The Digital Building Kit – Isogeometric Mixed‐Dimensional Analysis of Modular Concrete Structures

Within the framework of the Priority Program SPP 2187 “ Adaptive modularized constructions made in a flux: precise and rapid building” , a method based on Isogeometric B‐Rep Analysis is further developed to enable the simulation, analysis, and optimization of modular structural systems. The proposed approach tightly integrates parametric CAD representations with structural analysis, forming a core component of a simulation‐based digital building kit. Modular construction models comprise shell structures described by trimmed NURBS multi‐patch CAD models, as well as solid structures based on three‐dimensional volumetric representations to capture geometrically complex concrete components. A central contribution lies in the development of robust coupling strategies for modular assemblies, including mixed‐dimensional solid–shell coupling, enabling flexible combinations of structural components within a unified analysis framework. The realization of the digital building kit is demonstrated through an open‐source software implementation in Kratos Multiphysics. Step‐by‐step coupling procedures are presented for a demonstrator consisting of modular, geometrically complex structures, illustrating the applicability of the proposed methods to simulation‐driven design workflows.