Long-term monitored data are presented for a road section of the Qinghai-Tibet Highway before and after installing the TPCTs.

Cooling scope and period of the TPCTs are analyzed; cooling effects for the soil layers are examined.

Cooling performance of the TPCTs is discussed from the perspectives of embankment deformation and crack formation.

Some suggestions are proposed for a better design of the TPCTs in highway constructions in permafrost regions.