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Foundations for high‐rise buildings in Berlin – experiences in glacially overconsolidated soils Due to the challenge of continuing urban growth building projects require the planning and construction of heavily loaded foundations. With the building grounds of the North German Plane we come upon a Geotechnical structure of manifold glacial icing layers which composed a landscape of valleys, lakes, rivers and hillocks. With respect to ambitious building projects it is vital not only to categorize and subdivide the soil with regard to mechanical characteristics such as density and texture. In order to get a deeper understanding of the soil conditions and for an economic geotechnical design approach the evolutionary aspects and the time impact on structure and composition of the soil, especially with regard to its rigidity and load capacity need to be observed. Many projects in Berlin have shown that it is vital for the planning to deeply analyze the load history that influenced the soil from the beginning of its formation. The main factors that might have contributed to the soil capacity are e. g. glacial formations of the Pleistocene on the one hand and on the other hand man‐made effects due to former foundations or groundwater drawdowns. In addition to an outline on mechanical relations, practical examples are being given for heavily loaded foundations of high‐rise buildings. Furthermore, it is shown that a deep foundation is not always necessary but that a slab foundation might be a better and economically more feasible solution. [ABSTRACT FROM AUTHOR]

Challenges in foundations for high‐rise buildings in glacially preloaded soils The economical and safe design of foundations for high‐rise buildings in Berlin requires a realistic assessment of the expected settlements for both the building itself as well as for existing neighboring structures. In this context taking account of glacial preloading and the corresponding increase of soil stiffness has a significant impact on the quality of the settlement prediction. In this paper different approaches to derive soil stiffness parameters are compared with regard to settlement measurements at various buildings in Berlin. It can be shown that stiffness values based on the correlations of EC 7‐2 significantly underestimate the in‐situ stiffness of the soil types encountered in Berlin. A more realistic reproduction of soil stiffness is possible with the stiffness values of TEV Gesteinseigenschaften and a stiffness approach developed by the authors. In these approaches soil density respectively soil consistency as well as the geological history of the soil layers with regard to glacial preloading are taken into account. [ABSTRACT FROM AUTHOR]