基于遗传算法的半刚性连接钢框架设计

采用基于小生镜技术的遗传算法,对半刚性连接钢框架进行优化设计,针对其早熟现象和局部搜索能力差的缺点改进遗传算法。使用自适应策略改进交叉与变异算子。建立半刚性连接钢框架优化设计数学模型,编制了基于遗传算法的优化设计程序。运用这一优化算法可以直接从型钢截面表中选取截面,并在优化设计过程中考虑了连接可变性和二阶效应的影响。通过几个设计实例表明,考虑几何非线性会使用钢量增加,有支撑的情况下,半刚性连接较刚接用钢量经济。

Design of steel frames with semi-rigid connections based on a genetic algorithm

Steel frames with semi-rigid connections are optimized using a niche genetic algorithm(NGA).The limitation of GA such as poor local search ability and premature is largely enhanced.The crossover operator and mutation is improved while considering the adaptive method.Mathematic model of steel frames with semi-rigid connections is discussed.A software system is developed for steel frames with semi-rigid connections.The design algorithm obtains optimum frame by selecting appropriate sections from standard steel section tables,the algorithm accounts for the effect of the flexibility of the connections and the geometric non-linearity of the members,two design examples with semi-rigid connections are studied.The result has shown that consideration of geometric non-linearity results in more weights,it is also noticed that using steel weights is lighter to braced steel frame with semi-rigid connections.