Abstract:The mileage of highway construction at this stage is increasing in China. Compared with the conventional plain areas, the highway construction in the alpine regions should overcome various adverse effects brought about by saline soil subgrades. The common saline soil in alpine regions is rich in salt, which is prone to salt migration and crystallization so as to bring about the changes in the stability of roadbed slopes. The partition layers are often set in the existing engineering construction schemes. But, the study on the influence of partition layer thickness on the stability of subgrade slope is still relatively weak. A variety of thicknesses of graded gravel partition layers are designed. The finite element simulation software is used to simulate and compare the results of the influence of each thickness of graded gravel partition layer on the stability of subgrade slope. The research results show that compared with the saline soil subgrade without the graded gravel partition layer, the stability of the subgrade slope with the partition layer is reduced, and is decreased with the increase of the partition layer thickness. After the thickness of the graded gravel partition layer is more than 30cm, the position of the dangerous sliding surface of the simulated subgrade slope touches the partition layer at the slope toe, and then its thickness continues to increase without the significant impact on the dangerous sliding surface.
