摘要
纳晴高速牂牁江特大桥主桥为跨径1080 m的单跨钢桁梁悬索桥。主桥采用纵向低阻尼指数黏滞阻尼器+横向弹性抗风支座+跨中柔性中央扣+边缆限位拉索+竖向塔连杆的多重约束体系。加劲梁采用板桁结合结构形式,由钢桁梁和正交异性钢桥面板组成。桥塔采用门式框架混凝土塔,桥塔基础为超大直径3.8 m的端承桩+分离式承台。主缆采用标准抗拉强度1960 MPa的高强度镀锌铝稀土合金钢丝,跨度布置为(265+1080+435)m。吊索、柔性中央扣及限位拉索采用1960 MPa级镀锌铝稀土合金密封钢丝绳,索体外层由3层Z形异形钢丝环环扣合形成全密封结构,极大提高了缆索系统的耐久和抗疲劳性能。边缆设置限位拉索,有效限制了活载作用下边缆的竖向位移。该桥纳雍岸采用山区岩石地基复合型重力式锚碇,通过合理利用齿坎和岩石夹持效应,锚体工程量节省近20%。悬索桥加劲梁采用陡峻峡谷无起吊平台方案架设,有效解决了山区大跨悬索桥加劲梁吊装场地受限的难题。
The main bridge of Zangke River Bridge of the Nayong-Qinglong Expressway is a suspension bridge with a main suspended span of 1080 m,featuring a restraint system that includes longitudinal viscous dampers with low damping exponent,lateral elastic wind-resistant bearings,midspan flexible central buckle,stabilizing cables linked to main cables in the side spans,and the vertical connecting rods in towers.The stiffening girder consists of steel trusses that act compositely with the overlaid orthotropic steel deck panels.The towers are portal-frame concrete structures,where the two columns of each tower rest on individual pile caps that are supported by end-bearing piles with a diameter of 3.8 m.The main cables,which are composed of high-strength galvanized aluminum-rare earth alloy steel wires with a nominal tensile strength of 1960 MPa,are arranged in three spans of 265,1080 and 435 m.The hanger cables,flexible central buckles and stabilizing cables are made of galvanized aluminum-rare earth alloy steel wires with a tensile strength of 1960 MPa,the steel wires of each cable are wrapped with three layers of steel Z wires to be locked coil cables with better durability and fatigue resistance.The stabilizing cables linked to the main cables in the side spans effectively limit the vertical displacement of the side-span main cables under live loads.By taking effective use of the tenon and rock clamping effect,the engineering quantity of the Nayong-side gravity anchorage composite with rock footing was reduced by about 20%.The erection of the stiffening girder was conducted smoothly in the limited space of the valley,with no assistance of lifting platform.
作者
刘新华
李秋
张坤
欧阳泽卉
LIU Xinhua;LI Qiu;ZHANG Kun;OUYANG Zehui(CCCC Second Highway Consultants Co.,Ltd.,Wuhan 430056,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2024年第6期110-116,共7页
Bridge Construction
基金
贵州省交通运输厅科技项目(2022-122-021)。
关键词
悬索桥
钢桁梁
锌铝稀土合金钢丝
密封吊索
限位拉索
复合式锚碇
加劲梁架设
桥梁设计
suspension bridge
steel truss
galvanized aluminum-rare earth alloy steel wire
locked coil cable
stabilizing cable
composite anchorage
stiffening girder erection
bridge design
作者简介
刘新华,1981-,男,正高级工程师,2004年毕业于湖南工业大学土木工程专业,工学学士,2007年毕业于湖南大学桥梁与隧道工程专业,工学硕士,2021年毕业于长沙理工大学土木工程专业,工学博士。研究方向:大跨与新型桥梁结构设计,E-mail:601446430@qq.com;李秋,1990-,男,高级工程师,2013年毕业于哈尔滨工业大学道路桥梁与渡河工程专业,工学学士,2015年毕业于哈尔滨工业大学建筑与土木工程专业,工程硕士。研究方向:大跨桥梁结构设计,E-mail:617576343@qq.com;张坤,1993-,男,工程师,2016年毕业于郑州大学道路桥梁与渡河工程专业,工学学士,2019年毕业于东南大学土木工程专业,工学硕士。研究方向:桥梁结构设计,E-mail:718160477@qq.com;欧阳泽卉,1991-,男,高级工程师,2012年毕业于湖南大学土木工程专业,工学学士,2015年毕业于湖南大学建筑与土木工程专业,工程硕士。研究方向:桥梁结构设计,E-mail:504320608@qq.com。
