【摘要】 将遗传算法和模拟退火算法相结合,以遗传算法作为基础,将模拟退火机制融入其中,提出遗传-模拟退火算法(GASA)。通过三个经典函数最小值求解,表明混合算法在优化行为、优化效率及稳定性方面均具有明显优势。以构件截面为优化变量,应用构形易损性理论,以结构集簇过程中自由簇构形度Q标准差最小为优化目标,建立单层球面网壳结构倒塌破坏模式优化模型。以一个原型跨度75 m、相似比1∶10的单层球壳振动台试验模型为例,采用GASA算法对此试验模型进行倒塌模式优化分析,通过优化前后自由簇构形度变化规律和加速度时程分析结果的对比,表明提出的优化方法及优化模型能够实现单层球面网壳在地震作用下的倒塌模式从无征兆的动力失稳破坏转化为承载力强度破坏。更多还原

【Abstract】 A genetic-simulated annealing algorithm(GASA) is proposed by combining genetic algorithm with simulated annealing algorithm in this paper.The combined algorithm takes genetic algorithm as the main process and integrates with simulated annealing mechanism.Firstly,by solving the minimum values of three classical functions,it was demonstrated the obvious advantages of the combined algorithm in optimization behavior,optimization efficiency and stability.Secondly,using the frame sections as the optimization variables and the minimum standard deviation of the well-formedness Q of free clusters in the clustering process as the optimization object,a collapse mode optimization model for the single-layer latticed shell was established based on the form vulnerability theory.Finally,taking an example of a shaking table test model of a single-layer spherical shell which had a 1∶ 10 similitude ratio and originated from a prototype of 75 m span,the collapse mode optimization was carried out with GASA algorithm.By comparison of the change rule of Q of free clusters and the results of time history analysis,it is shown that the optimization results by the optimization method and the optimization model can transform the collapse scenario of single-layer spherical shells under earthquake excitations from dynamic instability with no obvious signs to strength failure.更多还原