Soft clay properties in a layered clay-sand reclamation

Abstract

An economically viable method of land reclamation, the layered clay-sand scheme, has resulted from a series of research and development works at the National University of Singapore. The scheme replace scarce and costly sand with hydraulically dredged marine clay by sandwiching clay layers between thin sand seams to reduce the drainage path. The key to the success of the scheme is the ability to form a thin sand seam on top of the hydraulically dredged marine clay with minimal sand losses and within a short period of time from the completion of clay filling. This is demonstrated to be feasible in the laboratory through controlled sand penetration experiments as well as in a field trial. The method is now adopted for a 40 ha reclamation at Changi and preliminary results are discussed in this paper.