As the world population keeps growing, so does the demand for new construction. Considering material resources are limited, it will be unfeasible to meet such demand employing conventional construction methods. A new resource‐saving approach is provided by adaptive structures. Using sensors, actuators and control units, structures are enabled to adapt to loads, for example, to compensate for deformations. Since deformations are dominant in the design of bending‐stressed load‐bearing structures, adaptivity enables such structures to be realized using less material and achieving the same load‐bearing capacity in comparison to conventional designs. This article presents a concrete beam of typical building dimensions that compensates deflections by means of integrated fluidic actuators. These actuators offer the possibility of reacting optimally to general loading. The investigation is carried out on an approximately 4‐m‐long beam with integrated hydraulic actuators. To ensure the overall functionality, accurate dimensioning of the beam as well as the hydraulic system is mandatory. Analytical design of the beam and actuation system are carried out for predimensioning. Experimental testing validates the function and demonstrates that the adaptive beam works as predicted. A fully compensation in deflection is possible. Therefore, a significant increase in load‐bearing capacity is possible with the same material input compared to conventional beams.

Seit mehr als 20 Jahren setzt sich das Institut für Leichtbau Entwerfen und Konstruieren in interdisziplinären Forschungsvorhaben mit dem vermeintlichen Paradoxon „Leicht bauen mit Beton“ auseinander. In einem zweiteiligen Beitrag werden nun Auszüge aus der aktuellen Forschung hierzu vorgestellt. Während im ersten Teil dieses Aufsatzes der Fokus auf den Materialleichtbau gelegt wird, behandelt der zweite Teil den Strukturleichtbau mit dem Schwerpunkt auf Entwurfs‐ und Herstellungsansätzen für ressourceneffiziente, nachhaltige Betonstrukturen. Dazu zählen insbesondere neuere Untersuchungen zum Tragverhalten und zur Vorspannung von Bauteilen aus Gradientenbeton. Neben der Minimierung des Bauteilgewichts wird auch aufgezeigt, wie der ökologische Fußabdruck durch wiederverwendbare Betonsegmente weiter reduziert werden kann. Ansätze zur abfallfreien Herstellung von ressourcenschonenden filigranen Komponenten mittels additiver Fertigungsverfahren werden am Beispiel von 3D‐gedruckten Sandschalungen und Biobeton aufgezeigt. Über den klassischen Leichtbau hinaus werden abschließend Potenziale für weitere Materialeinsparungen durch adaptive Betonbauteile vorgestellt.

Previous work has shown that floor slabs make up most of the material mass of building structures and are typically made of reinforced concrete. Considering the associated resource consumption and greenhouse gas emissions, new approaches are needed in order to reduce the built environment’s impact on the ongoing climate crisis. Various studies have demonstrated that adaptive building structures offer a potential solution for reducing material resource consumption and associated emissions. Adaptive structures have the ability to improve load-bearing performance by specifically reacting to external loads. This work applies the concept of adaptive structures to reinforced concrete slabs through the integration of fluidic actuators into the cross-section. The optimal integration of actuators in reinforced concrete slabs is a challenging interdisciplinary design problem that involves many parameters. In this work, actuation influence matrices are extended to slabs and used as an analysis and evaluation tool for deriving actuation concepts for adaptive slabs with integrated fluidic actuators. To define requirements for the actuator concept, a new procedure for the selection of actuation modes, actuator placement and the computation of actuation forces is developed. This method can also be employed to compute the required number of active elements for a given load case. The new method is highlighted in a case study of a 2 m × 2 m floor.

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