斜拉索索力作用下不同形式混凝土主梁受力特性研究
|
摘要
为了解斜拉桥悬臂施工阶段,斜拉索索力作用下主梁的应力分布规律,结合圣维南原理,以宽幅混凝土主梁斜拉桥常用的3种主梁为研究对象(Π形实体边主梁、PK箱形主梁以及箱形中央索面主梁)。采用仿真计算方法,对合龙前最大悬臂施工阶段下,悬臂端索力对主梁的空间受力状态进行分析,归纳出不同形式主梁混凝土斜拉桥应力分布特点。结果显示:主梁应力分布的顺桥向影响范围均近似为1个梁宽,索力对不同形式主梁的传递角度均可取26°;建议大跨度宽幅斜拉桥采用PK箱形;对于中央索面斜拉桥主梁翼缘可以滞后1～2个节段浇筑,降低翼缘的剪力滞效应,提高施工效率。
To examine the stress distribution law of main girder under the action of stay cable forces during the cantilever construction stage of the cable-stayed bridge,following the Saint-Venant′s principle,the three types of main girders that are commonly used in the cable-stayed bridge with wide concrete main girder are taken as the study objective,including theΠ-shaped solid edge girders,PK box girder and box girder carrying central cable plane.The simulation calculation method was used to analyze the effect of cantilever-end cable forces on the spatial load bearing condition of the main girder,in the maximum cantilever construction stage before closure.And the stress distribution characteristics of cable-stayed bridges with different concrete main girders were summarized.The results show that the influential area of main girder stress distribution along the bridge length covers about the width of the a girder,to different types of main girders,the cable force transmitting angle can all be set at 26°.It is suggested that PK box girder be chosen for the long-span cable-stayed bridge with wide deck.For the cable-stayed bridge with central cable plane,the casting of flanges of the main girder can be laid one or two sections behind,so as to reduce the shear lag effect in the flanges and improve construction efficiency.
To examine the stress distribution law of main girder under the action of stay cable forces during the cantilever construction stage of the cable-stayed bridge,following the Saint-Venant′s principle,the three types of main girders that are commonly used in the cable-stayed bridge with wide concrete main girder are taken as the study objective,including theΠ-shaped solid edge girders,PK box girder and box girder carrying central cable plane.The simulation calculation method was used to analyze the effect of cantilever-end cable forces on the spatial load bearing condition of the main girder,in the maximum cantilever construction stage before closure.And the stress distribution characteristics of cable-stayed bridges with different concrete main girders were summarized.The results show that the influential area of main girder stress distribution along the bridge length covers about the width of the a girder,to different types of main girders,the cable force transmitting angle can all be set at 26°.It is suggested that PK box girder be chosen for the long-span cable-stayed bridge with wide deck.For the cable-stayed bridge with central cable plane,the casting of flanges of the main girder can be laid one or two sections behind,so as to reduce the shear lag effect in the flanges and improve construction efficiency.
引文
[1]赖亚平,王科,李锦.泸州沱江四桥主桥扭转、剪力滞效应及关键构造研究[J].桥梁建设,2016,46(4):17-22.
[2]任蒙,付坤,陈毅明,等.沌口长江公路大桥加劲梁选型与设计[J].世界桥梁,2017,45(1):5-9.
[3]孙文会.宽幅矮塔斜拉桥受力特性研究(硕士学位论文)[D].武汉:武汉理工大学,2010.
[4]周绪红,狄谨,戴公连.大跨径预应力混凝土斜拉桥主梁节段模型的研究[J].土木工程学报,2005(3):59-63.
[5]方志,曹国辉,王济川.钢筋混凝土连续箱梁剪力滞效应试验研究[J].桥梁建设,2000(4):1-3.
[6]关淑萍,李江林.独塔单索面预应力混凝土斜拉桥静载试验[J].桥梁建设,2012,42(2):53-58.
[7]聂建国,李法雄,樊建生.组合梁斜拉桥桥面有效宽度分析[J].哈尔滨工业大学学报,2007,39(2):718-724.
[8]詹建辉,彭晓彬.大跨度组合梁斜拉桥结构设计方案研究[J].桥梁建设,2016,46(4):85-91.
[9]舒江,师少辉,朱玉.武汉西四环汉江特大桥总体设计[J].桥梁建设,2017,47(6):84-88.
[10]余祥亮.坦桑尼亚基甘博尼大桥设计[J].世界桥梁,2017,45(1):1-4.
[11]彭建萍.混合梁斜拉桥不对称双悬臂施工技术[J].桥梁建设,2018,48(1):118-122.
[2]任蒙,付坤,陈毅明,等.沌口长江公路大桥加劲梁选型与设计[J].世界桥梁,2017,45(1):5-9.
[3]孙文会.宽幅矮塔斜拉桥受力特性研究(硕士学位论文)[D].武汉:武汉理工大学,2010.
[4]周绪红,狄谨,戴公连.大跨径预应力混凝土斜拉桥主梁节段模型的研究[J].土木工程学报,2005(3):59-63.
[5]方志,曹国辉,王济川.钢筋混凝土连续箱梁剪力滞效应试验研究[J].桥梁建设,2000(4):1-3.
[6]关淑萍,李江林.独塔单索面预应力混凝土斜拉桥静载试验[J].桥梁建设,2012,42(2):53-58.
[7]聂建国,李法雄,樊建生.组合梁斜拉桥桥面有效宽度分析[J].哈尔滨工业大学学报,2007,39(2):718-724.
[8]詹建辉,彭晓彬.大跨度组合梁斜拉桥结构设计方案研究[J].桥梁建设,2016,46(4):85-91.
[9]舒江,师少辉,朱玉.武汉西四环汉江特大桥总体设计[J].桥梁建设,2017,47(6):84-88.
[10]余祥亮.坦桑尼亚基甘博尼大桥设计[J].世界桥梁,2017,45(1):1-4.
[11]彭建萍.混合梁斜拉桥不对称双悬臂施工技术[J].桥梁建设,2018,48(1):118-122.