议,即根据不同的计算要求,混凝土截面刚度折减系数取1.0或0.4。分析结果显示,按照该建议,截面的内力计算值为实测值的1.2～1.5倍,变形计算值为实测值的1.5～1.9倍。可见,此取值建议可以保证桁式钢管混凝土拱桥的设计具有一定的安全储备。

Analysis on rib rigidity of concrete filled steel tubular arch bridge

In order to study the effect of tube rigidity on the mechanical character of truss CFST(concrete filled steel tubular)arch bridge,a true arch bridge was taken as sample,and the parameter analysis for the rigidity was carried out by using finite element model.Based on the investigation of section composition for arch rib,a suggestion was presented to calculate tube rigidity,in which the rigidity reduced factor of concrete was adopted as 1.0 or 0.4 for different calculation demands.Analysis result indicates that for internal force,the rate of calculation value to reality value is between 1.2 and 1.5,for deformation the rate is between 1.5 and 1.9.So,the suggestion can secure some safety reserve for the design of truss CFST arch bridge.4 tabs,14 figs,14 refs.