非均布对称荷载下抛物形拱结构屈曲研究

Study on buckling of parabolic arch under non-uniform symmetric load

针对抛物形拱结构面内稳定课题的复杂性,对竖向非均布对称荷载作用下无铰抛物形浅拱进行了平面内稳定分析,利用虚功原理对浅拱进行非线性屈曲研究,得到对称荷载下的二次多项式分布时的屈曲控制方程,当荷载系数满足该控制方程时抛物拱发生临界屈曲,为抛物形拱坝的屈曲研究提供了基础;基于荷载强度整体等效折减法给出了非均布对称荷载作用下的屈曲安全系数计算,为相关工程如大跨度抛物线拱桥结构、大跨度抛物线钢结构体育馆顶棚、大跨度厂房屋顶等结构稳定计算提供理论参考。

Aiming at the complexity of the problem of in-plane stability of parabolic arch structures,the in-plane stability analysis of the non-hinged parallax-free shallow arch under vertical non-uniform symmetrical load was carried out.The nonlinear buckling of the shallow arch was studied by using the virtual work principle.The buckling control equation of the quadratic polynomial distribution under symmetric loading was obtained.The buckling of the parabolic arch was studied when the load factor satisfies the control equation,providing the basis for buckling of parabolic arch.Based on the equivalent weight reduction method of load strength,the buckling safety factor calculation under non-uniform symmetrical load is given.For the related projects such as large span parabolic arch bridge structure,large span parabolic steel structure gymnasium ceiling,large span plant roof and other structural stability calculation provide theoretical reference.