中文摘要：

为给特大跨波形钢腹板组合箱梁桥体外预应力设计提供参考,以港珠澳珠海连接线工程前山河特大桥为背景,介绍体外预应力体系的布设、转向与锚固装置的设计细节、体外束保护与减振装置的构造及减振机理。采用有限元软件,建立体外预应力钢束转向块、锚固端节段及运营阶段全桥有限元数值模型,分析转向块及锚固端的局部应力,研究施加体外预应力后运营阶段结构受力情况,比较不同体外预应力张拉工序对成桥状态结构挠度、应力、弯矩等力学性能的影响。结果表明：转向块及锚固端节段满足结构局部应力安全要求;运营阶段结构挠度、混凝土主梁及波形钢腹板应力均满足设计规范要求,结构安全可靠;＂全桥合龙后先张拉中跨,后对称张拉边跨＂的体外束张拉方案为最优方案。

英文摘要：

To provide references to the external prestressing design for mega span composite girder bridge with corrugated steel webs,the Qianshanhe River Bridge,part of the HongkongZhuhai-Macao Link Project,was taken as the study background,to introduce the layout of the external prestressing system,design details of the deviation and anchor devices,external prestressing protection and the composition and working mechanism of the vibration mitigation devices.The finite element software was used to establish the numerical models of the deviators of the external prestressing tendons,the sections at the anchoring end and the overall bridge in the operation period.The load bearing conditions of the structure in the operation period after the external prestressing was added were studied and the influences of different external prestressing tensioning schemes on the load bearing behaviors of the structure in the completed bridge state were compared,including deflection,stress and bending moment.The results indicate that the deviators and sections at the anchoring end meet the local stress safety requirements.The deflection of the structure,stresses in the concrete main girder and corrugated steel webs in the operation period all meet the requirements of the design specification and the structure is safe and reliable.The scheme,in which the external prestressing in the intermediate span is tensioned first and the symmetrical tensioning of the external prestressing in the side spans later after the closure of the overall bridge,is regarded as the optimum one.