曲线段有砟道床横向阻力分布及其影响研究

Research on the Distribution of Lateral Ballast Resistance in Curved Segments and Its Influence

研究目的:为确定曲线段道床横向阻力分布及其对无缝线路稳定性的影响,对某曲线半径为800 m的曲线线路开展道床横向阻力现场原位测试,测试直线、缓和曲线及圆曲线段的道床横向阻力。基于测试结果,建立直线-缓和曲线-圆曲线一体化无缝线路稳定性计算模型,分析缓和曲线段道床横向阻力分布对无缝线路稳定性的影响,从而为无缝线路设计提供指导。研究结论:(1)道床横向阻力测试中应避免反向顶推轨枕,以确保前后测试数据的一致性和重复性;(2)曲线段道床横向阻力存在显著差异,圆曲线中点、直线测点的道床横向阻力分别是缓和曲线中点阻力值的1.21倍、1.37倍;(3)缓和曲线段无缝线路的最小临界温升小于圆曲线段,并受缓和曲线段道床横向阻力分布的影响;(4)为避免缓和曲线段无缝线路先于圆曲线段线路发生失稳,确定了道床横向阻力不同分布下曲线半径300~1 000 m对应缓和曲线中点道床横向阻力最小值;(5)本研究成果可为无缝线路稳定性分析提供指导。

Research purposes:In order to determine the distribution of lateral ballast resistance in curved segments and its influence on stability of continuous welded rail(CWR),situ tests of lateral ballast resistance for the curve line with a curve radius of 800 m were carried out to get the lateral ballast resistance of sleepers in straight line(SL),transition curve(TC)and circular curve(CC).Based on the test results,a SL-TC-CC integrated model for analyzing the stability of CWR was established.With the model,the effects of the distribution of lateral ballast resistance in TC segment on the stability of CWR were analyzed,to provide guidance for the design of CWR.Research conclusions:(1)In lateral ballast resistance tests,reverse pushing sleepers should be avoided to ensure the data stay consistent during the whole test.(2)There is a significant difference in the lateral ballast resistance of sleepers of SL,TC and CC segment.The lateral ballast resistance at the midpoint of CC and the measure point of SL is 1.21 and 1.37 times larger than that at the midpoint of TC.(3)The minimum critical temperature rise of CWR in TC segment is smaller than that in CC,and it is influenced by the distribution of lateral ballast resistance in TC segment.(4)In order to avoid the instability of line in TC segment before that in CC,the minimum lateral ballast resistance at the midpoint of the TC of radius from 300 m to 1000 m under different distribution of lateral ballast resistance is determined.(5)The research results can provide reference for the stability analysis of CWR.