港珠澳大桥大节段钢箱梁吊装过程优化分析

Analysis and Optimization of Large Segment Hoist of Steel Box Girder for the Hong Kong-Zhuhai-Macao Bridge

针对港珠澳大桥连续钢箱梁桥大节段吊装起吊长度长、重量大、控制精度高等特点,根据吊装过程中控制要求,采用ANAQUS进行了吊装过程中的大节段受力分析、吊点优化分析及支座预偏分析。分析结果表明,采用原设计方案进行大节段吊装,吊装过程中边跨大节段挠度最大值为27mm,应力最大值达到-49.5 MPa。为保证吊装过程中主梁最大变形不超过5mm,进行吊点优化后,在吊点数量仅增2个的情况下,经过吊点优化后的大节段挠度最大值为1.91mm,为原设计的7.07%,应力最大值-6.36 MPa,为原设计的12.85%,进行支座预偏分析时应综合结构受力变形、温差变形等,分析成果可用于指导工程实践。

In view of the characteristics of the long length,large weight and high precision of the large segments continuous box girder for the Hong Kong-Zhuhai-Macao Bridge,according to control requirements for hoist and erection,ABAQUS is used for analysis of hoisting force,optimization of hoist points and pre-bias of bearings.The results show that if adopting the initial hoisting plans,the maximal deflection of side span reaches about 27 mm,and the maximal stress reaches about -49.5 MPa.In order to make the deflection of the main girder lower than 5 mm,after optimization is achieved,in the case that the hoist point number only adds two,the deflection of big segment reduces to 1.91 mm which is 7.07% of initial design project;the stress reduces to -6.36 MPa,being 12.85% of initial design project.The structure force and temperature detection in pre-displacement of supports analysis should be comprehensively considered.The study results can provide guidance for construction purpose.