安海湾特大桥钢混结合段C55纤维微膨胀混凝土配合比设计方法研讨

Discussion on Design Method of Proportioning Ratio of C55 Fiber Microexpansion Concrete in Steel-concrete Joint Section of Anhai Bay Bridge

钢混结合段有格室构造,同时钢筋、PBL剪力键和预应力钢绞线相互交错,混凝土振捣困难,为增强混凝土的微膨胀及抗裂性效果,设计采用大流动性的纤维微膨胀混凝土。通过研究不同规范的混凝土配合比设计方法,试配不同掺配合比的混凝土,筛选出符合现场施工的混凝土配合比,同时考虑经济性及耐久性,研讨最优配合比设计方案。

The steel-concrete joint section has a lattice structure. At the same time,the steel bars,PBL shear bonds and prestressed steel strands are interlaced,and it is difficult to vibrate the concrete. At the same time,in order to enhance the micro expansion and crack resistance of the concrete,the design uses large flow fiber microexpansion concrete. By researching the design methods of concrete mix ratios of different specifications,trial-provisioning of concrete with different mix ratios,the concrete mix ratios suitable for on-site construction are screened out,while considering the economy and durability,the optimal mix ratio design scheme is discussed.