Consolidation of Clay with a System of Vertical and Horizontal Drains

Consolidation of inhomogeneous clay with a system of horizontal and vertical drains is considered. Horizontal drains in the system are made of multiple thin pervious layers such as sand layers and geotextile sheets, while vertical drains are vertical cylindrical drains. Consolidation behavior with the drain system is formulated using the transfer matrix method. Special care is given to formulation of thin pervious layers for efficient computation. The developed formulation is verified using available numerical and field information. Parametric studies are conducted to study the consolidation characteristics of clay with the drain system. Based on the findings, a design method for an optimum system of horizontal and vertical drains is proposed and design charts are presented for such a design.