时速160 km城市轨道交通内置式泵房板式道床动力特性分析

北京轨道交通新机场线在部分区间隧道的最低点设置了内置式泵房板式道床。为了保证时速160 km市域列车在动荷载作用下轨道结构的安全性和可靠性,建立了车辆-轨道-隧道三维耦合动力分析模型,计算分析100~220 km/h共7种行车速度下内置式泵房板式道床的动力特性。提取道床振动评价指标(垂向位移、垂向加速度)、道床强度评价指标(纵横向拉应力)、行车平稳性评价指标(车体垂向、横向加速度)和行车安全性评价指标(轮轨垂向力、轮轨横向力、脱轨系数、轮重减载率)与规范允许值进行对比。计算结果表明,各动力学评价指标均随行车速度的增大而增加,各动力学评价指标均在规范允许值之内,并且有较大的安全余量。

Dynamic Characteristics Analysis on Slab Ballastless Track for Internal Type Pump House in 160 km/h Speed Urban Rail Transit

Beijing New Airport Line has set several internal type pump houses at the lowest point of partial tunnel sections to reduce the construction risk of"freezing method"used in traditional wastewater pumping house,while saving engineering investment and speeding up construction progress.The track structure of internal type pump house has been specially designed.The slab ballastless track is applied for the first time in domestic urban rail transit to improve the smoothness,stability and durability of track structure.In order to ensure the safety and reliability of the track structure under the dynamic train load at the speed of 160 km/h,a three-dimensional coupled dynamic analysis model of vehicle-track-tunnel was established in this paper,to analyze the dynamic characteristics of the slab ballastless track for internal type pump house under 7 kinds of driving speeds ranging of 100-220 km/h,and evaluate the stability and safety of the train operation at the same time.Calculation results show that the dynamic evaluation indexes increase with the promotion of the train speed,and the dynamic indexes all reach the maximum at the speed of 220 km/h.Each dynamic evaluation index is under the allowable value of the specification,and there is still a large safety margin from the allowable value of the specification.