毛细阻滞型路基湿化病害中吸力分布规律

路基中的水分运移是引起公路湿化病害（工后沉降、差异沉降以及承载特性变化）的主要原因。然而，现有路基处理加固方式均属于内在处理，不能从本质上解决水分运移引起的病害，不仅增加成本，并且其长期性能尚不清楚。针对现有非饱和路基的内部水分运移规律进行研究，根据非饱和路基水分运移规律，一种新型路基形式被提出。在路基填土边坡上添加毛细阻滞层，进而有效减小路基中的水分运移。基于CODE_BRIGHT软件，通过比较有无毛细阻滞层的孔隙水压力和体积含水率分布，验证了毛细阻滞层在非饱和路基中的可行性。结果表明，毛细阻滞层下的路基，基质吸力变化明显减少。其影响范围缩小了80％，影响深度仅涉及到路基顶部．基质吸力的变化仅占普通路基的13％。根据吸力变化趋势可以预见，毛细阻滞层可以有效地降低路基的工后沉降和不均匀沉降。

Suction Distribution of a Wetting Subgrade with Capillary Barrier

Wetting distresses of subgrade （large post-construction settlement, different settlement and reduce of bearing） are usually caused by water migration. However, existing treatments of subgrade are inner treatment, no useful for preventing subgrade wetting. Not only construction cost increaseS, but their long term is not clear. Based on the mechanism of soil deformation and strength in unsaturated con- dition, moisture migration can be a reference to the design and construction of highway subgrade. Based on moisture migration for unsaturated soils, capillary barrier over subgrade has been proposed in this study. A numerical simulation using CODE_BRIGHT is conducted to compare pore water pressure and volumetric water content of the subgrade with and without capillary barrier. The numerical results show that the subgrade under capillary barrier can reduce the change of suction in the subgrade. Influence re- gion was reduced by 80% and influence depth just reached at the top of the subgrade. Comparing to tra- dition subgrade, the suction in the subgrade under capillary barrier decreased by 13%. Based on the trend of suction, using the subgrade under capillary barrier can effectively reduce post construction settle- ment and settlement diff