单元无砟道床温度场时空分布非均匀特征  

Temporal and Spatial Non-uniformity of Temperature Field of Unit Ballastless Track Bed

作　　者：刘钰 蒋典佑[1,2] 孙晓丹 赵国堂 LIU Yu;JIANG Dianyou;SUN Xiaodan;ZHAO Guotang(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Key Laboratory of High-speed Railway Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;China State Railway Group Co.,Ltd.,Beijing 100844)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031 [3]中国国家铁路集团有限公司,北京100844

出　　处：《铁道学报》2023年第8期118-128,共11页Journal of the China Railway Society

基　　金：国家自然科学基金(51708459);四川省自然科学基金(2023NSFSC0388)。

摘　　要：无砟道床温度场是无砟道床温度效应的控制因素。基于传热学原理和实时阴影技术,构建CRTSⅡ型板式无砟轨道单元结构温度场计算模型,研究持续高温环境下温度场的时、空分布特征及在短时气温骤变作用下的演变规律。研究表明:无砟道床的温度和温度梯度以天为单位周期性变化。三天持续高温环境下,无砟道床温度逐步上升,温度梯度逐步下降。短时气温骤变引起温度梯度快速变化,但其影响会在次日清晨消失。短时气温骤升使温度梯度明显升高,但在骤变次日之后温度梯度反而低于原气温情况;短时气温骤降的影响趋势恰好相反。任意时刻,温度场沿水平和深度方向均呈强烈非均匀性。水平方向,正温度梯度时,太阳辐射起主导,阳面温度显著高于阴面,板端高于板中,板角最高;负温度梯度时,对流换热起主导,温度双向对称分布,板中高于板端,板角最低。深度方向,温度非线性变化,轨道板内尤为显著;同一深度,板中心点对气温骤变最不敏感,板角敏感性大于板端。The temperature field of ballastless track bed is the controlling factor for the temperature effect of ballastless track bed.Based on the principle of heat transfer and real-time shadow technology,a numerical model of the unit structure of CRTSII slab ballastless track was established for the temperature field calculation,to study the temporal and spatial distribution characteristics of the temperature field under continuous high temperature environment and the effects of sudden temperature changes on the temperature field.The results show that both the temperature and temperature gradient of the ballastless track bed vary periodically in units of days.During three days of continuous high temperature,the temperature of the track bed gradually increases whereas the temperature gradient gradually decreases.Sudden temperature change causes rapid response of temperature gradient,but the response will not disappear till the early morning of the next day.A sudden temperature rise causes a remarkable increase in the temperature gradient,but from the next day of the sudden temperature change,the temperature gradient will be lower than that without sudden temperature change.By contrast,the effect of sudden temperature drop shows an opposite trend.At any time,the temperature field shows strong non-uniformity along the horizontal and depth directions.In the horizontal direction,for a positive temperature gradient,the solar radiation dominates the temperature field,exhibiting a significantly higher temperature in the sunny side than that in the shady side,with higher temperature at the slab end than that in the slab center and the highest value at the slab corner.For a negative temperature gradient,the convective heat transfer is the dominant factor,which leads to a symmetrical distribution of temperature in both longitudinal and transverse directions,with higher temperature at the slab center than that in the slab end and the lowest value at the slab corner.Along the depth direction,the temperature changes nonlinearly,espec

关 键 词：板式无砟轨道 单元结构 温度场 时空非均匀 气温骤变 

分 类 号：U213.244[交通运输工程—道路与铁道工程]