拉萨柳梧大桥施工监控技术研究

简述了拉萨柳梧大桥概况及其主桥上部结构(主、副拱)的施工.根据施工特点确定了施工监控的主要内容:主跨基础桩身应力监控、主桥线形监控、应力监测、吊杆内力监测.采用空间有限元分析方法时施工阶段进行了验算,并对施工工序进行了优化.结果表明,内、外拱吊杆的张拉顺序和吊杆内力控制值对各施工阶段以及成桥后拱桥结构状态影响较大;结构特点决定了线形、应力和吊杆内力在施工过程中变化频繁,施工监控中应对桥梁动态跟踪;主桥预拱度设置合理,施工阶段的理论值和实测值吻合,各项监控内容均达到了预期效果.

Study on Construction Supervision of Lhasa Liuwu Bridge

The construction of Lhasa Liuwu Bridge and its main bridge superstructure (main arch and sub-arch) were described briefly.According to construction features, the main contents of construction supervision were determined, including main span foundation pile stress monitoring, main bridge geometric configuration control and stress monitoring, suspender internal force monitoring.Checking calculation of different construction phases and the construction process optimization were carried out by using finite element analysis method.The result shows that (1) tension sequence of internal and external arch suspenders and control value of suspender internal force has great influence on all construction phases and structural state of finished bridge; (2) structural characteristics result in frequent changes of geometric configuration, stress and suspender internal force, therefore, the bridge should be supervised dynamically during construction; (3) main bridge camber is reasonable, theoretical and measured values coincide in construction phase, and the effect of all supervision contents are satisfied.