Subproject C1

Usage Monitoring of load-carrying systems and damage detection

The aim of subproject C1 was to control uncertainty that may occur during the estimation of the actual loading state of a load-carrying structure.

Therefore, the methodology developed within the SFB 805 including the uncertainty model provides the basis for a structured and consistent description of uncertainty in load-monitoring. The functional fitness of the proposed load-monitoring with uncertainty was tested by estimating a single harmonic lateral load and a static axial load applied on a simple beam-column system in numerical and experimental simulations. The influence of uncertainty in the mathematical model and the measurement signals on the estimated load was shown in numerical as well as in experimental simulations and was presented in a structured and consistent way by the use of the process model developed in the SFB. With that, it was possible to vividly represent the propagation of stochastic deviations in the measurement signals and systematic deviations in the parameters of the mathematical model. However, a detailed analysis of the cause-and-effect-relationship e.g. the effect of nonlinearities, reduced models etc. on the estimated loads could not be performed. These relations are, among others, scopes of investigation in the new subproject C5.

With the ended subproject C1, first basics to analyze uncertainty in a load-monitoring were developed. It was possible to represent and evaluate uncertainty within several processes in load-monitoring by the uncertainty model and the process model proposed in the SFB. The scientific perception in load-monitoring with uncertainty in combination with the studies of structure-propertie-interaction between passive and active components in the subproject C3 build a basis for the new subproject C7. Results of the subprojects C1 and C3 help to realize new methods of structural health control in Subproject C7.

[1] Engelhardt, Roland A.; Koenen, Jan F.; Enss, Georg C.; Sichau, Adrian; Platz, Roland; Kloberdanz, Hermann et al. (2010): A Model to Categorise Uncertainty in Load-Carrying Systems. In: Peter Heisig, P. John Clarkson und Sandor Vajna (Hg.): Proceedings of the 1st International Conference on Modelling and Management of Engineering Processes (MMEP 2010). Cambridge/UK: Springer-Verlag London, S. 53–64.

[2] Koenen, Jan F.; Platz, Roland; Hanselka, Holger (2010): A Survey to Control Uncertainties by Comprehensive Monitoring of Load-carrying Structures. In: Proceedings of SPIE Vol. 7647 Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems. SPIE international society for optics and photonics. San Diego, CA/USA, 76471R.

[3] Koenen, Jan F.; Platz, Roland; Hanselka, Holger (2010): An Approach to Quantify the Influence of Uncertainties in Model-based Usage-Monitoring of Load-Carrying Systems. In: Proceedings of ISMA 2010 24th International Conference on Noise and Vibration Engineering. ISMA Advance Conference Programme. Leuven/Belgium, S. 857–866.

[4] Koenen, Jan F.; Enss, Georg C.; Ondoua, Serge; Platz, Roland; Hanselka, Holger (2011): Evaluation and Control of Uncertainty in Using an Active Column System. In: AMM 104, S. 187–195. DOI: 10.4028/

[5] Koenen, Jan F.; Platz, Roland; Hanselka, Holger (2011): General approach and possibility to evaluate uncertainty in estimating loads acting on a beam. In: Proceedings of International Conference on Structural Engineering Dynamics ICEDyn 2011. Instituto Superior Técnico, Technical University of Lisbon. Tavira/Portugal.

[6] Engelhardt, Roland A.; Koenen, Jan F.; Brenneis, Matthias; Kloberdanz, Hermann; Bohn, Andrea (2012): An approach to classify methods to control uncertainty in load-carrying structures. In: Applied Mechanics and Materials, Trans Tech Publications 104, S. 33–44. DOI: 10.4028/

Subproject Managers

Prof. Dr.-Ing. Holger Hanselka
Dr.-Ing. Roland Platz