Construction of underwater dykes using geotextile containment systems

摘要

Rock is the conventional building block for construction of underwater dykes. Recently, geotextiles have been used to contain soils to form units that replace rock as the building blocks of hydraulic structures. Such systems, which include geobags, geomattresses, geotubes and geocontainers, can be economical alternatives to rock. The economics further improve when marine excavations within project sites are used as infill material. Design may be divided into two parts, i.e. internal stability and external stability. Internal stability design involves ensuring each unit remains intact over the design life e.g. the geotextile and seams are strong enough to prevent rupture and soil loss through geotextile is limited. The external stability design concerns the response of the units to external influences e.g. ability to withstand impacting hydrodynamic forces, geotechnical forces, etc. The application of geotextile containment systems to construct underwater dykes is discussed. Two recent projects in Asia are presented.