INFORMATION RICH DESIGN PRACTICES
A BRIDGE TOO FAR
Loading: karamba “mesh load“ 3kn/m2 applied within the dotted area + gravity load maximum deflection: 4 mm
Surface without rigidisation
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MODELLING EXPERIMENTS
property calculation
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A series of modelling experiments are made to establish the representation of geometry for structural analysis, to identify an analysis approach, and to identify appropriate output values. The first of these experiments shows that including rigidisation geometries within the simulation model effects the calculated structural behavior, but also reveals that modelling these geometries at different resolutions produces very different predictions. To determine the ‘right’ resolution to model these geometries – one that accurately simulates structural behavior using lower geometric resolution – deflections simulated using models with stepped decrease in resolution were compared to those of a baseline high resolution model, until an unacceptable deviation was reached. The integrated FE tool Karamba is used to predict behavior and deflections of the entire structure. This design-integrated simulation is validated against simulation using Sofistik as well as empirical load testing of prototypes. Tests of different load cases defined an approach that tested 6 load cases – the full weight of a person on each of the 6 central panels – to find the maximum deformation and measure the elastic deformation energy per panel.
Loading: karamba “mesh load“ 3kn/m2 applied within the dotted area + gravity load maximum deflection: 17mm
Surface without rigidisation
Deflections
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30 Aenean varius porta purus varius porta 31 Validating modelling
assumptions and evaluations to make sure that the model “reasonably accurately“ represents the structural system
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Load Area (red) and deformation in LC 2
Load Area (red) and deformation in LC 6
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CITA Complex Modelling
design geometry
Deflections
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