Finite Element Analysis On The Stability Of Continuously Welded Rail Track

At first, the subject about the stability of continuously welded rail track is presented in the article In retrospect, different relevant researchers at home and abroad are presented, with the calculative model of finite element given The numerical computational formulas are induced and programmed Then various effects on the stability of continuously welded rail track are analysed Finally ,the subject about the stability of continuously welded rail track is summarized ,(1) The finite element model is a track panel including rails, ties, rail fastenings and ballast resistances as a whole system The non-linear beam element with 6 degrees of freedom represents the rail, whose stiffness matrix consists of the standard linear stiffness matrix of the beam element and the non-linear stiffness matrix associating with displacements An spring element with two nodes and zero length stands for pad-fastening system A beam element on elastic foundation simulates tie, whose stiffness matrix is the standard linear stiffness matrix of the beam element The boundary spring simulates the lateral and axial as well as torsional ballast resistances(2) In order to obtain the complete bucking curve of the CWR track during temperature increasing, the increment technique should be used to solve the finite elementequation(_|Kâ–³a_m = â–³-|Q_m ) in numerical computation process Where -|K is the totalstiffness matrix, which could be obtained by assembling beam element for rail, beam element for tie, spring element for rail fastening and boundary spring element for ballast resistance Twice calculations have to be performed in each load increment step, in which the first step is linear analysis, the second is non-linear analysis , The curves of the displacements a_m and the temperature increment T is formed through step by stepcalculations When the maximum displacement exceeds the specified tolerance, the CWR track will be in state of instability ,(3) Based on the finite element theory, the associated program is compiled, with which influences of the lateral rigidity of rail , cross sectional area of rail ,lateral and torsion resistances of rail fastenings, different ballast states, invalid ties and curve radius as well as initial flexural deformations on the stability of continuously welded rail track are discussed ? The distributions of the displacements and the stresses of the rail along axial rail is presented o(4) The results show that the lateral rigidity of rail, the torsional resistance of rail fastenings , the lateral resistance of rail fastenings and ballast make for the stability of the CWR track a The initial flexural deformations make against the stability of the CWR track ? The lateral resistance of ballast as well as the initial flexural deformations are notable in these influences ? So, maintainance should be emphasized on the ballast tightness, with the examination on the initial flexural deformations with the CWR track laying and maintainingo...