Martin Classen
RWTH Aachen University, Germany
Title：
From Fabrication Process to Structural Performance: Exploring Design Models for Digitally Fabricated Concrete
Abstract：
Digital fabrication offers a unique opportunity to rethink how reinforced concrete structures are designed and built. Material-efficient geometries, tailored reinforcement layouts and modular construction concepts become feasible only when structural design and fabrication technology are developed hand in hand.
This keynote introduces an engineering approach in which mechanics-based models of cracking, shear transfer and reinforcement interaction form the basis for structural design of components produced through multimodal digital fabrication. Such fabrication chains combine 3D printing, casting, extrusion, robotic placement of CFRP and steel reinforcement, and adaptive forming. Together, these processes enable slender, material-minimized elements and open pathways to modular systems that support circular-economy principles.
Key to this development is a deeper understanding of the structural behaviour of digitally fabricated components. New constitutive descriptions are required to capture stress-transfer mechanisms in thin-walled or topology-optimized geometries and in reinforcement configurations that differ fundamentally from conventional practice.
To establish these models, advanced characterization techniques—including multiaxial and interface-sensitive testing—and large-scale structural experiments are used to quantify the governing material and interaction laws.
The lecture presents how integrating mechanics-based design, digital fabrication strategies and advanced testing enables the development of reliable, code-compliant and structurally efficient reinforced concrete elements for the next generation of automated construction.
Bio:
Martin Classen is Chair and Professor of Structural Concrete at RWTH Aachen University and serves as Aachen site-speaker of the Excellence Cluster CARE – Climate-Neutral and Resource-Efficient Construction. His research focuses on the structural design of reinforced concrete using mechanics-based engineering models and on digital, material-efficient construction methods. A central theme of his work is understanding how mechanical principles—particularly crack formation, shear transfer and reinforcement interaction—can guide the design of concrete structures produced through automated and multimodal fabrication processes that combine 3D printing, casting, extrusion and robotic reinforcement placement.
He and his team develop advanced characterization techniques and conduct large-scale experiments to investigate the structural behaviour of digitally fabricated components with complex geometries and reinforcement layouts. Additional research interests include monitoring of existing structures using novel sensor systems. Classen is actively engaged in national research initiatives on climate-neutral and automated construction and collaborates closely with industry and public agencies.