大跨度无碴轨道连续梁桥后期变形控制方法  

Control method for long term-deformations of long-span continuous bridges with ballastless tracks

作　　者：侯文崎[1] 叶梅新[1] 曹建安[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075

出　　处：《华中科技大学学报（自然科学版）》2011年第7期109-112,127,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：铁道部科技研究开发计划资助项目(2006G009-C-2)

摘　　要：预应力混凝土连续梁后期变形将影响无碴轨道线路平顺性,针对这一问题,以某新建高速铁路大跨度无碴轨道预应力混凝土连续刚构桥为例,通过有限元分析,对比研究了不同后期变形控制方法的控制效果,提出了后期变形联合控制措施.结果表明:延长铺轨时间、预留后张索、设计体外索等方法均可有效减小桥梁的后期变形.铺轨时间以延长0.5a为宜,后张索和体外索可根据桥梁实际变形情况分批张拉.应用联合控制措施,成桥铺轨20a后,桥梁中跨和边跨的后期变形分别被控制在21.9mm和12.8mm内,远小于规范限值.Long term-deformation of pre-stressed concrete continuous girders affect the smoothness of non-ballast tracks. Taking an example, a newly-built high speed railway long-span pre-stressed concrete continuous rigid frame bridge with ballastless track was studied, and the effects of different methods on the later-stage deformation control were compared through FEA （finie element analysis）. Then, a set of coordinate control measures was put forward. Results show that extending track laying time, reserving post-tensioned cables and tensioning external tendons are all effective in decreasing the later-stage deformation of the bridges. Track laying time is appropriate to be delayed for about 0.5 a, post-tensioned cables and external tendons can be tensioned in sequence according to practical deform- ation of bridges. When the coordinate control measures were used, the example bridge＇s 20 a deformation after the track laying was controlled within 21.9 mm for the middle span and 12.8 mm for the side span, which was far less than the deformation limitation.

关 键 词：无碴轨道 后期变形 变形控制 预应力混凝土连续梁桥 体外索 后张钢束 

分 类 号：U212.31[交通运输工程—道路与铁道工程] TU311[建筑科学—结构工程]