大跨径上承式钢管混凝土拱桥拱上建筑施工顺序优化

王发正¹，张馨²

1.招商局重庆交通科研设计院有限公司，重庆  400067；2.重庆市城市建设高级技工学校，重庆  402247

摘要：对大跨径上承式钢管混凝土拱桥拱上建筑施工顺序进行优化，采用有限元软件Midas/Civil对拱桥建模并进行数值模拟分析，计算施工方案1（从拱脚向拱顶架设拱上立柱，再从拱脚向拱顶架设T梁）、施工方案2（从拱顶向拱脚架设拱上立柱，再从拱顶向拱脚架设T梁）、施工方案3（从拱脚向拱顶方向同时架设拱上立柱和T梁）、施工方案4（从拱顶向拱脚方向同时架设拱上立柱和T梁）等4种方案下主拱圈控制截面的位移、应力和稳定性。在保障工程施工安全的前提下，遵循对称加载的原则，优化调整拱上建筑施工顺序。结果表明：成桥后施工方案3的位移和应力最小，且施工拱上建筑中，位移和应力变化幅度最小，施工方案3为最优施工方案。施工方案3对应的施工顺序满足结构施工安全的要求，且拱上立柱和桥面T梁可同步施工，有效缩短施工周期。

关键词：上承式钢管混凝土拱桥；数值分析；施工顺序；优化

Construction sequence optimization for the construction of arch building on a long-span continuous steel pipe concrete arch bridge

WANG Fazheng¹, ZHANG Xin²

1.China Merchants Chongqing Communications Technology Research＆Design Institute Co., Ltd., Chongqing 400067, China;

2.Chongqing Urban Construction Senior Technical School, Chongqing 402247, China

Abstract: In order to optimize the construction sequence of the upper arch structure of a large-span steel pipe concrete arch bridge, the finite element software Midas/Civil is used to model and numerically analyze the arch bridge. The displacement, stress, and stability of the main arch ring control section are calculated under four construction schemes: Scheme 1 (erecting the upper column from the arch foot to the arch crown and then the T-beam from the arch foot to the arch crown), Scheme 2 (erecting the upper column from the arch crown to the arch foot and then the T-beam from the arch crown to the arch foot), Scheme 3 (simultaneously erecting the upper column and T-beam from the arch foot to the arch crown), and Scheme 4 (simultaneously erecting the upper column and T-beam from the arch crown to the arch foot). Ensuring construction safety and following the principle of symmetric loading, the construction sequence of the upper arch structure Is optimized. Results show that after the bridge is completed, the displacements and stresses of Scheme 3 is the smallest with minimal variations during construction. The Scheme 3 is the optimal construction scheme. The construction sequence corresponding to Scheme 3 meets the safety requirements of structural construction, allowing simultaneous construction of the upper columns and bridge deck T-beams, effectively reducing the construction period.

Keywords: a long-span continuous steel pipe concrete arch bridge; numerical analysis; construction sequence; optimization