Layered Clay‐Sand Scheme of Land Reclamation

Dredged seabed sand and hill‐cut soil are economical fill materials for coastal land reclamation. Wherever these materials are scarce, the possibility of using other available materials such as marine clay should be studied. Hydraulically placed marine clay would pose problems related to sedimentation and long‐term settlement in the fill. By providing thin sand layers interbedded with marine clay, the settlement of the fill could be accelerated and the strength improved. A field test carried out on a recently reclaimed area shows the feasibility of reclaiming land using hydraulically placed clay and sand to form a layered clay‐sand fill. The main feature of this scheme is the ability to form thin horizontal sand layers on top of sedimented clay. The procedure is described in detail, and the performance of the fill is examined.