大跨度铁路钢桁梁斜拉桥刚度设计及取值研究  

Research on the Stiffness Design and Its Value for Long Span Railway Steel Truss Cable-stayed Bridge

作　　者：陈克坚[1] 李永乐[2] 李龙[2] 曾永平[1] 

机构地区：[1]中铁二院工程集团有限责任公司,成都610031 [2]西南交通大学,成都610031

出　　处：《铁道工程学报》2014年第3期66-71,共6页Journal of Railway Engineering Society

基　　金：铁道部重大科研课题(2009G004-D)资助

摘　　要：研究目的：通过统计国内外已建成并安全运营的大跨度铁路钢桁梁斜拉桥刚度参数，参考国内外现有规范，结合铁路斜拉桥的刚度特点，分析大跨度铁路钢桁梁斜拉桥的刚度指标。在此基础上，通过车桥耦合振动的分析方法，分析大跨度铁路钢桁梁斜拉桥高跨比、宽跨比对车辆与桥梁的动力响应影响，提出大跨度铁路钢桁梁斜拉桥的刚度取值范围。研究结论：（1）结合已建成的大跨度铁路钢桁梁斜拉桥及现有规范，考虑荷载差异，大跨度铁路钢桁梁斜拉桥竖向刚度可适当偏低，大跨度铁路钢桁梁斜拉桥竖向挠跨比设计值可取为1／500～1／800；（2）设计风速时横向挠跨比可放宽到1／1000—1／2000，可行车风速下横向挠跨比限值按规范取为1／4000；（3）桁架高跨比可取为1／25～1／40，桁架宽跨比可取为1／25—1／35；（4）本文研究成果对今后大跨度铁路斜拉桥初步设计工作具有一定的指导意义。Research purposes： The stiffness design parameters of most of long span railway steel truss cable - stayed bridges in safe operation are summarized firstly. Referring to current codes around the world, and considering stiffness characteristics of railway cable -stayed bridge, the stiffness indexes of long span railway steel truss cable -stayed bridges are discussed. Then, the dynamic responses of vehicles and bridge are calculated by the coupled vibration method of vehicle - bridge systems to explore the effect of depth - span ratio and width - span ratio. And the reasonable value ranges of the stiffness design indexes are presented for long span railway steel truss cable - stayed bridges. Research conclusions： （ 1 ） According the existing long span railway steel truss cable - stayed bridges and current codes, considering the difference of loads, the requirement of vertical stiffness of long span railway steel truss cable - stayed bridges can be reduced to certain degree. The ratio of vertical deflection to span should be in the range of 1/500 - 1/800 for the design of long span railway steel truss cable - stayed bridges. （ 2 ） The ratio of lateral deflection to span at the design wind speed can be up to 1/1 000 - 1/2 000, the ratio of lateral deflection to span at the wind speed allowing train operation should be less than 1/4 000 according to the current code. （3） The ratio of truss height to span should be taken as 1/25 - 1/40, the ratio of truss width to span should be 1/25 - 1/35. （4） In this paper, the research results can provide the valuable reference for the design of long span railway steel truss cable - stayed bridge.

关 键 词：铁路斜拉桥 刚度 挠跨比 高跨比 宽跨比 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]