Study On The Method Of Backfill In Coastal Reclamation Project Of Tianjin Lingang Industrial Area

The areas of Tianjin Lingang Industrial Area (TLIA) are very large, and the soil dig from there is mostly silt, whose quality is very bad. So if we backfill the soil in traditional way, the lands form by backfilling are very soft, and the settlements are not uniformity. As a result of that, some soft-soil foundation reinforcements like plastic drainage combines with vacuum precompression must be adopted. It's no doubt that the costs and the time limit for the project will be largely increased. Aiming at this situation, this paper put forward a method of backfill in layers, which distinguishes the characters of soil, and then backfills according to the blueprints. Calculating the volume of soil is one of the important works in the coastal reclamation project, and the common methods of calculating the volume of soil are: transect, table, contours and digital elevation model. Practically the dissimilarity calculation method has different quantity and accuracy and different application range. This paper contraposes the conditions of the (TLIA), in the precondition of using table, introducing the concept of isoparametric finite element and isoparametric transform. And then improves the table, so we can calculate the volume and area of soil more precisely.This paper compares the traditional backfill-method and the method of backfill in layers in aspects of the settlement of base, the time of consolidation, the intensity of consolidation, the technical permission and the economy. When compareing this tow methods, I use the delaminate-summate method, the Terzaghi one dimension consolidation theory, the Mol-Coulomb theory and other guide lines.The conclusion of the compare is that the method of backfill in layers is better than the traditional backfill-method in the quality of the foundation and the economy. And also the method of backfill in layers is technical permission.