钢管混凝土拱桥施工合龙合理状态的遗传搜索

由于钢管混凝土拱桥的受力特点，在施工仿真计算中无法找到倒退分析的起点，为此，尝试嵌入遗传算法来确定钢管拱肋施工合龙前的合理状态，以此作为倒退分析的起点，确定了以扣索索长调整量为变量参数的目标函数，而目标函数需要通过结构仿真计算才能得出相对应的目标函数值，搜索相当复杂，因此采用实数遗传算法，改进了遗传操作，以满足搜索的精度和速度，并用算例搜索出了合龙时拱肋线形的合理状态，经比较其状态是合理的，可以作为倒退分析的起点。

Genetic Searching for Optimized Closure State of CFST Arch Bridge Construction

It is very difficult to find out the initial state of the backward analysis in traditional simulative calculation of bridge construction because of the bearing peculiarity of concrete filled of steel tubular arch bridge. In this paper, the genetic algorithm is introduced to search the optimized closure state in archrib construction, which can be taken as the initial state of backward analysis. According to the detailed analysis, the target function is determined, which takes adjustment increment of cable length as a variable parameter. But the target function can be obtained only through structural simulative calculation, which makes the searching more complicated. So the floating-point genetic algorithm is adopted and the genetic operation is ameliorated to improve precision and speed of the genetic search. Finally the optimized closure state in arch-rib construction is obtained using the improved genetic algorithm in a calculation example. It proves that the results can be used as the initial state for the backward analysis.