长距离输水管道工程超大跨径托管桥方案比选研究

Comparison and Selection of Ultra-Large Span Trusteeship Bridge Schemes for Long-Distance Water Conveyance Pipeline Projects

输水管道跨越沟渠、河道、山谷常采用桁架跨越、拱桥跨越、悬索跨越、斜拉索跨越等形式,但各种跨越形式均存在一定的问题。文章介绍准东供水工程长距离输水管道跨越渠道采用变截面连续钢箱梁桥,最大单跨跨径150m,为国内规模最大的同类型托管结构,其设计荷载为1.8m直径有压输水管,每延米水管及满管水重与3车道汽车满载相近。通过对悬索桥、拱桥、混凝土连续梁桥及变截面连续钢箱梁桥四种桥型从施工工期、经济性、抗震性能及抗风性能等多方面进行综合分析,最终选择了受冬期影响最小(施工期最短)且造价最低的80m+150m+80m变截面连续钢箱梁桥方案。输水管桥具有大跨径、窄桥面、风荷载大等特点,文中介绍的设计理念、计算方法、施工方案,可为类似工程提供借鉴。

To transport water across ditches,rivers,and valleys,truss crossing,arch bridge crossing,suspension bridge crossing,and cable-stayed bridge crossing are commonly used.However,each of these crossing methods has its own set of challenges.This paper introduces the use of a variable-section continuous steel box girder bridge for the long-distance water conveyance pipeline in the Zhundong Water Supply Project.With its maximum single-span length of 150 meters,it is the largest trusteeship structure of its kind in China.The design load is for a 1.8-meter diameter pressurized water pipe,with the per-meter weight of the pipe and full water load similar to that of a three-lane fully loaded automobile.A comprehensive analysis is conducted on four types of bridges:suspension bridges,arch bridges,concrete continuous beam bridges,and variable-section continuous steel box girder bridges,considering construction period,cost,seismic,and wind resistance.Ultimately,an 80m+150m+80m variable-section continuous steel box girder bridge,which is least affected in winter(shortest construction period)and lowest in cost,was selected.The water pipeline bridge features large span,narrow bridge deck,and significant wind load.The design concepts,calculation methods,and construction schemes introduced in this article can provide references for similar projects.