@inproceedings{LiuLeimbachHartmann, author = {Liu, Xiangqin and Leimbach, Robert and Hartmann, Dietrich}, title = {SYSTEM IDENTIFICATION OF A WIND TURBINE STRUCTURE USING ROBUST MODEL UPDATING STRATEGY}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2774}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27744}, pages = {11}, abstract = {This paper presents a robust model updating strategy for system identification of wind turbines. To control the updating parameters and to avoid ill-conditioning, the global sensitivity analysis using the elementary effects method is conducted. The formulation of the objective function is based on M¨uller-Slany's strategy for multi-criteria functions. As a simulationbased optimization, a simulation adapter is developed to interface the simulation software ANSYS and the locally developed optimization software MOPACK. Model updating is firstly tested on the beam model of the rotor blade. The defect between the numerical model and the reference has been markedly reduced by the process of model updating. The effect of model updating becomes more pronounced in the comparison of the measured and the numerical properties of the wind turbine model. The deviations of the frequencies of the updated model are rather small. The complete comparison including the free vibration modes by the modal assurance criteria shows the excellent coincidence of the modal parameters of the updated model with the ones from the measurements. By successful implementation of the model validation via model updating, the applicability and effectiveness of the solution concept has been demonstrated.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{MiroHartmannSchanzetal., author = {Miro, Shorash and Hartmann, Dietrich and Schanz, Tom and Zarev, Veselin}, title = {SYSTEM IDENTIFICATION METHODS FOR GROUND MODELS IN MECHANIZED TUNNELING}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2777}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27771}, pages = {13}, abstract = {Due to the complex interactions between the ground, the driving machine, the lining tube and the built environment, the accurate assignment of in-situ system parameters for numerical simulation in mechanized tunneling is always subject to tremendous difficulties. However, the more accurate these parameters are, the more applicable the responses gained from computations will be. In particular, if the entire length of the tunnel lining is examined, then, the appropriate selection of various kinds of ground parameters is accountable for the success of a tunnel project and, more importantly, will prevent potential casualties. In this context, methods of system identification for the adaptation of numerical simulation of ground models are presented. Hereby, both deterministic and probabilistic approaches are considered for typical scenarios representing notable variations or changes in the ground model.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{MittrupSmarslyHartmann2003, author = {Mittrup, Ingo and Smarsly, Kay and Hartmann, Dietrich}, title = {Implementierung eines webbasierten Talsperren-Monitoring-Systems}, doi = {10.25643/bauhaus-universitaet.334}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-3347}, year = {2003}, abstract = {Die Bauwerks{\"u}berwachung gewinnt aus sicherheitstechnischen sowie aus wirtschaftlichen Gr{\"u}nden zunehmend an Bedeutung. Nicht nur die Bauwerkssicherheit kann durch leistungsf{\"a}hige Monitoring-Systeme angemessen beurteilt, auch die Nutzungsdauer bestehender Bauwerke kann durch die gewonnenen Informationen deutlich verl{\"a}ngert werden. Das vorliegende Papier beschreibt die Entwicklung eines webbasierten Talsperren-Monitoring-Systems, das die automatisierte Erfassung von Daten vor Ort sowie die computergest{\"u}tzte Aufbereitung und Analyse der gesammelten Messdaten erm{\"o}glicht. Das Monitoring-System ist durch seinen modularen Aufbau nicht auf die Talsperren-{\"U}berwachung beschr{\"a}nkt, sondern kann ohne großen Aufwand an andere {\"U}berwachungsaufgaben angepasst werden. Das System besteht aus drei wesentlichen Modulen: (i) einer erweiterbaren Klassenbibliothek, die die Steuerung der im Bauwerk installierten Messelektronik erm{\"o}glicht, (ii) einem webbasierten Datenerfassungsmodul, das neben der automatischen Datenerfassung eine Fernsteuerung der Messelektronik erlaubt und Funktionen zur Verwaltung der {\"U}berwachungsaufgaben bereitstellt, sowie (iii) einem webbasierten Visualisierungs- und Auswertungsmodul zur Aufbereitung und Analyse der gesammelten Daten. Alle an der {\"U}berwachung beteiligten Mitarbeiter k{\"o}nnen mit einem {\"u}blichen Web-Browser {\"u}ber das Internet auf das entwickelte System zugreifen; ein Zugriff mittels Mobiltelefon ist alternativ m{\"o}glich. Das implementierte Talsperren-Monitoring-System begleitet die beteiligten Fachleute von der Erfassung der Daten vor Ort bis hin zur Aufbereitung und Analyse der Messdaten an zentraler Stelle: Die Mitarbeiter werden durch einen einfachen Zugriff auf die installierte Messelektronik, automatisierte Messungen und umfangreiche Analysefunktionalit{\"a}ten bei ihren spezifischen Aufgaben unterst{\"u}tzt. Der bisherige manuelle Arbeitsaufwand f{\"u}r Datenerfassung, -transfer und Analyse wird somit deutlich reduziert.}, subject = {Talsperre}, language = {de} } @inproceedings{SikiwatBreidtHartmann, author = {Sikiwat, Tanongsak and Breidt, Michael and Hartmann, Dietrich}, title = {COMPUTATIONAL STEERING FOR COLLAPSE SIMULATION OF LARGE SCALE COMPLEX STRUCTURES}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2890}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28908}, pages = {9}, abstract = {In order to model and simulate collapses of large scale complex structures, a user-friendly and high performance software system is essential. Because a large number of simulation experiments have to be performed, therefore, next to an appropriate simulation model and high performance computing, efficient interactive control and visualization capabilities of model parameters and simulation results are crucial. To this respect, this contribution is concerned with advancements of the software system CADCE (Computer Aided Demolition using Controlled Explosives) that is extended under particular consideration of computational steering concepts. Thereby, focus is placed on problems and solutions for the collapse simulation of real world large scale complex structures. The simulation model applied is based on a multilevel approach embedding finite element models on a local as well as a near field length scale, and multibody models on a global scale. Within the global level simulation, relevant effects of the local and the near field scale, such as fracture and failure processes of the reinforced concrete parts, are approximated by means of tailor-made multibody subsystems. These subsystems employ force elements representing nonlinear material characteristics in terms of force/displacement relationships that, in advance, are determined by finite element analysis. In particular, enhancements concerning the efficiency of the multibody model and improvements of the user interaction are presented that are crucial for the capability of the computational steering. Some scenarios of collapse simulations of real world large scale structures demonstrate the implementation of the above mentioned approaches within the computational steering.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{SmarslyHartmann, author = {Smarsly, Kay and Hartmann, Dietrich}, title = {REAL-TIME MONITORING OF WIND CONVERTERS BASED ON SOFTWARE AGENTS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2891}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28916}, pages = {11}, abstract = {Due to increasing numbers of wind energy converters, the accurate assessment of the lifespan of their structural parts and the entire converter system is becoming more and more paramount. Lifespan-oriented design, inspections and remedial maintenance are challenging because of their complex dynamic behavior. Wind energy converters are subjected to stochastic turbulent wind loading causing corresponding stochastic structural response and vibrations associated with an extreme number of stress cycles (up to 109 according to the rotation of the blades). Currently, wind energy converters are constructed for a service life of about 20 years. However, this estimation is more or less made by rule of thumb and not backed by profound scientific analyses or accurate simulations. By contrast, modern structural health monitoring systems allow an improved identification of deteriorations and, thereupon, to drastically advance the lifespan assessment of wind energy converters. In particular, monitoring systems based on artificial intelligence techniques represent a promising approach towards cost-efficient and reliable real-time monitoring. Therefore, an innovative real-time structural health monitoring concept based on software agents is introduced in this contribution. For a short time, this concept is also turned into a real-world monitoring system developed in a DFG joint research project in the authors' institute at the Ruhr-University Bochum. In this paper, primarily the agent-based development, implementation and application of the monitoring system is addressed, focusing on the real-time monitoring tasks in the deserved detail.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{WellmannJelicBaitschHartmann2004, author = {Wellmann Jelic, Andres and Baitsch, Matthias and Hartmann, Dietrich}, title = {Distributed computing of failure probabilities for structures in civil engineering}, doi = {10.25643/bauhaus-universitaet.103}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1030}, year = {2004}, abstract = {In this contribution the software design and implementation of an analysis server for the computation of failure probabilities in structural engineering is presented. The structures considered are described in terms of an equivalent Finite Element model, the stochastic properties, like e.g. the scatter of the material behavior or the incoming load, are represented using suitable random variables. Within the software framework, a Client-Server-Architecture has been implemented, employing the middleware CORBA for the communication between the distributed modules. The analysis server offers the possibility to compute failure probabilities for stochastically defined structures. Therefore, several different approximation (FORM, SORM) and simulation methods (Monte Carlo Simulation and Importance Sampling) have been implemented. This paper closes in showing several examples computed on the analysis server.}, subject = {Konzipieren }, language = {en} } @inproceedings{WellmannJelicHartmann2003, author = {Wellmann Jelic, Andres and Hartmann, Dietrich}, title = {Einfluss von Kranfahrtlasten auf die lebensdauerorienteierte Auslegung von Rahmentragwerken}, doi = {10.25643/bauhaus-universitaet.375}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-3753}, year = {2003}, abstract = {Ziel des Teilprojekts C5 des Sonderforschungsbereichs 398 an der Ruhr-Universit{\"a}t Bochum ist die Entwicklung eines lebensdauerorientierten Entwurfsmodells f{\"u}r Stahltragwerke. Das Referenzsystem der letzten F{\"o}rderperiode war eine einschiffige Stahlhalle mit Kranbahnen. Der vorliegende Beitrag stellt die Ergebnisse einer Sensitivit{\"a}tsanalyse des Stahlrahmens unter Kranfahrtlasten vor. Diese Verkehrslasten wurden, v{\"o}llig entkoppelt von weiteren {\"a}ußeren Einfl{\"u}ssen wie Wind und Schnee, als poissongetriebene Pulsprozesse beschrieben, die zuf{\"a}lligen Eigenschaften der Kranfahrtlasten wurden in den Zufallsvariablen Pulsdauer und Pulsintensit{\"a}t ber{\"u}cksichtigt. Zur Minimierung des Rechenaufwandes der Lebensdauer-untersuchung wurden a priori einige Systemparameter anhand von Parameterstudien im Hinblick auf ihre dynamische Wirkung maßgebend festgelegt. In einer darauf aufbauenden Betriebsfestigkeitsuntersuchung wurden die Sch{\"a}digungseintr{\"a}ge in einer Rahmenecke infolge von jeweils einzelnen Pulslastereignissen berechnet und in einer Datenbasis abgelegt. Eine abschließende Distance-Controlled Monte Carlo Simulation der Pulsprozesse {\"u}ber einen maximalen Zeitraum von 100 Jahren {\"u}berf{\"u}hrte die Realisationen der einzelnen Pulslasten anhand der Datenbasis in Teilsch{\"a}digungen, welche nach der Palmgren/Miner-Hypothese zu einer Gesamtsch{\"a}digung aufsummiert wurden. Der Einfluss der Kranlasten auf den Entwurf von Stahlhallen wurde durch den Vergleich der berechneten Lebensdauer und der planm{\"a}ßig vorgegebenen Nutzungsdauer quantifiziert.}, subject = {Rahmentragwerk}, language = {de} }