Study and Conduction on Liquefaction Mechansim of Sand Subgrade in the Yellow River Delta Area

From the mechanism of liquefaction of sand subgrade,combining with the geo-engineering characteristics of sand subgrade in the Yellow River delta region,and carrying out roadbed vibration test of sand liquefaction in the region,elements which can effect liquefaction of sand subgrade are gained in this paper. It is identified that the internal factors are the density of soil,soil moisture content and the presence of weak areas in soil; the main external factors are the size of load,the role of time and loading frequency. Pointing to internal and external factors of soil liquefaction,combining with stong shacking experience in constructing Qingdao-Yinchuan highway,a series of approaches are put forward to guide the road survey and design and subgrade soil liquefaction process in this region.