Abstract The difference of solar radiation on different surfaces of embankment would cause uneven transverse deformation. The calculation method based on solar incident angles without considering the shielding to sunshine of high embankment in permafrost regions produces results that have large deviation from the actual situation especially for the permafrost near the toe of slope. A mathematical model of sunshine shield considering the time,the intensity of solar radiation,the position of sun and the track of embankment shadow was established. The mathematical model of embankment sunshine shield was verified with the results from the calculation method of K.Y. Kondratyev and the field test data. The concept of the rate of direct radiation and an empirical equation of surface temperature were proposed based on the shading theory. The results showed that there were differences in solar radiation on different surfaces of embankment. The direction and slope angle of embankment were found to be the major factors of influence. The solar radiation on permafrost surfaces around the embankment were found to be affected greatly,especially when the embankment is higher and the slope angle is larger. The closer to the toe of embankment slope,the weaker radiation it received. The solar radiation on permafrost in shaded slope side is weaker than sunny slope side. The difference of solar radiation on permafrost surfaces around the embankment should be considered in the stability estimation of embankment.
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Received: 04 March 2014
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