地铁列车制/启动运行对折返线道岔尖轨磨耗影响机制研究

Turnout blade wear of turn-back line exists obviously and expands rapidly, so it is one of important influences on impairing turnout normal service performance. Based on wheel-rail contact theory in non-steady state, studies on mechanism of the influences of subway train braking/starting running on turnout blade wear of turn-back line are carried out from the aspects of train running parameters at variable speed and turnout structure line type. The detailed contents include: the dynamic coupling model for subway train wheel set and turnout switch of turn-back line is established using contact finite element method, of which the wheel-rail contact relationship is considered as the non-hertz contact form including longitudinal large creep, and then combining with Archard model, the blade wear calculation model is built which is validated by comparing railhead profiles data of blade key cross-sections of typical turnouts in turn-back line from field test with the data from simulation calculation; using the transient dynamic method the influences of train braking/starting running accelerations and line types of the plane and vertical sections of turnout switch on blade wear are calculated and analyzed, and the influence mechanism of blade wear is clarified; considering the main influencing factors of blade wear, the speed-change control mode for subway train turn-back running and the line type matching relationship of the plane and vertical sections of turnout switch are optimized respectively to find out the measures of retarding blade wear. The research results can make progress in improving the structure design method of subway turnout in turn-back line, and provide scientific basis and technical guidance for the control of turnout blade wear.

折返线道岔尖轨磨耗情况突出且扩展迅速，是削弱道岔正常使用性能的重要因素之一。本项目基于轮轨非稳态接触理论，针对列车变速行车参数和道岔结构线型两方面，开展地铁列车制、启动运行对折返线道岔尖轨磨耗影响机制的研究。主要包括：利用接触有限元法建立地铁列车轮对与折返线道岔转辙器动力耦合模型，轮轨关系考虑为包含纵向大蠕滑的非赫兹接触形式，并以此为基础结合Archard模型建立尖轨磨耗计算模型，通过对比典型折返线道岔尖轨关键断面轨头廓形的测试及仿真结果，验证模型的正确性；采用瞬态动力学方法计算并分析列车制、启动运行加速度及转辙器平、纵断面线型对尖轨磨耗的影响，阐明尖轨磨耗影响机制；从影响尖轨磨耗的主要因素出发，分别对地铁列车折返运行变速控制方式及转辙器平、纵断面线型匹配关系进行优化，寻求减缓尖轨磨耗的措施。该研究成果可进一步完善地铁折返线道岔结构设计方法，为折返线道岔尖轨磨耗控制提供科学依据和技术指导。

项目针对地铁折返线道岔动力特性和尖轨磨耗状况展开研究，建立了能够描述道岔区轮轨复杂接触状态的车辆-道岔动力耦合模型，并以此为基础建立了道岔钢轨磨耗计算模型，利用现场监测数据验证了该模型的正确性。同时通过几何学手段推导了各类道岔尖轨切削方式的计算方法。采用所建立模型计算并分析了对应不同切削方式的地铁小号码道岔区域轮轨系统动力特性，进而研究了尖轨切削类型、道岔侧股曲线半径和列车运行速度等因素对尖轨磨耗发展的影响。归纳影响机制，从所得结论可知，道岔结构类型和列车运营参数均会对系统动力和磨耗状况产生不同程度的影响。对小号码道岔而言，半切线型和半割线型尖轨可为岔区带来良好的行车安全性和平稳性，同时轮轨间较小的相互作用能够保证结构使用稳定性和尖轨的抗磨耗性能。相离半切线型尖轨行车性能及使用特性虽较半切线型和半割线型尖轨有所降低，但考虑到此种切削方式将大大提高尖轨粗壮度，在满足列车运行要求的前提下显著增加了自身使用寿命，可作为小号码道岔尖轨主要切削类型之一。研究成果可为进一步认识地铁小号码道岔尖轨磨耗机制及结构选型起到一定的指导作用。