摘要
以96 m正交异性板道砟桥面钢桁梁为研究对象,根据主桁下弦杆为拉弯构件的受力特点,设计中适当增大主桁下弦杆的竖向抗弯刚度。通过取消传统的钢混组合式道砟槽板,采用新型MMA防水体系+CAP轻质垫层+钢挡砟墙桥面系布置,减小二期恒载30%以上,有效减小了主桁用钢量。为了解决正交异性钢桥面板活载加载计算工作量大的问题,提出了正交异性板桥面系虚拟影响面加载法。钢桁梁的各项刚度指标分析结果表明:本桥具有较大的整体刚度,满足200 km/h的列车行车速度要求。结合桥址实际情况,在钢桁梁小夹角上跨既有铁路状况下,采用转体施工法进行钢桁梁架设。
A 96 m span steel truss girder with orthotropic plate and ballast deck was taken as a research object. According to the mechanical characteristics that lower chords of main truss are bending - tension members, verti- cal flexural rigidity of main truss lower boom was properly increased in the design. Through eliminating tradition- al steel - concrete combined type of ballast tank plate, a new floor system with MMA waterproof system concrete with adhesive pads and steel ballast wall was adopted, by which, secondary dead load was decreased by more than 30% and steel consumption of main truss was effectively reduced too. In order to solve the problem that workload of live - load loading calculation is very heavy in orthotropic steel deck, virtual influence surface loading method was put forward. Rigidity index analysis results of the steel truss girder show that, the bridge has a larger overall stiffness, which meets the requirement for 200 km/h train traffic. Based on the actual situation of bridge site, under the condition of the steel truss girder crossing existing railway with a small angle, the steel truss gird- er was erected by rotation construction method.
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2012年第6期18-23,共6页
Journal of Railway Science and Engineering
关键词
正交异性板
道砟桥面
钢桁梁
CAP轻质垫层
转体施工法
板桁组合结构
虚拟影响面加载法
orthotropic plate
ballast deck
steel truss girder
concrete with adhesive pads
rotation construction method
plate -truss composite structure
virtual influence surface loading method
