Under the condition of warming and wetting trend on Qinghai-Tibet Plateau due to climate change, summer rainfall infiltration alters the change of the hydrothermal state and may impact the cooling performance of crushed-rock interlayer embankment. Herein, two experimental models with the 1.4-m-thickness (M1) and 0.6-m-thickness (M2) crushed-rock layer (CRL) were conducted in an environmental simulator experiencing the freezing and thawing cycles. The hydrothermal response to rainfall events was investigated and quantified by analyzing the variations of measured soil temperatures, volumetric water contents, and heat fluxes. Thermal observations show that rainfall infiltration caused heat advection and resulted in step change of soil temperature at depth. Rainfall infiltration reduced the surface temperature of the CRL, but warmed the soil layer at depth by up to 2.13 °C. The average temperature of the base soil layer under the action of concentrated rainfall basically showed an increasing trend. In particular, the CRL with a smaller thickness (M2) had a more significant thermal response to rainfall event. In addition, the moisture pulse, experiencing a step increase and following a gradual decrease caused by rainfall water infiltration, appeared several hours earlier than the temperature pulse. Moreover, infiltrated water produced an additional energy to warm the soil at depth, with maximum heat flux of 12.13 W/m² and 79.90 W/m² for the M1 and M2, respectively. The infiltrated water accumulated at the top of base soil significantly delayed the refreezing processes in cold period due to the latent heat effect. The net founding of this study provide an insight into improving the design crushed-rock embankment in permafrost regions.

在气候变化导致青藏高原变暖和湿润趋势的情况下，夏季降雨入渗改变了热液状态的变化，并可能影响碎石夹层路堤的冷却性能。在此，在经历冻融循环的环境模拟器中进行了 1.4 米厚 (M1) 和 0.6 米厚 (M2) 碎石层 (CRL) 的两个实验模型。通过分析测量的土壤温度、体积含水量和热通量的变化，研究和量化了对降雨事件的水热响应。热观测表明，降雨入渗引起热平流，并导致土壤温度在深度处发生阶跃变化。降雨入渗降低了 CRL 的表面温度，但使深层土壤层升温高达 2.13 °C。集中降雨作用下基土层平均温度基本呈上升趋势。特别是，具有较小厚度（M2）的 CRL 对降雨事件具有更显着的热响应。此外，由于降雨入渗，水分脉冲出现阶跃增加并逐渐减少，比温度脉冲早几个小时出现。此外，渗入的水产生了额外的能量来加热深层土壤，最大热通量为 12.13 W/m 厚度较小（M2）的 CRL 对降雨事件的热响应更显着。此外，由于降雨入渗，水分脉冲出现阶跃增加并逐渐减少，比温度脉冲早几个小时出现。此外，渗入的水产生了额外的能量来加热深层土壤，最大热通量为 12.13 W/m 厚度较小（M2）的 CRL 对降雨事件的热响应更显着。此外，由于降雨入渗，水分脉冲出现阶跃增加并逐渐减少，比温度脉冲早几个小时出现。此外，渗入的水产生了额外的能量来加热深层土壤，最大热通量为 12.13 W/mM1 和 M2 分别为²和 79.90 W/m ^{2 。}由于潜热效应，积聚在基土顶部的入渗水显着延迟了寒冷期的再冻结过程。这项研究的建立为改进永久冻土区碎石路堤的设计提供了见解。