Enhanced Interoperability between Geotechnical and Structural Engineering for 3D Building Models

Conventional structural design in building construction is commonly based on the static analysis of the load flow using 2D submodels. Hence, the deformation compatibility and stress redistribution between the structural members of the building are not adequately regarded. In addition, the structural and the subsoil responses are usually assessed based on isolated analyses which use the subgrade reaction modulus as a coupling interface. Many researchers have shown that using the subgrade reaction method can lead to an uneconomic foundation design. Furthermore, the subsoil response generally affects the submodel of the foundation slab or basement, respectively. This leads to a strong simplification of the total stiffness of the building, and results either in conservative or unsafe results depending on the members under consideration. In contrast, the static analysis with a holistic 3D model allows for a more realistic load flow within the building. However, this requires not only an accurate representation of the stiffnesses of the structural members and their connections in the respective limit states, but also an accurate representation of the ground deformation in the calculation model. This contribution aims to enhance the interoperability between geotechnical and structural engineering for 3D building models. The contribution begins with a critical assessment of the subgrade reaction method. The core of this contribution proposes an alternative approach to account for soil-structure-interaction effects for 3D building models by exchanging nodal displacements, instead of using the subgrade reaction modulus.