斜拉桥索塔锚固区前壁竖向拉-压杆模型  

Vertical STM in Facade Wall of Pylon Anchorage Zone of Cable-stayed Bridge

作　　者：陶齐宇[1] 刘扬[2] 

机构地区：[1]西南交通大学,四川成都610031 [2]长沙理工大学,湖南长沙410114

出　　处：《公路交通科技》2011年第9期46-52,共7页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(50608009)

摘　　要：对斜拉桥箱形截面索塔塔壁预应力锚固体系,采用拉-压杆模型方法对拉索直接锚固的塔柱前壁进行研究。以力法为手段,依据拉-压杆模型的优化原理,确立了体内单锚的拉-压杆模型。以单锚拉-压杆模型为基础,初步构建前壁的拉-压杆模型。取z为拉杆(T3)与结点(1)间的竖向距离,采用力法建立以z为函数的拉杆内力的表达式,利用拓扑优化成果(T2=0)和卡尔丹公式,确定z的数值,自下而上全面解答了前壁的拉-压杆模型,从而准确反映在拉索竖向分力作用下前壁拉、压应力的分布状况。最后,通过对宜宾长江大桥索塔的实例研究,提出α3=23.3°,简化了前壁拉-压杆模型,且具有较好的工程精度,可用于确定索塔锚固区的预应力筋的规格。To the tendon anchorage system in the wall of box pylon of cable-stayed bridge,the facade wall of cable-anchored pylon was researched using strut-and-tie model（STM）.According to the optimization principle of STM,the STM of single anchor was established by means of force method.On the basis of the STM of single anchor,the STM in the facade wall was preliminary built.The expression of internal force in ties about z,the vertical distance between the tie T3 and node 1,was established.Using topology optimization result（T2=0） and Cardan Formula,the value of z was determined,the STM in the facade wall was comprehensively solved.Thus,the distribution of compressive and tensile stresses in the facade wall under the action of vertical component of cable force was accurately reflected.Finally,through researching the pylon of Yibin Yangzte River Bridge,the parameter α3=23.3° was proposed,and the STM in the facade wall was simplified.It has better precision and can be used to determine tendon specification in the anchorage zone of box pylon.

关 键 词：桥梁工程 拉-压杆模型 拓扑优化 索塔锚固区 斜拉桥 计算方法 

分 类 号：U442[建筑科学—桥梁与隧道工程]