多层高填路基变形规律研究

Deformation Rules of Multilayer High-Filled Subgrade

山区公路地形复杂,高填路基多且容易变形,多层高填路基中各路基之间的相互作用会进一步影响路基的变形。利用有限元数值计算方法,考虑不同的路基几何形状和填料的物理性质,探讨了多层高填路基的变形规律,算例表明坡间路基顶面两边缘沉降是不均匀的,其中坡率的影响较坡高和密度的影响更明显。为消除坡间路基内外侧的不利高差,上层路基应尽量远离下层路基,即上层路基的边坡尽可能缓些,最好不超过1∶2;而且应尽量降低路基高度或将密度较大的填料置于下层路基中,以利于其固结沉降,减小上层路基的变形。

The terrain of mountainous highway is complex, and there are many high-filled embankments which easily generate deformation. The interaction between different layers will further affect the deformation of the subgrade in muhilayer high-filled embankments. With the consideration of different geometric shape of subgrade and the physical nature of materials, the deformation rules of multilayer and high-filled embankment are discussed by finite element method （FEM）. Numerical examples show that the settlement of the top of two marginal subgrades is uneven. Compared with the impact of the slopeheight and density, the impact of the slope-gradient is more obvious. In order to reduce the negative medial-lateral elevation difference of the subgrade, the upper subgrade should be kept away from the lower classes,that is, the upper slope-gradient of the embankment should be as fiat as possible, preferably not more than 1 ： 2 ; and in order to facilitate the consolidation settlement and reduce the deformation of the upper embankment, it should minimize the height of embankment or place the filling materials with higher density in lower classes.