Investigation of laboratory tests on cooling effect of embankments with perforated ventilation pipes

A technique of laboratory tests for the cooling mechanism in embankments with perforated ventilation pipes was introduced.Various ventilated-embankment samples with dimensions of 100 cm×60 cm×100 cm under cyclically fluctuating upper-surface temperature were studied experimentally.It was shown that the ventilated embankment with perforated ventilation pipe could enhance the cooling effectiveness of the embankment base.The cooling of perforated ventilation pipe embankment was effective only under negative temperature.Temperature change amplitudes and distribution ranges of negative temperature in the vicinity of air inlet of ventilation pipe were larger than those in the vicinity of air outlet of ventilation pipe.This was a direct consequence of unsymmetrical temperature distribution along a wind direction parallel to the ventilation pipes.