GEOSYNTHETICS HYDRAULIC BARRIERS FOR COASTAL LANDFILLS

Abstract

This paper firstly describes the current legal requirements on hydraulic barriers for landfills in Japan, and the Geosynthetics barriers and its configuration that have been used in the coastal landfill sites. Then, two case histories are presented. One is a construction project of coastal landfill on permeable ground in the Inland Sea as the first case under the current legal requirements. In the project the double geomembrane Geosynthetics barrier system was installed on both side and bottom of the landfill. The highlights of analysis, design and construction methods conducted in the project are presented. The other is the development of new type clay barrier for coastal landfill that improves toughness of the brittle cement treated clay by inclusion of fibrous materials while keeping sufficient impermeability. The mechanical and hydraulic properties were examined in laboratory tests. Concept of mixing design was further clarified by plant mixing tests, and the performance of HCB in a practical use was verified through an actual experience in the field.