Actuation of structural concrete elements under bending stress with integrated fluidic actuators

摘要

The growing world population and the associated availability problem of mineral resources pose a major challenge to the construction industry. In some parts of the world there is already a scarcity of sand, the main ingredient of concrete. Conventional load-bearing structures are oversized for most of their lifetime, as the design loads rarely or never occur. The Collaborative Research Centre SFB1244 "Adaptive Skins and Structures for the Built Environment of Tomorrow" at the University of Stuttgart deals with this challenge by applying the concept of adaptivity to building structures and envelopes. Adaptivity means the ability to react to external effects by implementing sensors, actuators and control units into a building component. In this context the subproject C02 "Integrated fluid-actuators" investigates the resource saving potential of adaptive beams and slabs. In this article, concepts for the integration of actuators into concrete components under bending are presented. Previous actuation concepts do not allow to react to different external loads. Here, either the actuators are added from the outside or single members of truss structures are replaced by actuators. In the presented investigation actuators are integrated into the compression zone of a beam. These newly developed actuators expand due to a hydraulic overpressure and counteract the stress state from the external loads which allows to react to different loads specifically.