Analysis of temperature controlled ventilated embankment

A temperature controlled ventilated embankment (TCVE) of roads or railroads is proposed as an attractive engineering approach in permafrost regions. Comparing the measuring results in ventilated embankment (VE) with same conditions, which nearby TCVE testing fields, we demonstrate that in two testing fields with 30-cm and 40-cm diameter controlled vent ducts, the permafrost table raised by 0.3 m and 0.7 m, respectively. The average temperatures at the bottom of vent ducts decreased by 1.11 °C and 1.52 °C, respectively. The corresponding decrease at the bottom of the embankment was 0.5 °C and 0.7 °C. Compared to VE, the thawing period was cut down nearly 20 days and the time, during which heat was lost by embankment, was prolonged by more than a month. The heat flux into the permafrost beneath the embankment was reduced by nearly 1/4 in the filed with the 30-cm ducts and by almost 1/2 in the 40-cm field. TCVE vent duct diameter has no more influence on cooling efficiency in testing region.