Cooling Effect Analysis of Heat Pipe Subgrade of Qinghai-Tibet Highway in Permafrost Areas

Subgrade failure of Qinghai-Tibet Highway in permafrost areas is an important issue that constrains highway development in Qinghai-Tibet region.Heat pipe is an effective measure to avoid settlement of the upper limit of permafrost subgrade.In order to research the cooling effect of heat pipe subgrade,the temperature of one-hundred-meter-long subgrade test section in Wudaoliang of Qinghai-Tibet Plateau was monitored dynamically.Through comparison with the common subgrade,the cooling effect of heat pipe subgrade in permafrost areas was analyzed.It is founded that heat pipe subgrade can effectively reduce subgrade temperature,protect permafrost and strengthen subgrade thermal stability.