| Salty soil, as a special soil with unique microstructure and engineering properties, easily results in the damage of highway pavement, such as Road surface subsidence, pavement pumping, subgrade dissolve trapped, Frost heaving, etc. Salty soil is generally not used as subgrade filled in highway engineering, but even with the qualified soil subgrade, subgrade soil secondary salinization is also easily happened in salty soil distribution area because of the influence of salt in salty soil foundation and in groundwater. Therefore, the study of influence of salty soil foundation to highway subgrade is very important.The thesis is based on the oil nature of flood area, salty soil distribution, geological and hydrological conditions in Shandong province, simulating the influence of foundation what with underground mineralized water in salty soil area and saliferous foundation by the experiments of standpipe and subgrade model experiments. Research the movement and distribution of salt water in the subgrade soil and the salinity collective position and quality along with the slender water in the foundation. Through the research, we would get the moisture and salinity collective distribution chart caused by the influence of foundation by slender water effect.Though the experiments, this paper explores the influence of salt content on the properties of subgrade soils after salt accumulation, including the influence law of soil CBR, liquid and plastic limits, shear strength and compression properties.By the finite element simulation method, this paper analyzes the variety of the roadbed overall force, displacement and stability when the nature of subgrade soil salinity changed.Sum up these studies and the existing experience in engineering, this paper put forwards the measures of subgrade filling in salty soil area. |
