坡度对长大坡道桥上无缝道岔的影响分析

为探讨制动工况下,坡度对长大坡道桥上无缝道岔受力与变形的影响,以国内某一坡度为17.2‰新建铁路线上的桥上无缝道岔为例建立力学分析模型,运用"等效轮轨黏着系数",建立了有砟轨道"岔-桥-墩"相互作用的一体化模型,分析不同坡度下列车制动时,钢轨纵向力、钢轨位移、墩台纵向力、心轨和尖轨位移以及间隔铁纵向力的变化。分析结果表明:坡度的增大对桥上无缝道岔的受力与变形都是不利的;侧股间隔铁的纵向力比直股间隔铁小,但是其受坡度的影响却较大;长大坡道上容易产生爬行现象,应加强无缝道岔防爬锁定,并加密防爬观测次数。

Influence of Slope Gradient on Gapless Turnout upon Bridge with Long Heavy Grade

To investigate the influence of slope gradient on the stress state and on the deformation behavior of gapless turnout which is laid upon a bridge with long heavy grade under brake operation condition,the paper took a domestic gapless turnout upon a bride of a newly-built railway with a slope gradient of 17.2‰ as an example,established the integrated interaction model of "turnout-bridge-pier" by using "equivalent wheel-rail adhesion coefficient",and analyzed the changes of rail longitudinal force,rail displacement,pier and abutment longitudinal forces,frog rail and switch rail displacements,and the longitudinal force of the spacing block.The results show that: the increase of slope gradient is bad for both the stress state and deformation behavior of gapless turnout upon bridge.The longitudinal force of the spacing block of branch lines is smaller than that of main lines,but suffering with the larger influence of the slope gradient.Track creeping is most likely to occur in the long heavy grade,so it is necessary to strengthen anti-creeping locking of gapless turnout,and to increase the observation frequency of anti-creeping.