摘要
整体预制工字形钢板组合梁是一种在梁场现浇混凝土来实现钢混整体预制的预制梁,适用于连续长大高架中的中等跨径的控制节点段,具有不改变架设设备而实现连续快速施工的优势,但相关设计施工、收缩和徐变、负弯矩裂缝控制的应用研究较少。现依托某高速连续高架,对50 m跨径工字组合梁桥设计、施工进行了详细介绍,对比分析了整体预制梁的应力和经济性差异,探讨了混凝土板收缩和徐变影响、裂缝控制等设计关键技术。分析结果可见:(1)采用整体预制钢板组合梁架设便捷,综合成本较低;(2)3孔连续梁仅采用逐个支点回落方式,可有效控制负弯矩区开裂风险,且便捷经济;(3)设计中,应充分考虑收缩和徐变对应力和挠度的影响。整体预制工字形钢板组合梁在长大高架工程中具有推广应用价值。
The integral prefabricated I-shaped steel plate composite girder is an integral precast girder with steel made in factory and concrete cast onsite.It is widely used in medium span bridges of long and continuous viaduct design.It has the advantage of continuous and rapid construction without changing the available erection equipment,but the research and application on related design construc tion,shrinkage and creep influence,and crack control of negative bending moment zone remains limited.This article studies the details of design and construction of a 50m-span I-shaped composite girder in a high-speed continuous viaduct project.The structural analysis and economic merits of kinds of precast girders are analyzed,and the key design technologies such as shrinkage and creep influence,and crack control of the concrete slab are discussed.Based on the results(1)Construction of the integral prefabricated I-shaped steel plate composite girder is fast and convenient with lower comprehensive total cost.(2)The construction of 3-span continuous bridge can effectively control the cracking risk in the negative bending moment zone by falling back the supports one by one,which is convenient and economic.(3)The structural design needs comprehensive consideration on the influence of shrinkage and creep of composite girder stress and deflection.It is proved that the integrally prefabricated I-shaped steel plate composite girder has great value and wide application in large viaduct projects.
出处
《上海公路》
2022年第3期42-46,51,M0004,M0005,共8页
Shanghai Highways
关键词
桥梁工程
钢板组合梁
设计施工
结构分析
收缩和徐变
负弯矩区裂缝
bridge engineering
steel plate composite girder
design and construction
structural analysis
shrinkage and creep
cracks in negative bending moment zone
