以青海共和至玉树高等级公路中的实际设计断面为模型,通过数值模拟研究斜插式热棒路基和斜插式热棒-XPS复合路基的降温效果。结果表明,在气候变暖背景下,两种路基在一定时期内可以降低其下部多年冻土温度,提高路基下冻土上限,但随着气温逐渐升高,两种路基反压护道下多年冻土中有融化核出现,并且斜插式热棒路基下多年冻土中及斜插式热棒-XPS复合路基填土中有融化核出现;增加XPS保温板,在一定时期内可以提升斜插式热棒路基的降温能力,使斜插式热棒-XPS复合路基降温效果优于斜插式热棒路基,且前者冻土上限始终高于后者,但对于增强其长期降温的效果并不显著。
Abstract :Based on the model of the designed sections of Gonghe-Yushu high-grade road, the cooling effect of the inclined thermosyphon embankment and the inclined thermosyphon-XPS in- sulated board embankment were analyzed by numerical simulation. The results show that both of the two embankments could cool down the permafrost temperature and raise the permafrost ta- bles in the specified period under the background of global warming. However, with the air tem- perature rising, the melt bubbles would appear in the permafrost under the loading berms of the two embankments, the inclined thermosyphon embankment, and in the filling of the inclined thermosyphon-XPS insulated board embankment. Increase of the XPS insulated board could en- hance the cooling ability of the inclined thermosyphon embankment in a given period, and make the cooling effect of the inclined thermosyphon-XPS insulated board embankment better than that of the inclined thermosyphon embankment. The permafrost table of the former is higher than that of the latter, but the long-term cooling effect of the inclined thermosyphon embankment is not remarkable for the XPS insulated board.