梁柱简化模型在自立塔塔线体系动态响应中的适用性研究

Applicability of simplified beam model of the dynamic response of the tower line system

对输电塔进行合理简化可以提高塔线体系动力学仿真的效率。本文给出自立塔梁柱简化模型的计算方法,并提出利用梁柱简化模型计算方法建立自立塔塔线体系整体模型,同时采用桁梁混合模型建立精细化塔线体系整体模型,对两种模型塔线体系静力特性及振型和固有频率等动力特性进行对比分析。以脱冰工况为例,采用生死单元技术将施加在输电线节点上的集中质量单元杀死来模拟脱冰,实现对塔线体系动力学响应的有限元模拟,研究塔线体系简化模型在动态响应中的适用性。结果表明,两种模型弯曲变形误差小,低阶的振型相同,固有频率值误差小,动力特性基本相同;脱冰工况下,自立塔节点位移和塔材内力时程曲线一致,在提高计算效率的情况下,能有效保证计算精度。

Reasonable simplification of the transmission tower can improve the efficiency of the dynamic simulation of the tower line system.This paper presents the calculation method of the simplified model of the beam and column of the self-standing tower,and proposes to use the calculation method of the simplified model of the beam and column to establish the overall model of the tower-line system of the self-supporting tower.At the same time,a truss beam hybrid model is used to establish a refined tower line system model.The static characteristics of the two model tower line systems and the dynamic characteristics such as vibration modes and natural frequencies are compared and analyzed.Taking the de-icing condition as an example,the life-and-death unit technology is used to kill the concentrated mass unit applied to the power line node to simulate de-icing,to realize the finite element simulation of the dynamic response of the tower line system,The results show that the bending deformation error of the two models is small,the low-order vibration modes are the same,the natural frequency value error is small,and the dynamic characteristics are basically the same.Under the de-icing condition,the self-supporting tower node displacement and the tower internal force time-course curve are consistent.It can effectively guarantee the calculation accuracy while improving the calculation efficiency.