中文摘要：

在多年冻土区桥头路基的病害程度远远高于普通路基,这主要是由桥头路基更为复杂的非均匀受热状况引起的.桥头路基各面太阳辐射的差异性是引起桥头路基受热非均匀的重要原因.针对传统分析方法无法对桥头坡面太阳辐射情况进行分析的问题,基于太阳辐射强度和太阳运动随时间的变化规律,提出利用遮阳原理对桥头路基各表面的太阳辐射规律进行研究的方法.分析发现冻土区桥头路基侧面和顶面之间的辐射情况存在很大的差异,其差异性与路基的走向、边坡角度等因素密切相关,其中边坡角度越大其差异性越大,东西走向路基的差异性最大.桥头坡面的太阳辐射存在明显的非均匀性,表现为越靠近桥面的辐射越少,其分布规律与路基走向、坡面高度、坡面角度等因素相关.

英文摘要：

The bridgehead was more likely to disaster than common embankment in permafrost regions.It is mainly caused by more complicated non-uniform heating condition.The difference in solar radiation for all bridgehead surfaces was the main reason of the non-uniform heat of bridgehead surfaces.The bridgehead slope cannot be analyzed by the traditional analysis method.Based on the change law of solar radiation intensity and shadow of bridgehead variation with time,the mathematical model expressing the relationship between time,solar radiation intensity,solar position and shadow track of bridgehead was established.The result show that there were quite differences in solar radiation energy between side slope surfaces and top surface of embankment segment,and the direction and side slope angel of bridgehead are the major influence factors.The differences enhance with the increase of the side slope angle.There was obvious asymmetry distribution of solar radiation on the surface of bridgehead,especially for the east-west.There was non-uniform distribution of solar radiation on the bridgehead slope.The closer the bridgehead slope gets close to the bridge floor,the fewer radiations it received.The direction,slope angle and height of bridgehead slope are the major influence factors of solar radiation on the bridgehead slope.