Project Details
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Characterization and modelling of the nonlinear material behaviour of coated fabrics for architectural membrane structures II

Subject Area Structural Engineering, Building Informatics and Construction Operation
Applied Mechanics, Statics and Dynamics
Term from 2015 to 2026
Project identifier Deutsche Forschungsgemeinschaft (DFG) - Project number 278626677
 
Final Report Year 2025

Final Report Abstract

The central goal of this research project was to significantly increase the accuracy of the finite element (FE) simulation of textile membranes to improve the structural stability, safety and cost-effectiveness of membrane structures. Focus was on the practicability of the improved simulation methods in engineering practice, as well as the economic feasibility of the experimental analyses required for this. Another focus was on analyzing the wellestablished elastic behaviour and the load history dependencies of the stress-strain paths. It was found that significantly more load cycles are required to achieve a good approximation of the elastic state than is usually investigated in practice. Not entirely negligible load history dependencies and the associated influence on the structural behaviour were also demonstrated and analysed. To optimise the material modelling, a polyconvex hyperelastic material model and an adaptive, stress-ratio-dependent method were developed for the steady-state elastic behaviour, which have shown great improvements of the purely linear elastic material model widely used in practice. In addition, an anisotropic visco-elastoplastic material law was developed and implemented, which was shown to describe the stress-strain hysteresis. Parallel to the development of the material models, the focus was on methods for determining their parameters, including a new type of small-scale test rig, and the quantification of the properties. It has been shown that the consideration of the stress ratio dependence and the service stress level has a clear positive influence on the fit of the stiffness parameters in all material models. Stiffness was also found positively correlated with tensile strength. Stiffness parameters can be classified based on tensile strength regardless of the material model. An extrapolation method was developed to consider the elastic state without testing thousands of load cycles, which allows the estimation of stiffness parameters in a good approximation with only 20 load cycles. To validate the developed material modelling approaches and methods for parameter identification, a new type of large-scale membrane component test rig was developed and built. It enables the measurement of prestressed flat or spatially curved membrane structures under varying surface loads and thus provides reference data for comparative FE simulations.

Link to the final report

https://doi.org/10.17185/duepublico/83772

Publications

 
 

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