Design and simulation of an actively controlled building unit

[EN] Conflagrations often lead to catastrophic phenomena in several countries across the globe during the summer period. Such phenomena advocate for multidisciplinary research activities including on- and off-site investigations of data-collection and evaluation as well as event-based virtual scenarios and action solutions respectively. In this framework, a temporary building unit is proposed to host single researchers in remote environments. The unit consists of a lightweight structure that can be easily erected and actively controlled. The unit is supported on four diagonals anchored to the ground and it has a circular horizontal and an elliptical vertical section. The core consists of a glass-fiber polymer (GFRP) cone base at its lower level, vertically positioned GFRP bending-active strips and a GFRP cone at its upper level. The cones are vertically connected through tendons that are activated by linear motion actuators. The structure consists of a double layer gridshell of GFRP bending-active rods and a semitransparent ETFE membrane with embedded thin-film CIGS photovoltaics. Sensors on the membrane transfer continuously the external wind pressure to a control system for the adjustment of the spatial shape of the unit through the tendons. The paper displays the design of the unit in its components, and emphasizes on its adaptivity features with regard to the structural deformability in parametric associative design logic. The methodology followed serves as a basis for further iterative analyses with regard to the form optimization of the structural elements, the system’s load-deformation and dynamic behavior.Ioannidou, P.; Kontovourkis, O.; Phocas, MC. (2023). Design and simulation of an actively controlled building unit. Editorial Universitat Politècnica de València. 250-259. https://doi.org/10.4995/VIBRArch2022.2022.1513025025

New perspectives in architecture through transformable structures: A simulation study

Structures enabling transformability of buildings, components and materials at different levels gain significance in view of a sustainable built environment. Such structures are capable of obtaining different shapes in response to varying functional, environmental or loading conditions. Certain limitations of classic tensegrity and scissor-like structures, applied so far in an architectural and engineering context, are attributed to a limited number of possible configurations and a big number of actuators required. In this context, rigid-bar linkages offer a promising alternative with regard to constructability, modularity, transformability and control components integration. In achieving improved flexibility and controllability with a reduced number of actuation devices, a kinematics principle has been previously proposed by the authors that involves the reduction of the system to an externally controlled one degree-of-freedom mechanism in a multistep transformation process. The paper presents application of the kinematics principle in two classes of a transformable spatial rigid-bar linkage structure. Investigation of the system kinematics was conducted using parametric associative design. The kinematics principle is applied on a torus-shaped spatial structural system composed of planar interconnected linkages. Alternative motion sequences of multiple transformation steps by the planar linkages can be implemented for the stepwise adjustment of the joints to their desired values. The actuators employed are positioned at the ground supports and are detached from the main structural body. Thus, minimum structural self-weight, simplicity and reduced energy consumption become possible. The transformation approaches using parametric associative design are exemplified based on a selected motion sequence pattern. The case study demonstrates the high degree of control flexibility and transformability of the system

JOHN ARGYRIS AND HIS DECISIVE CONTRIBUTION IN THE DEVELOPMENT OF LIGHT-WEIGHT STRUCTURES. FORM FOLLOWS FORCE

Abstract. This presentation contains an introductory outline of the biography and major achievements of John H. Argyris in the area of computational mechanics, emphasizing their influences on the development of lightweight structures. His contribution to the development of the Finite Element Analysis and his subsequent influential work at the University of Stuttgart are also addressed herein. The main areas of interest are the numerical methods of analysis initiated by John Argyris on the design of long-span net structures, since their origin, in the early 70ies. The design methodology applied for the first time at the University of Stuttgart at that time, based on computer applications of analysis is briefly documented. Most important, reference throughout the presentation is made to the cable-net structure for the roof of Munich 1972 Olympics-Arenas. The particular project, the first of its kind worldwide, represents historically the first architectural-engineering, holistic design approach of long-span cable-net structures, attaining the borders of structural engineering of its time. The structural requirements demanded equilibrium between the architectural form concept and the structural analysis; the latter is based on the concept of form finding as an interactive result of defined loading case, and led to the first large-scale computer applications. Further developments from John Argyris and his research team are highlighted herein in the respective interdisciplinary research, which followed at the University of Stuttgart in the time range of the subsequent 15 years, ever since being invaluable in structural engineering and the development of high-technology architecture.