摘要
考虑扣件阻力、扣件阻矩、道床阻力及间隔铁阻力的非线性特性 ,建立了可动心轨无缝道岔钢轨温度力及位移的分析模型和计算方法 ,编制了计算分析软件。以秦沈客运专线 18号无缝道岔为例 ,分析了不同阻力参数的影响 ,所得结论对无缝道岔的设计和养护维修具有一定的指导意义。
Continuous welded turnouts are important for CWR track through the railway station.The turnouts at stations are welded with rails,which bring changes to the load and deformation of the turnouts,and further bring much more difficulties for the designing and maintaining of CWR track.The main purpose of the designing theory of welded turnouts is to calculate the expanding and contracting displacements of the inner rails,the additional temperature forces of the stock rails and the forces acted on spacer blocks,and to guarantee these values are within the allowable limits. Based on the finite element principle,a nonlinear calculating model of the continuous welded turnout with movable-point frog is proposed.According to the relations between temperature forces,resistances and displacements,the equilibrium equations can be obtained.The maximum influence distance of welded turnout is supposed to be 50 m in front and behind of the turnout.Beyond the influence range,the rails don′t expand or contract.In the initial condition,there isn′t temperature drop or rising,and the welded turnout is at the stress-free temperature.Newton iterative procedure is utilized to obtain the solution at each temperature change level. Some influences of different resistances of the CWR turnout are investigated.The additional temperature forces of the stock rails and the inner rail displacements will increase with the decrease of ballast resistance.The inner rail displacements and the shear forces acted on the bolts of spacer at heel will increase with the decrease of fastening resistance.The wing/frog rail displacement and the shear forces acted on the bolts of spacing iron block at the end of wing rail will increase with the decrease of torsional moment of spacing iron block.Thus in the maintenance of continuous welded turnouts,special attention should be paid to fullness and good quality of tamping of ballast,the tightness of fastenings and the sufficiency of the torsional moment of bolts.The inner rail displacement will increase with the increase of gap limit of spacer pieces at heel,and shear forces will increase with the decrease of that.In order to guarantee the displacements and shear forces don′t exceed the allowable limits,the gap limit of spacer pieces at heel should be appropriate.The results can be used to guide the structural design and the maintenance of continuous welded turnout.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2001年第1期84-91,共8页
China Railway Science
