Although they are very efficient structures, concrete shells have lost popularity due to the complexity of the
traditional construction process using cast-in-place concrete. A key concept to overcome the labor-intensive
formwork in situ is the segmentation of the shells into prefabricated parts. In order to avoid individual formworks
during prefabrication as well, the authors rely on extrusion-based 3D printing of strain-hardening cement based
composite (SHCC). The goal is a highly automated, scalable, and adaptable flow-prefabrication of modules
controlled by a holistic digital design process. Such the creation of modular free-form shell structures can be
accelerated significantly, resulting in structures comparable with gridshells. Starting with the problem statement
and the elaboration of the technology used, the main contribution of this research is the development of
geometrical methods for modularization based on given production conditions. The challenge lies in the freeform
geometry discretization with respect to the structural analysis and within the defined constraints such as
planar quads, no edge torsion, and minimal material consumption. Methods of discrete differential geometry for
circular PQ (planar quad) mesh generation are combined with Response Surface Methodology (RSM) for multiobjective
optimization of the global parameterized shape. The results were illustrated in a study case where the
geometrical and structural production parameters of starting and final shell are compared.