摘要
位于东北严寒地区的桥上无砟轨道结构,因服役区域气候条件的特殊性,导致温度荷载作用成为影响该地区轨道结构安全性和稳定性的主要因素。通过有限元软件建立桥上无砟轨道模型,基于东北地区气候条件,研究严寒地区桥上无砟轨道结构温度特性,分析温度梯度荷载作用范围,对该地区开展桥上无砟轨道结构设计、养护、维修作业具有重要理论价值。研究表明:桥上无砟轨道结构的整体温度随日气温呈正弦函数周期性变化,沿深度方向呈非线性分布,在0~0.2 m深度范围内,日温度变化幅度较大,在CA砂浆层温度分布曲线出现明显转折,表明CA砂浆层具有良好的隔热作用;东北严寒地区无砟轨道结构的整体服役温度范围为51~-13℃;综合近十年东北地区极端气象条件,计算获得该地区桥上无砟轨道结构轨道板的最大垂向正温度梯度为94.2℃/m,最大垂向负温度梯度为-55.8℃/m,均出现在春季;通过极端工况假定的结果,东北严寒地区桥上无砟轨道结构最大正温度梯度接近115℃/m,负温度梯度接近-60℃/m,建议轨道板服役性能分析时采用上述荷载进行检算。
Due to the special climate conditions in the severe cold region of Northeast China,temperature load has become the primary factor affecting the safety and stability of ballastless track structures on bridges.A model of the ballastless track on bridges was established using finite element software.Based on the climate conditions of Northeast China,the temperature characteristics of the ballastless track structure on bridges in severe cold regions were investigated,and the range of temperature gradient loads was analyzed.This study has important theoretical value for the design,maintenance,and repair operations of ballastless track structures on bridges in this region.The results showed that the overall temperature of the ballastless track structure on the bridge varied periodically with the daily air temperature following a sinusoidal function and exhibited a nonlinear distribution along the depth direction.Within the depth range of 0~0.2 m,the amplitude of daily temperature change was large,and a distinct inflection point appeared in the temperature distribution curve at the CA mortar layer,indicating that the CA mortar layer had good thermal insulation performance.The overall service temperature range for the ballastless track structure in the severe cold areas of Northeast China was 51℃ to -13℃.Based on the extreme meteorological conditions in Northeast China over the past decade,the maximum vertical positive temperature gradient of the track slab on the bridge in this area was calculated to be 94.2℃/m,and the maximum vertical negative temperature gradient was -55.8℃/m,both occurring in spring.Based on the results from an assumed extreme condition,the maximum positive temperature gradient for the ballastless track structure on bridges in the severe cold region of Northeast China was close to 115℃/m,and the negative temperature gradient was close to-60℃/m.It was recommended to adopt these load values for verification in the service performance analysis of the track slab.
作者
赵丽华
何花
胡安泽
ZHAO Lihua;HE Hua;HU Anze(School of Civil Engineering,Dalian Jiaotong University,Dalian 116028,China;Shandong Expressway Zibo Development Co.,Ltd.,Zibo 255000,China)
出处
《铁道标准设计》
北大核心
2025年第12期60-67,共8页
Railway Standard Design
基金
国家自然科学基金项目(52108402)
辽宁省教育厅科学研究支持项目(LJKMZ20220833)。
关键词
无砟轨道
东北严寒地区
极端气候
温度特性
温度梯度
ballastless track
severe cold region of Northeast China
extreme climate
temperature characteristics
temperature gradient
