Smart Materials For The Realization Of An Adaptive Building Component

This research focusses on the realization of adaptive architecture with the use of advanced material technology. Current material research has shown significant advances with the development of “smart” materials. Smart materials are “capable of automatically and inherently sensing or detecting changes in their environment and responding to those changes with some kind of actuation or action”. These materials have intrinsic characteristics that enable the detection of an external stimulus and initiate an appropriate action, by adapting the material properties. Thus, smart materials have both sensory and actuation characteristics. By introducing smart materials in the building system immediate adaptive environments can be realized. The purpose of this research is to study the application and performance of smart materials for the realization of a shape morphing adaptive building component (ABC). The ABC should be able to realize a reversible hinge-like deformation. This means that a flat strip of materials should be able to bend into a 90° angle. The deformation should be fixated without constant energy input and recover into the initial flat configuration when desired. This research has started with an overview of the current state of adaptive architecture. Additionally, the application of smart material systems in architecture has been analysed. Design scenarios illustrate the application field of the ABC in the building system. When the building system can sense, process and act a new functional relationship is established between the building and its users. Immediate adaptive environments will change the user perspective on the built environment. Adaptive architecture will lead to a whole new paradigm of the building design and use. By the use of an internet inquiry and interviews, an insight is created into the participant’s receptiveness on immediate adaptive environments. Subsequently, the realization of a shape morphing building component with the use of smart materials is analysed. Shape adaptation in architecture is an interesting field of research in terms of functionality and realization. The performance is demonstrated by the fabrication of a full working prototype. After a smart material analysis, a composite system of shape memory alloys (SMAs) embedded in a shape memory polymer (SMP) matrix is presented that met the design requirements. The performance of this smart composite (SC) is analysed thoroughly. Both the SMA and the SMP are thermo-responsive materials and are activated by resistive heating. In general, it could be stated that the desired performance of the SC is realistic with the current materials. The performance of the SC prototype has shown a reversible shape deformation with the use of smart material systems. The significant technical advantage of this system is obtained by the fixation of the deformation without constant energy input. However, optimization in terms of cycling, performance and manufacturing is required in order to realize large–scale application in building systems. Accurate control of the individual smart materials systems is an important aspect in optimization of the SC performance. The thermoelectric activation of both the SMA and SMP were simulated by finite element modelling. The simulation software ANSYS is used here in order to create the model. This numerical model is validated by thermal experimentation with the use of a thermal imager. The validation experiments indicated that the finite element model is in good agreement with the physical material performance. Both the thermal activation of the SMAs as the integrated heating wires gave near identical thermal outputs. The finite element analysis is used for the determination of the most profound operating settings of both the SMAs as the heating wires. The numerical model can be adjusted to different dimensions and can determine the accurate thermal control of the smart composite. This research can be considered a first step into the new performance of architecture, whereby shape-morphing environments are realized by the use of smart material technology. The promising results of the fabrication and performance of the SC, show a realistic future for shape morphing building components based on intrinsic material characteristics. With the fabrication of the SC, the translation from virtual into real-time adaptive building components has been envisioned.Architectural Engineering + TechnologyArchitectur

Composietmateriaal omvattende een vormgeheugenpolymeer en een vormgeheugenlegering

Building TechnologyArchitectur

Mechanical characterization of a shape morphing smart composite with embedded shape memory alloys in a shape memory polymer matrix

This article presents a smart composite that shows a reversible bending deformation from an initial flat configuration into a 90° angle controlled by local thermal activation. The novelty lies within the structural fixation of the deformation at room temperature without continuous energy input. The new structural architecture of antagonistic performing shape memory alloy actuators embedded in a shape memory polymer matrix is presented. The shape memory polymer is locally heated from the rigid glassy state to the easily deformable rubbery state by integrated heating wires. By subsequent activation of the different shape memory alloy actuators by resistive heating, the reversible performance can be realized. By deactivation of the heating wires in the shape memory polymer, the shape memory polymer fixates the deformation in its rigid condition. The actuation characteristics of the smart composite are investigated by thermo-mechanical experiments. The performance of the smart composite was investigated by thermo-mechanical experimentation of the individual components. The results show that a 90° bending deformation is feasible with the current material dimensions, but repeated deformation is restricted due to fatigue of the alloy. By superposition of the bending forces of the individual components, it is possible to estimate the bending angle of the composite material

Intelligente daglichtsystemen: De toepassingsmogelijkheden van 'smart materials'

Building TechnologyArchitectur

Shape morphing wind-responsive facade systems realized with smart materials

This paper presents the opportunity to exploit the kinetic adaptation of the façade skin-roughness for enhancing the air-flow related characteristic of high-rise buildings. A conceptual design solution, in which the roughness adaptation is achieved by means of innovative shape changing materials, will be presented. Roughness elements located on the building envelope are able to modify the velocity field close to the façade; this modification has an effect on the natural ventilation and, primarily, on the heat exchange due to the wind convection. The study will deal with some simplified case studies of 3D geometries of round and square towers. Computation Fluid Dynamics (CFD) will be used to show how integrated roughness elements are able to affect the flow field along the building envelope. This paper contains some new ideas about wind optimisation of buildings and the opportunity to use shape changing materials for adaptive façade elements.Delft University of Technolog