预制蝶形腹板混凝土箱梁抗弯性能研究

为了解预制蝶形腹板混凝土箱梁在荷载作用下的受力特点、破坏形态、变形能力以及腹板中钢筋内力分布等情况,设计制作了预制蝶形腹板混凝土箱梁试件,并对其受弯性能进行了试验研究,采用对称加载,得到了完整的荷载-挠度曲线,沿高度纵向应变曲线、钢筋屈服曲线、沿纵向跨径方向挠度曲线。研究表明,在对称荷载作用下,预制蝶形腹板混凝土箱梁表现为弯曲破坏,同时,伴随着弯剪断腹板接缝处出现断裂,结构失效。针对挠度,对比分析了费氏空腹理论变形公式计算值、有限元分析值和试验值,三者吻合性良好,研究结果可为预制蝶形腹板混凝土箱梁的进一步研究和工程应用提供参考。

Study of Bending Performance of Precast Butterfly Web Concrete Box Girders

In order to understand the precast butterfly wen box girder stress characteristics,failure form,deformation capacity and internal force distribution of the steel bars in the web,a precast butterfly web concrete box is designed and manufactured.The beam model specimens are loaded with symmetrical distribution to obtain a complete load-deflection curve,along the height longitudinal strain curve,the steel bar yield curve,and the deflection curve along the longitudinal span direction,to conduct experimental research on its bending performance.The results have shown that under the action of symmetrical loads,the butterfly-shaped web box girder fails in bending,and the joints of the webs are broken together with the bending and shearing,resulting in structural failure.According to the deformation formula deduced by Fischer’s fasting principle and the comparative analysis between the finite element simulation value and the test value,the coincidence performance is good.The actual measurement results verify the rationality of the finite element and theoretical formulas,and the research results can provide a reference for the further research and engineering application of the butterfly web box girders.