Evaluation Settlement models Test Embankments Bloemendalerpolder – GeoImpuls Program

In the Bloemendalerpolder two test embankments were constructed, starting October 2010, to study the long term behavior of embankments on very soft soils with respect to settlement and lateral pile loading resulting from horizontal soil deformations. A detailed description of the test embankments, performed soil investigation, laboratory tests and instrumentation is given in an accompanying paper. This paper provides a brief description of both test embankments consisting of sand fill with a height of 3.0 m and a plan area 26 × 36 m2 with slopes 1:2. At the embankment overlying 5.7 m of clay/peat, wick drains are installed at a triangular spacing of 1.0 m. The second embankment overlying 4.0 m of clay/peat is not provided with any additional drainage accelerating measures. From the laboratory tests settlement parameters were derived for three settlement models; Koppejan-Terzaghi-Buisman, NEN-Bjerrum isotache model and the a,b,c-isotache model. Additionally parameters for Terzaghi and Darcy consolidation models were derived as well: consolidation coefficient, permeability and strain dependent permeability strain factor. Based on applied field loading increments predictions were made. Test results of both embankments will be shown including predictions. Because of the limited dimensions of the test embankments a correction of the monitoring results is applied to match one-dimensional conditions. Based on the measurements a fit of input parameters for all models have been generated matching the settlement of both embankments. Based on these results recommendations are given for application of the models for the site preparation in the Bloemendalerpolder. Researchers, however, are invited to analyse the data to develop more general settlement models for such very soft soils