变截面高层筒体结构的有限元线法整体稳定和二阶分析

Overall stability and second-order analyses of tall building tubular structures with stepped cross-sections by FEMOL

本文用有限元线法对变截面的高层简体结构进行空间整体稳定和二阶分析。先把实际框筒结构分段连续化为正交各向异性折板结构；用有限元线法，通过有限条元半离散化，取结线上位移为基本未知函数，由势能驻值原理建立稳定和二阶分析的常微分方程组；由常微分方程求解器直接求解。

In this paper,overall stability and second-order analyses of tall building tubular struc-tures with stepped cross-sections by use of the Finite Element Method of Lines(FEMOL)are presented.The framed tubes are firstly replaced by equivalent orthotropic continua.Then the continuum models are analyzed by applying FEMOL,in which the nodal displace-ments are taken as primary unknown functions. The Minimum Potential Energy Principlesare used to set up the Ordinary Differential Equtations(ODE)of overall stability and sec-ond-order analyses.The ODEs are directly solved by ODE Solver,which is a general pur-pose program developed for solving various ODE,Then the stability critical loads and thesecond-order displacement and internal forces can be obtained.