季节性冻土环境下有轨电车运营期轨道动力响应  

Dynamic responses of tram track during operation period in seasonal frozen soil area

作　　者：张中杰 李心熙 吴航 陈加核 禹海涛[2] ZHANG Zhongjie;LI Xinxi;WU Hang;CHEN Jiahe;YU Haitao(Shanghai Urban Construction Design&Research Institute,Shanghai 200125,China;Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]上海市城市建设设计研究总院(集团)有限公司,上海200125 [2]同济大学地下建筑与工程系,上海200092

出　　处：《隧道与地下工程灾害防治》2022年第1期48-54,共7页Hazard Control in Tunnelling and Underground Engineering

基　　金：国家自然科学基金资助项目(41922059,42177134)。

摘　　要：为保障冻胀土地基条件下有轨电车运营期安全,需研究列车移动荷载作用下季节性冻土环境下有轨电车轨道的动力响应。依托张家口崇礼奥运赛区有轨电车项目,选取典型黑色黏土为代表性冻胀土体,重点测试了温度变化时该土体的水力特性及力学行为;将有轨电车轨道简化为无限长均质直梁,将地层考虑为Pasternak双参数地基,基于Euler-Bernoulli梁理论推导列车荷载作用下轨道动力响应的解析表达式,通过参数化分析研究土体冻融行为对轨道动力响应的影响规律。结果表明:季节性冻融行为会对有轨电车动力响应产生影响,且随着地基土温度的升高,土层动刚度系数会逐渐降低,轨道的动力响应趋于放大。Attention should be paid to the dynamic response of railway track in seasonally frozen environment under moving tram loads in order to ensure the safety of tram during operation period. The black clay in Zhangjiakou was selected as the typical frozen soil sample, and the hydraulic and mechanical properties of the sample were tested under the environment of temperature variation. The long lined track of the tram was assumed as an infinite homogeneous beam resting on a Pasternak foundation, and the analytical solution for long lined tracks subjected to moving traffic loads was obtained based on the beam-elastic foundation theory. Parametric analyses were performed to investigate the influence of the freeze-thaw behaviors of soil on the dynamic response of railway subgrade. Results showed that the dynamic response of subgrade was affected by the freeze-thaw behaviors of soil, and the dynamic stiffness of foundation would decrease with the increase of temperature, and thus contributed to the amplification of dynamic responses of the track.

关 键 词：季节性冻土 列车荷载 轨道响应 解析解 

分 类 号：TU92[建筑科学—建筑设计及理论]