高速铁路无砟轨道温度场简化计算方法

Simplified calculation of temperature field in high-speed railway ballastless track structure

为了计算高速铁路无砟轨道结构的温度场,根据热工学原理和简化的气象边界条件,建立求解曝露于大气环境下的高速铁路无砟轨道结构温度场方程.利用在京沪高速铁路CRTS-II型无砟轨道结构现场实测的温度分布数据对解得的温度场方程进行验证,并分析无砟轨道结构温度场的分布规律.结果表明：基于温度场方程的无砟轨道结构温度计算数据与其现场实测数据的分布规律基本一致;无砟轨道结构内部温度分布受到的外界环境影响在距其表面0-0.2m内非常明显,在0.2-0.4m内影响比较一般,而大于0.4m时影响比较微弱;轨道结构最大正温度梯度受其厚度的影响明显,在其上部0-0.2m内的最大正温度梯度出现时段一般为13：00-15：00,不同季节中夏季的最大正温度梯度最大、冬季最小.

A simplified temperature field equation was derived from the thermal transmission theory and the simplified meteorological boundary condition to calculate the temperature distribution in high-speed railway ballastless track structure（BTS）exposed to a periodic atmospheric environment.The measured temperatures of CRTS-II BTS in Beijing-Shanghai high-speed railway were used to validate the derived temperature field equation.Validation results showed that the calculated temperature distribution based on the derived equation was generally consistent with the measured one.Analysis of temperature distribution revealed that it was distinctly affected by the atmospheric environment,especially in depth 0-0.2 mof BTS.The daily maximum value of positive temperature gradient appeared at 1：00-3：00pm and it is obviously affected by the thickness of BTS.The maximum value of positive temperature gradient varies with seasons,being largest in summer and least in winter.