公路钢混组合梁装配化施工技术

Prefabricated Construction Technology of Highway Steel-Concrete Composite Beam

武倘寻高速公路以天生桥特大桥为代表的钢混组合梁桥采用装配化施工工艺,组合梁采用下部两片工字钢上部混凝土面板组成一榀,宽度5.5m,跨度40m,重量194t。工字钢分段在工厂加工成型,运抵预制场胎架上拼装,上部混凝土面板采用预制标准件,安装到工字钢上后采用微膨胀混凝土浇筑横向湿接缝和预留孔洞形成整体。组合梁整体运输安装后浇筑纵向湿接缝。采用混凝土预制标准件加后浇孔、缝的方式代替整体现浇,解决了内部模板拆装困难的问题,施工速度快,有利于减小混凝土收缩徐变对组合梁受力的影响。

The steel-concrete composite beam bridge represented by Tianshengqiao Bridge in Wuchangxun Expressway adopts prefabricated construction technology.The composite beam is composed of two I-beams at the lower part and concrete panels on the upper part,with a width of 5.5m,a span of 40m,and a weight of 194t.The I-steel section is processed and formed in the factory,and assembled on the frame of the prefabricated yard.The upper concrete panel is prefabricated standard parts.After installation on the I-steel,the transverse wet joints and reserved holes are poured by micro expansion concrete to form a whole.The longitudinal wet joints were poured after the overall transportation and installation of the composite beam.The use of precast concrete standard parts plus post-pouring holes and seams instead of integral cast-in-place,solves the problem of difficult disassembly and assembly of the internal formwork,and has a fast construction speed,which is beneficial to reduce the impact of concrete shrinkage and creep on the force of the composite beam.