多年冻土区路桥过渡段变形及地温场试验

根据多年冻土区路桥过渡段路基在竣工后3 a内的现场试验数据,分析了路基不同位置的地温变化、路基基底沉降变形和路基不同位置沿横向及纵向的沉降变形规律。结果表明:采用粗颗粒土填筑的过渡段路基对多年冻土区土体有明显的冷却效果,可防止多年冻土上限的下降;路基阳坡的沉降大于阴坡,而沿路基纵向,距离桥台越远路基沉降越大,但路基沿横向和纵向的沉降均满足工程要求;这种粗颗粒土填筑的路桥过渡段可适用于多年冻土区。

Experiment on Ground Temperature Field and Deformation of Bridge-subgrade Transition Section in Permafrost Regions

According to the field test data of the bridge-subgrade transition section in permafrost regions during 3 years after the construction,the ground temperature variation inside different locations of subgrade and the settlement deformation rules of subgrade basement and subgrade in different locations of the cross and the longitudinal section were analyzed.The results show that the cooling effect of soil under ground is obvious and the decline of permafrost upper limit may be restrained by the abutment filled with coarse grained soil.In the cross section of subgrade,the settlement of the southern slope is larger than that of the northern slope.The settlement of subgrade in the longitudinal section increases with the increasing distance away from the abutment.The settlements of the cross and longitudinal section are within the limitation of engineering,so this structure of bridge-subgrade transition section filled with coarse grained soil may be widely used in permafrost regions.