三跨上承式预应力混凝土拱桥优化设计  

Optimal design of three-span prestressed concrete deck arch bridge

作　　者：惠卓[1] 刘钊[1] 黄晓东[2] 周青虎[1] 

机构地区：[1]东南大学土木工程学院,南京210096 [2]南京市市政设计研究院,南京210008

出　　处：《东南大学学报（自然科学版）》2007年第2期296-300,共5页Journal of Southeast University：Natural Science Edition

摘　　要：在分析预应力布置位置对三跨上承式拱桥内力和拱脚推力影响的基础上,阐明了该类桥型预应力筋的布置原则.同时,为在设计时考虑减小拱脚不平衡推力这一因素,提出了基于敏感性分析的首控截面应力双控设计法、首控拱脚净推力双控设计法以及直接利用优化理论进行设计等3种合理优化设计方法.这些设计法针对该类桥型的特点,利用在拱顶梁中分别布置一定数量的上下偏心的预应力筋来优化结构的内力和满足各部分的位移限制要求.通过对南京三山桥工程的设计计算,表明该设计方法完全可以满足设计要求,并可供相关工程参考验证.On the basis of analyzing effect of prestressed tendon layout on internal force and thrust at springer, the principle of prestressed tendon layout for three-span prestressed concrete deck arch bridge is illustrated. In order to consider the reduction of the thrust at springer, three optimization design methods, i.e. method by firstly controlling stress of section based on sensitivity analysis, method by firstly controlling thrust at springer based on sensitivity analysis, and design method based on optimum theory, are suggested. Combined with that the influence of the prestressed tendon layout on mechanics characteristic of three-span prestressed concrete deck arch bridge is taken into account in these methods, and demand of internal force and displacement in design is satisfied by using upward and downward eccentric layout of prestressed tendon. The calculation of the Nanjing Sanshan bridge engineering is taken as an example, and it is shown that the new design methods are reasonable and. can meet the demand of engineering design.

关 键 词：上承式预应力混凝土拱桥 优化设计方法 拱脚推力 二期预应力筋 

分 类 号：TU312.1[建筑科学—结构工程] U448.215[建筑科学—桥梁与隧道工程]