基于信息共享猴群算法的混合梁斜拉桥索力优化

Optimization of Cable Force for Cable-stayed Bridge with Mixed Stiffening Girders by Using Information Exchange Based Monkey Algorithm

斜拉桥的索力对桥梁的受力特点及应力分布起着关键作用,为了得到更加合理的成桥索力,提出采用猴群算法来优化索力。针对标准猴群算法缺乏信息交流造成的计算冗余问题,提出了基于距离矩阵信息交流机制的信息共享猴群算法,以提高个体利用率,增加算法寻找到全局最优概率。最后将所提算法应用于数值算例,并将其与标准算法进行对比。寻优结果表明改进后的猴群算法相较于标准算法在寻优精度上改善效果明显。最后将该算法应用于一座大跨度混合梁斜拉桥的索力优化上,经过优化,全桥应变能、主梁弯矩和主塔的最大弯矩值均有下降,优化后的桥梁受力更加合理、安全。

The cable force of cable-stayed bridge plays a key role to determine the strain distribution.To obtain a more reasonable cable force,monkey algorithm has been employed.This paper proposed a method which based on the distant matrix to solve the problem of calculation redundancy.The proposed method can take fully use of the monkey individuals,and this can get a greater chance to obtain the global minimum.Five numerical examples have been employed to verify the performance of proposed algorithm.Finally,the proposed algorithm has been used in a long span cable-stayed bridge,and the result shows that the tension-compression strain energy has a great decline.Additionally,the bending moment of the girder and the tower both descend greatly.After optimization,the cable forces are more reasonable and the structure is safer.