混凝土薄壁箱梁变形与裂缝试验研究与分析

Research and Analysis on the Crack and Deformation of Concrete Thin-Walled Box Girder

在混凝土薄壁箱梁模型抗弯性能全过程试验研究的基础上,重点分析了混凝土薄壁箱梁抗弯挠度变形与裂缝分布规律.通过试验证实了混凝土薄壁箱梁在正常使用极限状态下,最大裂缝宽度和跨中挠度均满足规范要求,其开裂弯矩按GB 50010-2002规范公式计算与实测值吻合良好;将混凝土薄壁箱梁截面等效为工字型截面,其平均裂缝间距、最大裂缝宽度和跨中挠度验算,按GB 50010-2002规范或JTG D62-2004规范公式进行验算均与实测值吻合良好;考虑翼缘宽度折减后,其计算结果更加接近实测值,但相差在5%以内,在实际工程设计中可以不考虑其影响.图5,表3,参12.

Basis on the full test on the flexible behaviors of the concrete thin-walled box girder, the experimental results disclosed the law of deformation and crack. At normal service ultimate state, the maximum cracking width and deformation of concrete thin-walled box girder agree with the request of the code, the experimental value of cracking moment agreed well with the value calculated by the GB 50010-2002 code. Equivalent I-shaped section girder, the experi.mental values of average space between cracking, maximum cracking width and deformation at middle span agreed well with the values calculated by the GB 50010-2002 code or the JTG D62-2004 code. Considering of the shear lag phenomenon of the concrete thin-walled box girder, the calculated values draw closer together experimental values, but error in 5%, in the fact engineering without considering the equivalent calculated coefficient of flange width. 5figs., 3tabs., 12refs.