摘要
温度荷载对无砟轨道结构服役过程中的受力变形有显著影响,研究桥上无砟轨道结构的温度特性,可以为轨道结构设计和服役性能分析提供温度荷载取值的理论依据。以东北严寒地区CRTSⅠ型板式无砟轨道-桥梁体系为研究对象,融合地理信息与气温变化模拟,通过气象大数据驱动的动态边界条件生成方式,建立考虑轨道东/西向非对称辐射特征的精细化温度场分析模型,分析桥上CRTSⅠ型板式无砟轨道结构的温度特性,重点研究轨道板和水泥沥青(CA)砂浆层的垂向温度梯度荷载,并与无砟轨道-路基结构温度场做对比,分析不同下部结构对轨道结构温荷载的影响。结果表明:采用的模拟方法可以为计算桥梁上轨道结构温度场提供一定的可靠性;经计算,东北地区的桥上无砟轨道结构轨道板全年的温度服役范围在-34~50℃,CA砂浆层为-23~35℃,底座板为-15~23℃;该地区桥上CRTSⅠ型无砟轨道轨道板和CA砂浆层的正温度梯度荷载处于0~93℃/m和0~275℃/m,负温度梯度荷载为-43~0℃/m和-170~0℃/m,CA砂浆层承受着更大的日温度梯度荷载的周期作用;与无砟轨道-路基结构相比,桥上无砟轨道结构产生的温度梯度更大,轨道板与CA砂浆层的最大正温度梯度分别增大约6%和16%,最大负温度梯度分别增大了约5%和32%。
The temperature load has a significant impact on the stress and deformation of bridge-mounted ballastless track structures during service.The temperature characteristics of ballastless track structures on bridges were investigated,which can provide theoretical basis for temperature load values in track structure design and service performance analysis.By examining the CRTSⅠslab ballastless track-bridge system in Northeast China's cold regions,a refined temperature field model was developed,integrating geographic information and temperature change simulation.Dynamic boundary conditions,driven by meteorological big data,were used to account for the east-west asymmetric radiation characteristics of the track.The temperature characteristics of the track slab and cement asphalt(CA)mortar layer,including vertical temperature gradient loads,were analyzed and compared with those of ballastless track-subgrade structures.The effect of different substructures on the temperature load of the track system was also explored.The results indicate that the simulation method used can provide reliable calculations for the temperature field of track structures on bridges.The overall temperature service range for the bridge's ballastless track slab is-34℃to 50℃,while the CA mortar layer ranges from-23℃to 35℃,and the base slab ranges from-15℃to 23℃.The positive temperature gradient loads for the bridge CRTSⅠballastless track slab and CA mortar layer are between 0 and 93℃/m and 0 and 275℃/m,respectively,while the negative gradient loads range from-43℃/m to 0℃/m and-170℃/m to 0℃/m.The CA mortar layer experiences larger cyclic daily temperature gradient loads.Compared to the ballastless track-subgrade structure,the bridge-mounted ballastless track structure exhibits greater temperature gradients,with the maximum positive temperature gradients for the track slab and CA mortar layer increasing by approximately 6%and 16%,respectively,while the maximum negative gradients increase by about 5%and 32%.
作者
赵丽华
王浩宇
梁浩
ZHAO Li-hua;WANG Hao-yu;LIANG Hao(School of Transportation Engineering,Dalian Jiaotong University,Dalian 116028,China;China Railway Fourth Survey and Design Institute,Wuhan 430000,China)
出处
《科学技术与工程》
北大核心
2025年第28期12253-12263,共11页
Science Technology and Engineering
基金
国家自然科学基金(52108402)
辽宁省教育厅科学研究支持项目(LJKMZ20220833)。
关键词
无砟轨道
热力学模型
温度场
温度梯度
ballastless track structure
thermodynamic model
temperature field
temperature gradient
