无缝线路稳定性分析有限元模型

利用有限元法建立包含钢轨、扣件、轨枕和道床阻力为一体的轨道框架模型。研究在温度力作用下无缝线路的臌曲失稳问题。推导相应的数值计算公式并编制了计算程序。轨道框架模型由4种单元组成：用考虑钢轨非线性变形的平面梁单元代表钢轨；无几何尺寸的两结点弹簧单元模拟钢轨扣件；弹性基础上的普通平面梁单元表示轨枕；弹簧单元模拟道床的横向、纵向阻力，并考虑了道床阻力的非线性特性。运用该模型，分析道床横向阻力、轨枕失效、曲线半径和线路初始弯曲对无缝线路稳定性的影响，得到不同工况下钢轨横向位移-温度曲线、钢轨内应力分布及钢轨和轨枕的横向变形分布曲线。

Finite Element Model for Analyzing the Stability of Continuously Welded Rail Track

Track panel model including rails, rail fastenings, cross ties and ballast resistances as a whole system is developed by means of finite element method for analyzing the buckling of continuously welded rail (CWR) track subjected to temperature stress. Based on the model, the numerical computational formulas are induced and programmed. The track panel model consists of four elements: a planar beam element considering the non-linear deformation behavior of rails to stand for the rail; an spring element with two nodes and zero length to simulate rail fastening; a normal planar beam element on elastic foundation to represent the tie; spring elements to simulate the lateral and longitudinal ballast resistances, taking into account the nonlinear peculiarity of the ballast resistance. Influences of the lateral resistance of ballast, invalid ties and curve radius as well as initial flexural deformations on the stability of CWR track are investigated. Different lateral displacement-temperature curves of the rail,distributions of the compressive force of the rail and lateral displacements of the rail and the tie along axial rail are presented.