有轨电车嵌入式轨道路基不均匀沉降限值研究  

Study on the Threshold Value of Uneven Settlement of Subgrade under Embedded Rail Track of Tram

作　　者：孙魁 农兴中 肖军华[2] 冯青松[3] 翟利华 SUN Kui;NONG Xingzhong;XIAO Junhua;FENG Qingsong;ZHAI Lihua(Guangzhou Metro Design and Research Institute Co.,Ltd.,Guangzhou 510010,China;The Key Laboratory of Road and Traffic Engineering,Ministry of Education,Tongji University,Shanghai 201804,China;State Key Laboratory of Performance Monitoring Protecting of Rail Transit Infrastructure,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]广州地铁设计研究院股份有限公司,广州510010 [2]同济大学道路与交通工程教育部重点实验室,上海201804 [3]华东交通大学轨道交通基础设施性能监测与保障国家重点实验室,南昌330013

出　　处：《铁道标准设计》2024年第6期51-57,共7页Railway Standard Design

基　　金：国家自然科学基金项目(51878277);广东省城市轨道交通工程建造新技术企业重点实验室课题(51678447)。

摘　　要：为确定有轨电车嵌入式轨道路基不均匀沉降的具体限值,根据多刚体动力学和有限单元法,建立考虑路基不均匀沉降的有轨电车车辆-嵌入式轨道-路基耦合动力学模型。详细分析在自重荷载作用下路基沉降幅值和波长对嵌入式轨道几何形态的影响规律,识别出对车辆和轨道结构动力响应较为敏感的路基沉降波长,并基于轨道板疲劳寿命得到路基不均匀沉降限值。研究结果表明:(1)在自重荷载作用下,余弦形路基不均匀沉降区域内钢轨的跟随性变形曲线也呈现为类余弦形,与普通扣件离散支承式无砟轨道的钢轨变形曲线基本相同;(2)随着沉降波长增加,车体垂向加速度和嵌入式轨道结构的动力响应均呈现先增加后减小的变化趋势;当路基沉降波长取10 m时,车体垂向加速度、钢轨动位移、轨道板动位移和轨道板弯曲应力都取得最大值,从而说明敏感路基沉降波长为10 m;(3)为保证有轨电车嵌入式轨道的60年服役年限,建议严格控制波长10 m以下的路基不均匀沉降,波长为20 m路基不均匀沉降对应的沉降幅值不应大于24 mm。In order to determine the specific threshold value of uneven settlement of subgrade under embedded rail track of tram,a coupled dynamic model of tram-embedded rail track-subgrade considering uneven settlement of subgrade is proposed according to the multi-rigid body dynamics and finite element method.The influence of subgrade settlement amplitude and wavelength on the geometry of embedded rail track under self weight load is investigated in detail.And the subgrade settlement wavelength that is sensitive to the dynamic responses of tram vehicle and track structure is identified.Then the threshold value of uneven settlement of subgrade is obtained on the basis of the fatigue life of track slab.The results show that,under the action of self-weight load,the following deformation curve of rail in the area of uneven settlement of cosine subgrade also presents cosine-like shape,which is basically the same as that of ballastless track supported by ordinary fasteners.Secondly,with the increase of the settlement wavelength,the vertical acceleration of the car body and the dynamic responses of the embedded rail track show a trend of first increasing and then decreasing.When the subgrade settlement wavelength is 10 m,the vertical acceleration of the car body,the dynamic displacement of the rail,the dynamic displacement of the track slab and the bending stress of the track slab all get the maximum value,which indicates that the sensitive subgrade settlement wavelength is 10 m.Finally,in order to ensure the 60-year service life of the embedded rail track of tram,it is recommended to strictly control the differential settlement of subgrade with wavelength below 10m,and the corresponding settlement amplitude of differential settlement of subgrade with wavelength of 20m shall not be greater than 24 mm.

关 键 词：有轨电车 嵌入式轨道 路基不均匀沉降 轨道几何形态 疲劳寿命 

分 类 号：U216.3[交通运输工程—道路与铁道工程] U213.2