基于节点构形度均衡化的单层网壳结构优化设计研究

STUDY ON THE OPTIMIZATION DESIGN OF SINGLE-LAYER RETICULATED SHELL BASED ON THE HOMOGENIZATION OF NODAL WELL-FORMEDNESS

为实现网壳结构节点连接能力的均衡分布,改善结构性能,提升其极限承载力。基于构形易损性理论建立了衡量结构节点构形度差异性的评价指标,用以评价结构节点连接性能的差异性。在此基础上,将构件截面尺寸作为优化变量,以节点构形度差异系数最小化为优化目标,并考虑结构位移、构件长细比、强度及稳定性等约束条件,采用粒子群算法优化结构构件的截面尺寸。结果表明,节点构形度差异系数能准确反映网壳节点连接性能的差异性,通过粒子群算法优化结构构件的截面尺寸,可实现结构节点连接性能的均衡分布,改善结构在地震作用下的倒塌模式,有效提升了结构的整体性能。

In order to achieve a uniform distribution of nodal connection capacity of reticulated shell structures,to improve structural performance,and to enhance its ultimate bearing capacity,an index was proposed to measure the difference of the well-formedness between the structural nodes based on the structure vulnerability theory.Then the particle swarm optimization method(PSO)was used to optimize the cross-section size of structural members,in which the minimization of the difference between nodal well-formedness of structural nodes was taken as the optimization objective.In the optimization,constrains were considered such as the structural maximum displacement,the member slenderness ratio,the strength,and the stability of members.The results show that the defined difference coefficient of the structural nodal well-formedness can accurately reflect the uniformity of the overall stiffness of the structure.The uniform distribution of nodal connection performance can be realized by reducing the difference of the well-formedness of the structural nodes with the particle swarm optimization method to optimize the cross-section size of the structural members,the overall performance of the structure would be improved,and the failure model of the structure under earthquake has turn into the ductile failure mode.