Settlement Analysis of Widening Subgrade in the Highway Considering Technology Parameter of Composite Foundation

In the highway widening engineering, clay foundation is often treated by composite foundation. Considering pile length, pile distance and elastic modulus factors of composite foundation, settlement and level displacement deformation after old subgrade widening is analyzed by finite element. It is resulted that ground additional settlement, additional level displacement of foundation surface and level displacement of new subgrade slope toe are reduced with reducing pile distance. There is the critical pile length scope. Beyond this scope, enhancing pile length is not benefiting for reducing subgrade deformation. When elastic modulus of pile is enhanced, reducing trend of the corresponding settlement and level displacement gradually turn to be mild.