Soil Arching in a Piled Embankment under Dynamic Load

Abstract

Soil arching is a common phenomenon in pile-supported, geosynthetic-reinforced or unreinforced embankments resting on soft soil. Although the system behavior under static loading is well known (soil arching and bearing effects in geosynthetic reinforcement), the bearing behavior under dynamic loading is not yet fully understood and cannot be predicted. In this paper, the properties of soil arching under dynamic load have been investigated by performing numerical studies using the FEM and model tests. Embankments with different heights under dynamic load have been investigated. The behavior of soil arching under dynamic load can be classified into two types: for the model test without a geogrid and subsoil, the soil arching collapsed under dynamic load when the ratio of the height of the embankment to the diameter of the hole is less than 3, whereas the soil arching will not collapse under dynamic load when the ratio of the height of the embankment to the diameter of the hole is greater than 3. In numerical analysis, because of the existence of the geogrid, the value of the ratio of the height of the embankment to the center-to-center pile distance ensuring the stability of soil arching under dynamic load was 1.4, which is less than the value acquired in model tests, and it indicates that the existence of a geogrid and subsoil can improve the stability of soil arching under dynamic load.