Study On The Stability Of Embankment On Valley -type Soft Ground Of Highway

Along with the western development strategy's implementation in our country, the highway enters the mountainous area gradually, and the highway's construction enters the quick period of expansion in the mid-west area. The roadbed in mid-west area has its own characteristic, which is different from that in the coastal plain area. To correspond to the local economic development, the natural tourism landscape and the environmental conditions.The soft soil's intensity is low, and it's compressibility is high. In addition, the valley land between mountains has it's unique landform characteristic, so the thickness of the soft soil on the road is uneven, and the project problem is prominent. So reinforcement processing measures must be taken before the highway is engineered on this kind of soft-base, and the economic analysis is also necessary, finally, the plan will be confirmed.At first, this paper reviewed the action mechanism of the plastic drainage board, the geotechnical grille and the gravel pile, and the development actuality of the embankment on soft ground. According to the collected materials of soft base in Sichuan area, the characteristics of embankment on valley-type soft ground and the common disease and breakage form were summarized.On this basis, several reinforcement processing measures, which used plastic drainage boards, geotechnical grilles, gravel piles, and sand cushion, were compared by Bishop method, and these measures were compared again by Finite Element method. Also, these treatments's costs were compared. At last, the conclusion was that the most economic and effective processing measure was that combined plastic drainage boards with geotechnical grilles.Besides, combining the feature of the project area with relative research conclusion, some regularitys on designments about stability and constructions of Embankment on Valley -type Soft Ground of Highway of this area were summarized.