The Application of D-M Method in Embankments on Deep Soft Clay

This paper presents a new method to improve embankment on deep soft clay in China. The method, briefly named D-M method, combines the prefabricated vertical drains (PVD) and the cement deep mixing method (DMM) together to consolidate deep soft soil foundation. The short deep mixing columns improve the shallow soft soil and long PVDs accelerate the dissipation of excess pore pressure in the deeper soft soil layers. To evaluate the efficiency of the D-M method, a numerical study was conducted using the design parameters obtained from the Huaian-Yancheng Highway project by the 2-dimensional finite element software Plaxis. Results showed that the new method succeeds in consolidating deep soft soils below the deep mixing columns and improving the stability of the highway embankment.