基于遗传算法的钢-竹组合工字形梁截面优化设计  

Multi-objective optimal section design of I-shaped section steel-bamboo composite beam using genetic algorithm

作　　者：邬沛 李玉顺[1] 许达 卞西波 WU Pei;LI Yushun;XU Da;BIAN Xibo(School of Civil and Environmental Engineering,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学土木与环境工程学院

出　　处：《建筑结构学报》2020年第1期149-155,共7页Journal of Building Structures

基　　金：国家重点研发计划(2017YFC0703502);国家自然科学基金项目(51678310,51978345)

摘　　要：以钢-竹组合构件的计算理论与设计方法为研究背景,结合结构优化设计的相关理论对钢-竹组合工字形截面梁进行优化设计。此次优化有成本最小化和抗弯刚度最大化两个目标,采用加权系数法将两个目标转化为单一优化目标,并加以承载力和构造要求的约束条件,最终建立钢-竹组合工字形截面梁多目标优化设计的数学模型。利用遗传算法搜索得到设计参数的最优解,对组合梁的含钢率、翼缘宽厚比和腹板高厚比随加权系数变化的规律及其取值进行分析研究。优化结果表明:采用遗传算法进行优化后的钢-竹组合工字形截面梁的截面参数取值合理,其中组合梁的含钢率范围在9%~20%之间;翼缘宽厚比取5左右为宜;腹板高厚比的取值不小于10且不大于40,同时高厚比随着组合梁跨度的增加逐渐减小,其中跨度较小时取30左右,跨度较大时约取15。优化设计实例表明了所采用的优化思路和优化方法对钢-竹组合工字形梁截面的优化是有效可行的。Based on the calculation theory and design method of steel-bamboo composite members,this paper focused on the optimization of steel-bambo composite I-shaped beam combined with relative structural optimization design theory.The weighting coefficient method was used to find the balance between the two optimization targets,the minimization of cost and the maximization of flexural stiffness,based on the constraints of bearing capacity and construction requirements.Finally,a mathematical model of multi-objective optimal design of steel-bamboo composite I-shaped beam was established.The optimal solution of the design parameters was obtained by using genetic algorithm(GA).The steel ratio,width to thickness ratio of flange and height to thickness ratio of web were analyzed and corresponding reference values for component design were presented.The GA based optimization shows the reasonable sectional parameters of composite beam that the steel ratio ranges between 9%~20%and the appropriate width to thickness ratio of the section flange is 5.The height to thickness ratio of web decreases with the increasing span,which ranges from 10 to 40.And the height to thickness ratio is about 30 when the span is small,and is about 15 with large span.The case study shows that the optimization method in this paper is effective and feasible for the design of steelbamboo composite I-shaped beam.

关 键 词：钢-竹组合工字形截面梁 多目标优化设计 遗传算法 加权系数法 截面参数 

分 类 号：TU398.9[建筑科学—结构工程] TU318.1