ABSTRACT
The design of the geosynthetic load transfer platforms above pile foundations is regulated according to the new published German technical guideline EBGEO 2010 (Recommendation for the design and the calculation of soil bodies reinforced with geosynthetics). The mentioned construction above piles is made of a combined body from soil and geosynthetics. The design of this construction is based on the main principle that the geosynthetic reinforced soil construction bridges the subgrade with poor bearing capacity among the vertical piles and transfers the vertical loads directly to the vertical piles. The design is significantly influenced by the subgrade bedding and the chosen load figure as design input parameters. In order to make a safe and accurate assumption for the bedding modulus of the subgrade, it is important to take the pronounced interactions among the elements of pile-soil-geosynthetics into consideration. According to EBGEO 2010, the bedding modulus as an input parameter is to be calculated with the help of an average subgrade stiffness modulus depending on the underlying soil layer thicknesses. The scope of the work is to analyze the mentioned pile-soil-geosynthetics interactions on the basis of numerical calculations (Vollmert & Doygun 2011) and to investigate the influence of the chosen two load figures based on in-situ investigation results from a realized structural project (Vollmert et al. 2006), with the help of which a better understanding of the subgrade bedding influence on the design is achieved.
