基于满应变准则的大规模桁架结构的最小柔度设计

Minimum Flexibility Design of Large Truss Structure Based on Full Strain Criteria

针对大规模桁架结构,推导出一种结构优化设计方法。其设计目标为整个结构的柔度最小,也即刚度最大;采用的力学准则为满应变设计准则;在整个桁架结构重量满足一定约束的前提下,通过优化各杆件截面积,达到整体柔度最小。仿真结果表明,该方法可以在有限迭代步数下实现桁架结构总体柔度最小。将两次迭代所有杆截面积之差总和作为停机准则,随着停机准则的减小,整个计算所用迭代次数逐渐增大,所需计算时间也逐渐增长。在实际应用中,应根据实际需求和成本限制综合确定停机准则。

For the large truss structure, this paper derived a structure optimization method. The design goal is the minimum flexibility or maximum stiffness, and the mechanical standards is full strain criteria. Under the premise of the weight of the entire truss structure satisfying certain constraints, it achieved the minimum flexibility by optimizing the cross-sectional area of the bar. Simulation results show that the method can achieve the smallest overall flexibility of truss structure under a limited number of iterations. It took the sum of two iterations of all bar cross-sectional area difference as the stopping criterion, with the decrease of stopping criterion, the number of iterations used in the calculation increases, and the computation time also gradually increase. In practical applications, we should determine stopping criteria based on the actual demand and cost constraints.