Hybrid Statics : advantages of hybrid versus separate structural calculation in lightweight structures engineering

Abstract

Lightweight structures as they are today not only need good inspiration, but also good engineering using sophisticated technologies. This thesis should give an insight into the differences that arise when calculating lightweight structures hybrid in holistic models on one hand or separate on the other. In the best case, this work allows the reader to develop a sense of what the differences are between the two opposing approaches when working on a particular project. It certainly cannot feel as good as collecting own experiences when making personal comparisons in special cases, but it should give an overview. Evaluations, graphs and visualisations provide insight into what it means to pursue the one way or the other, where the possibilities are, but also the risks that may arise. Basic principles are presented and the topic is examined in practice on the basis of a specific practical project. A feeling should be delivered to the reader for when the consequences of the design of a structure is not that immense when calculating conventional, and when hybrid calculation is essential.In the context of this thesis by hybrid is meant having a structure consisting of different types of structural behaviour. In this case, on one hand having lightweight components such as membranes, meshes, cushions, cable nets, etc., which can only take tensile forces, and on the other hand a supporting structure which can take further internal forces like compression and bending. Calculating separate means that lightweight components like membranes are calculated stand-alone in one model without the supporting structure. Afterwards the support forces from the lightweight calculation model are – better or worse – applied to the model of the pure supporting structure, dimensioning this then. In the hybrid approach the overall model is calculated and dimensioned in one holistic model.Since the possibilities of hybrid calculation given today with the software available on the market, hybrid calculation has already become relatively unproblematic. Nevertheless, very often and not to say mostly according to the authors' experience, the hybrid calculation is not used resulting in a series of bad consequences.The differences between the two approaches should be considered. What are the engineering implications? What are the cost impacts? What are the safety issues? What impact do the differences have on possible designs when following the one strategy or the other? As this thesis should be less theoretical than practice-oriented, it also examines the impact on companies operating in the market pursuing the different strategies. In particular, the negation of the hybrid approach can be decisive to win or lose projects in the global competitive market.