Abstract: A series of the repeated load tri-axial tests considering 24 working conditions were conducted to investigate the relationship between permanent deformation and loading times of loess subgrade. The correction and calibration of current Tseng-Lyttonm’s permanent deformation prediction model’s parameters was carried out by statistics regression. The subgrade permanent deformation under various load and traffic conditions was calculated by the itemized and layered summation method. And then the distribution curve of vertical permanent deformation accumulated at the subgrade top surface was obtained, which was in transverse direction among the road. The results indicate that compared with ordinary highway, the distribution curve of vertical permanent deformation accumulated at the subgrade top surface of coal highway caused by the lane-choice of light-vehicle and heavy-vehicle is similar to a “spoon” at the road cross-section; the curvature is larger and the differential deformation is more significant.

Key words: road engineering, loess subgrade, permanent deformation, spatial shape, distribution characteristics

摘要： 通过室内重复加载三轴试验，测试了24种工况条件下黄土路基永久变形与加载次数之间的关系；采用统计回归的方法对现有路基永久变形预估模型进行参数修正与标定；采用分层分条总和法计算了不同行车荷载及交通条件下的路基永久变形，得到了路基顶面累积竖向永久变形沿道路横向的分布曲线。结果表明：与普通道路相比，运煤公路轻、重车辆分车道行驶引起的路基顶面竖向累积永久变形曲线在道路横断面上的分布形态呈“勺子”形，曲线曲率更大，差异变形更加显著。

关键词: 道路工程, 黄土路基, 永久变形, 空间状态, 分布特性