哑铃形钢管混凝土拱肋施工过程爆仓分析研究

Study on the Process of Broken Accident for CFST Arch Ribs of Dumbbell-shaped Cross Section

建立了哑铃形钢管混凝土拱肋腹腔灌注混凝土施工的有限元实际模型,分析了注浆过程中拱肋各个特征断面腹板应力及变形的变化规律;还分析了采取加设拉杆措施时,腹腔的腹板与钢管交界点和腹板中点的应力及变形,以及拉杆本身的受力特性。研究结果表明,拱脚附近最容易发生"爆仓"事故。拉杆能够缓解腹腔钢板屈服,但随着压强增大,拉杆首先破坏,可以根据不同的受力情况设置不等距的拉杆,但拉杆不能设置过密,太密的拉杆设置反而会使拱肋其他断面较拱脚更为不利。研究结论对哑铃型钢管混凝土拱肋的设计和灌注施工具有一定的参考价值。

The actual finite element model of filling concrete into the dumbbell-shaped steel tubular arch rib was built.The web changes of the stress and deformation of the various feature sections are analyzed during the rib grouting process.Then the stress and deformation of the point connecting the web with the pipe and the web midpoint are analyzed when taking the links measure and also the links force characteristics by itself was investigated.The results show that broken accident most likely to happen near the arch foot.Links can retard the web plates yielding,but with the pressure accretion,the links yield firstly and the links can be set in different distance according to different loads.But the links can not be set too dense,or otherwise the other rib cross-section is more negative than the arch foot.The conclusions have a certain value reference for design and perfusion construction of the dumbbell-shaped CFST arch rib.