外倾索面部分斜拉桥PC箱梁技术指标分析

摘要

Based on design of PC box girder of cable-stayed bridge with outside dumping cable surface named Jiayue Bridge,Nanping Bridge and Chibilu Bridge,this paper made statistics and analysis to key design parameters such as box girder section type,beam height value,beam bottom line type,no cable length,unit consumption of concrete,prestressed steel beam unit volume content and ordinary steel unit volume content,etc.This paper puts forward the concept of “load effect distribution ratio” to evaluate the force distribution of stay cable and girder,and evaluate the three bridges respectively,so to reveal the intrinsic relationship between the design of stay cable,girder and tower and the “load-effect distribution ratio”.At the same time,the stress characteristics of the PC box girder of the cable-stayed bridge with outside dumping cable surface are analyzed from the aspects of vertical and horizontal force transmission path of the PC box girder,the vertical stiffness of the box girder and the structural self-vibration characteristics.%依据嘉悦大桥、南屏大桥和赤壁路桥3座外倾索面部分斜拉桥PC箱梁的设计,统计分析其箱梁断面型式、梁高取值、梁底线型、无索区长度等关键设计参数和混凝土单位用量、预应力钢束单位体积含量、普通钢筋单位体积含量等重要设计指标.提出“荷载效应分配比”概念以评价部分斜拉桥索、梁受力分配情况,并对3座桥进行相应评估,揭示部分斜拉桥索、梁、塔设计与“荷载效应分配比”的内在关系.同时,还从PC箱梁纵横向传力路径、箱梁竖向刚度、结构自振特性等指标分析外倾索面部分斜拉桥的PC箱梁受力特性.