外倾拱非线性行为的影响因素分析  

Analysis on influencing factors of nonlinearity behavior of outward inclined arches

作　　者：霍学晋[1] 韩立中[2] 

机构地区：[1]中铁大桥勘测设计院集团有限公司,湖北武汉430056 [2]交通运输部公路科学研究院,北京100088

出　　处：《空间结构》2015年第4期66-74,共9页Spatial Structures

基　　金：国家自然科学基金重点项目(51138007);国家科技支撑计划(2011BAJ09B02)

摘　　要：蝶形拱桥的拱肋由于外倾其非线性行为规律较之普通拱桥更加难以掌握,传统的未充分考虑非线性影响的设计方法已不再适用.在自编程序的基础上,全面分析了外倾角、矢跨比、含钢率等设计参数对蝶形拱桥外倾拱非线性行为的影响及规律.结果表明:偏载对加载侧拱肋拱顶横向位移的影响较大,而另一侧较小;斜索体系对拱肋横向位移和面外弯矩的影响均是有利的;拱顶横向位移的影响系数随着外倾角、矢跨比和索拱平面间夹角的增大而增大;位移计算时单元初内力宜由施工阶段分析得到,面外弯矩计算时可采用一次成桥的简化方法进行计算.Because the arch rib of a butterfly-shaped arch bridge is inclined outward,its nonlinear mechanical behavior is more difficult to master compared with ordinary arch bridges.Traditional design methods which do not take nonlinear influence into consideration are not applicable any more.On the basis of self-compiled program,the influence of many design parameters on nonlinearity behavior of outward inclined arches of butterfly-shaped arch bridge,such as the angle of depression,rise-span ratio,steel ratio and so on,and the rules were studied.The results show that：（1）The eccentric load has had a bigger influence on the lateral displacement of arch vault at the loading side relative to the other side;（2）It is favorable for the lateral displacements and outer bending moments of arch ribs when the stayed cable system was adopted;（3）The lateral displacements will increase as the angle of depression gets bigger,and the same conclusion can also be drawn from rise-span ratio and the angle between cable plane and arch plane;（4）The initial forces of elements should be obtained based on the analysis of conventional construction methods when the displacements of arch rib are calculated,and the initial force can be obtained by the simplified method of built a bridge at once when the outer bending moments are calculated.

关 键 词：桥梁工程 蝶形拱桥 非线性行为 增量迭代法 外倾角 矢跨比 

分 类 号：U448.225[建筑科学—桥梁与隧道工程]