大跨度拱桥拱肋线形调整中的扣索索力优化

将最优化计算理论引入到大跨度拱桥拱肋的线形调整中,采用有限元计算同优化分析相结合的方法来对扣索索力调整量进行逆向求解,解决了线形调整中的索力精确计算问题;索力的优化计算是以拱肋各标高控制点的高程偏差平方和最小为优化目标,拱肋的内力及各个控制点的变位为状态变量,采用一阶分析法对设计变量——索力调整量进行迭代优化;基于 ANSYS 软件的优化分析功能,将该方法应用到一座钢管混凝土拱桥拱肋合拢前的线形调整中,取得了很好的应用效果。

OPTIMIZATION OF STAYED-BUCKLE CABLE FORCES DURING ADJUSTMENT OF THE LINE-SHAPE ON LONG SPAN ARCH BRIDGE

An optimization method is introduced to the adjustment of the arch line-shape for long spans arch bridge. The method of FEM analysis combined with optimization is applied to the inverse calculation of the cable forces. Designated as design parameters, the cable forces are acquired by minimizing the square sum of the altitude deviation of all altitude-controlled nodes. The first order optimization method is employed. Based on the FEM program-ANSYS, the method is implemented to adjust the line-shape of a CFST- arch bridge before folding. The result of optimization of the cable forces shows that this method is successful and effective.