11 research outputs found
Aperfeiçoamento do algoritmo de otimização híbrido Pincus-Nelder e Mead para detecção de dano em estruturas a partir de dados vibracionais
Get PDFDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2014.Neste estudo, uma proposta de aperfeiçoamento do algoritmo deotimização híbrido estocástico-determinístico Pincus - Nelder e Mead(P-NMA) para detecção de dano em estruturas a partir de dadosvibracionais é apresentada. A formulação da função objetivo para oproblema de minimização é estabelecido pela diferença entre parâmetrosdinâmicos experimentais da estrutura na condição com dano e aquelescalculados utilizando um modelo de elementos finitos (MEF) querepresenta tal condição. Uma estratégia que permite acelerar aconvergência do algoritmo híbrido P-NMA Original para o problema deidentificação de dano é desenvolvida, sendo o algoritmo resultante aquidesignado por P-NMA Modificado. Para se poder ter uma base deescolha de parâmetros envolvidos na parte estocástica do algoritmo,funções testes de otimização global foram utilizadas. Em seguida, cincoexemplos numéricos de identificação de dano, todos retirados daliteratura, nomeadamente, uma viga simplesmente apoiada, uma viga embalanço, duas treliças planas e um pórtico plano com vários cenários dedano são apresentados. Os parâmetros dinâmicos utilizados nestetrabalho (frequências naturais e formas modais) são obtidos através dasolução do problema de autovalores. Para simular as características dainformação obtida por meio de um ensaio dinâmico real, foi consideradaa existência de apenas poucos modos de baixa frequência e também foianalisada a influência do ruído nas medições, que inclui igualmente aimprecisão na coleta de dados. Para testar a precisão e eficiência doalgoritmo resultante do aperfeiçoamento/modificações implementadas(o algoritmo P-NMA Modificado), uma comparação dos resultadosobtidos por meio deste novo algoritmo proposto e do algoritmo P-NMAOriginal é realizada. Além disso, os resultados do último exemplonumérico (pórtico plano) são comparados com aqueles existentes naliteratura, na qual o algoritmo P-NMA Original e o algoritmo genético(AG) foram utilizados. Em todos os casos analisados, as modificaçõesimplementadas funcionaram bem e os resultados foram promissores, oalgoritmo híbrido P-NMA Modificado foi mais preciso e apresentoumenor custo computacional comparativamente ao algoritmo híbrido PNMAOriginal e AG.Abstract : In this study, an improvement in the hybrid stochastic-deterministicoptimization algorithm Pincus-Nelder and Mead (P-NMA) for vibrationbaseddamage detection in structures is proposed. The formulation of theobjective function for the minimization problem is established by thedifference between experimental dynamic parameters of the damagedstructure and those calculated using a finite element model (FEM) thatrepresents such condition. A strategy which allows a quick convergenceof the Original hybrid algorithm P-NMA for the damage identificationproblem is developed, and the resulting algorithm is denominated hereas Modified P-NMA. In order to have a basis for the choice ofparameters involved in the stochastic part of the hybrid algorithm, testfunctions for global optimization were used. Thereafter, five numericalexamples, all taken from literature, namely, a simply supported beam, acantilever beam, two plane trusses and a portal plane frame with severaldamage scenarios are presented. The dynamic parameters used in thiswork (natural frequencies and mode shapes) are obtained by solving theeigenvalue problem. To simulate the characteristics of informationobtained in a real dynamic test, only a few modes of low frequency wereconsidered and the influence of noise in the measurements, whichinclude the errors during data collection was also analyzed. To test theaccuracy and efficiency of the resultant algorithm from theimprovement/ implemented modifications (the Modified hybrid PNMA),a comparison of the results obtained from this new proposedalgorithm and the Original P-NMA algorithm is performed. In addition,the results of the last numerical example (portal plane frame) arecompared with those available in the literature, where the Original PNMAalgorithm and the genetic algorithm (GA) were used. In allanalyzed cases, the implemented improvements were satisfactory andthe results were promising, the Modified hybrid P-NMA algorithm wasmore accurate and had lower computational cost compared to theOriginal hybrid P-NMA algorithm and GA
Performing Fatigue State Characterization in Railway Steel Bridges Using Digital Twin Models
Get PDFRailway infrastructures play a pivotal role in developing the national transportation system. Recently, the strategy of the railway engineer has been significantly shifted; along with the development of new assets, they tend to pay increasing attention to the operation and management of existing railway assets. In this regard, this paper proposes a Digital Twin (DT) model to improve fatigue assessment efficiency in the operational processes of railway steel bridges (RSBs). The DT concept mainly lies in the federation and interaction of a Fatigue Analysis System (FAS), which is based on Eurocodes principles, and a model in Building Information Modeling (BIM). Along with the proposed DT concept, a prototyping system for a real bridge is initiated and curated. The FAS is validated in good-agreement results with the ambient vibration test of the bridge (about 1.6% variation between numerical and experimental values), and close values were found between numerical and experimental stresses, the latter obtained by installing strain gauges on the bridge. The BIM model provides access to the numerical values of fatigue state results in a given bridge connection detail but also automatically represents that information in a 3D environment using a color-scale-based visualization process. Furthermore, a simulation model with the main input variables being the traffic and geometric conditions of the bridge is continuously updated for timely re-evaluation of the damage state, which shows promise for the lifecycle management of the bridge.This work was financially supported by: Base Funding—UIDB/04708/2020 of the CONSTRUCT—Institute of R&D In Structures and Construction—funded by national funds through the FCT/MCTES (PIDDAC) and by national funds through FCT—Fundação para a Ciência e a Tecnologia; SFRH/BD/151229/2021. This work was also carried out in the framework of Shift2Rail projects IN2TRACK3 [101012456- H2020-S2RJU-CFM-2020] for the development of a DT framework. This work is also co-funded by the European Social Fund (ESF) through the Northern Regional Operational Programme (Norte 2020) [Funding Reference: NORTE-06-3559-FSE-000176]; And was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020.The authors would like to acknowledge ANI (“Agência Nacional de Inovação”) for the financial support given to the R&D Project “GOA Bridge Management System—Bridge Intelligence”, with reference POCI-01-0247-FEDER-069642, co-financed by European Regional Development Fund (FEDER) through Operational Competitiveness and Internationalization Program (POCI)”
Strategies for Maximising the Value of Digital Twins for Bridge Management and Structural Monitoring: A Systematic Review
No full textBuilding Information Modelling (BIM) extends its utility to infrastructure management during the operational phase and can evolve into a Digital Twin (DT) when coupled with specific technologies or systems. In Engineering, Construction, and Operations (EC&O), BIM and DTs are strongly interconnected research topics. Especially for bridges, this relationship is represented by Bridge Information Modelling (BrIM) and Bridge Digital Twin (BDT). However, while this connection is recognised, it lacks developments regarding modelling strategies or data flow and integration. Therefore, the purpose of this study is to conduct a review of the current state of BrIM as an extension of BIM and its relationship with BDT, encompassing strategies for creating BrIM models of existing bridge assets. Additionally, it will explore integrating technologies or systems for structural performance monitoring and management (SPMM) to form BDTs. A systematic review was conducted using PRISMA protocol. Of the 3459 articles that were initially retrieved from a query of academic databases, 152 were assessed and classified manually, and 128 of these were selected for full content review. Analysis of the selected articles demonstrated the growing value of BDTs in SPMM of bridges, evolving from BrIM. Along with release of IFC4.3, BrIM development initiatives include IFC entity extension, IFC property sets usage, ontology development, and OpenBrIM implementation. Point cloud approaches are the most prevalent among different as-is BrIM modelling techniques, while parametric and data-driven approaches are gaining traction. Key challenges to BDT adoption, with respect to technological integration include interoperability, real-time performance, model updates, cost, and skill gaps
Strategies for maximising the value of digital twins for bridge management and structural monitoring: a systematic review
Get PDFBuilding Information Modelling (BIM) extends its utility to infrastructure management during the operational phase and can evolve into a Digital Twin (DT) when coupled with specifc technologies or systems. In Engineering, Construction, and Operations (EC&O), BIM and DTs are strongly interconnected research topics. Especially for bridges, this relationship is represented by Bridge Information Modelling (BrIM) and Bridge Digital Twin (BDT). However, while this connection is recognised, it lacks developments regarding modelling strategies or data fow and integration. Therefore, the purpose of this study is to conduct a review of the current state of BrIM as an extension of BIM and its relationship with BDT, encompassing strategies for creating BrIM models of existing bridge assets. Additionally, it will explore integrating technologies or systems for structural performance monitoring and management (SPMM) to form BDTs. A systematic review was conducted using PRISMA protocol. Of the 3459 articles that were initially retrieved from a query of academic databases, 152 were assessed and classifed manually, and 128 of these were selected for full content review. Analysis of the selected articles demonstrated the growing value of BDTs in SPMM of bridges, evolving from BrIM. Along with release of IFC4.3, BrIM development initiatives include IFC entity extension, IFC property sets usage, ontology development, and OpenBrIM implementation. Point cloud approaches are the most prevalent among diferent as-is BrIM modelling techniques, while parametric and data driven approaches are gaining traction. Key challenges to BDT adoption, with respect to technological integration include interoperability, real-time performance, model updates, cost, and skill gaps.CONSTRUCT -Institute of Research and Development in Structures and Construction(SFRH/BD/151229/2021
Integrating real traffic data for fatigue assessment of metallic railway bridges aided by digital twin technology
No full textDesenvolvimento do Modelo de Gêmeo Digital baseado no BIM para Avaliação de Fadiga em Pontes Metálicas Ferroviárias
No full textReal Traffic-Informed Fatigue Assessment of Metallic Railway Bridges with Support from Digital Twin Technology
Get PDFExpandindo usos BIM para caracterização do estado de fadiga em pontes metálicas ferroviárias
Get PDFNos últimos anos, a necessidade de envolver a tecnologia digital nos processos de
Gestão e Manutenção de Infraestruturas de Transporte (GMIT) tem sido crescente,
tendo em conta que hoje em dia, o desenvolvimento de qualquer sector está intrinsecamente ligado ao atual ambiente tecnológico digital. Como forma de responder a
esta necessidade, há uma tendência para expandir o âmbito de aplicação do Building
Information Modelling (BIM), tradicionalmente usado para projetos de edifícios, redirecionando os respetivos Usos BIM para áreas como Gestão e Manutenção de Pontes.
Uma das subcategorias que fazem parte do leque dos Usos BIM é a monitorização do
ativo na sua fase operacional. Este trabalho usa essa base para desenvolver um modelo experimental que combina um Sistema de Análise de Fadiga (SAF) e um modelo
BIM da ponte. Essas duas partes são ligadas a uma base de dados que possibilita a
atualização contínua do modelo global, formando um Gémeo Digital (GD), capaz de
caracterizar em qualquer instante a evolução de dano de fadiga em qualquer detalhe
de ligação da ponte. O SAF é baseado num modelo de elementos finitos que é associado ao Método de Danos Lineares Acumulados (MDLA) para a determinação do
dano por fadiga, ambos implementados em softwares comerciais, enquanto o modelo
BIM é desenvolvido a partir de softwares e programas de código aberto, que permitem maior flexibilização quanto à manipulação de objetos BIM, quase necessário para infraestruturas como pontes, incluindo a utilização do padrão IFC mais evoluído
(IFC4x3). A partir da base de dados, que contém parâmetros como condições de carga (tráfego ferroviário) e de geometria da ponte, o modelo global é continuamente
atualizado para reavaliação da evolução do dano por fadiga, e mostra-se promissor
para a gestão do ciclo de vida da ponte
AN HYBRID STOCHASTIC-DETERMINISTIC OPTIMIZATION ALGORITHM FOR STRUCTURAL DAMAGE IDENTIFICATION
Get PDFThis paper presents a hybrid stochastic/deterministic optimization algorithm to solve the target optimization problem of vibration-based damage detection. The use of a numerical solution of the representation formula to locate the region of the global solution, i.e., to provide a starting point for the local optimizer, which is chosen to be the Nelder-Mead algorithm (NMA), is proposed. A series of numerical examples with different damage scenarios and noise levels was performed under impact and ambient vibrations. To test the accuracy and efficiency of the optimization algorithm, its results were compared to previous procedures available in the literature, which employed different solutions such as the genetic algorithm (GA) and the harmony search algorithm (HS). The performance of the proposed optimization scheme was more accurate and required a lower computational cost than the GA and HS algorithms, emphasizing the capacity of the proposed methodology for its use in damage diagnosis and assessment
