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A study of stone arch bridge’s flood reliability through a surrogate model appr...
Baron, Edward A.; Mendoza Cabanzo, Carlos; Bento, Ana Margarida; Matos, José C.; Calçada, Rui; Gavin, KennethEurope’s historic masonry arch bridges are culturally and economically significant, but their long-term safety must be ensured. Scour effects are the most common cause of collapse, so it is necessary to carry out structural assessments to mitigate the risk and prevent potential failures. In this study, a metamodel-based method was used to determine the probability of failure of an existing stone arch bridge in ...
Short and long term performance of a slab track in a transition zone: an embank...
Ramos, Ana; Correia, A. Gomes; Calçada, RuiRailway track transition zones are characterised by an abrupt change in track support stiffness, which increases dynamic wheel loads and leads to the acceleration of differential settlement and track degradation. This work aims to study concrete slab track transition zones, with a focus on embankment-to-tunnel sections. The analysis uses a hybrid methodology, combining 3D finite element modelling with empirical...
Prediction model for permanent deformation of railway subgrade using an artific...
Ramos, Ana; Correia, A. Gomes; Calçada, RuiThe prediction of the permanent deformation in the subgrade and its reliability is one of the main concerns of the Railway Infrastructure Managers, as it can influence the reduction of the maintenance costs of the track in service. This study proposes a novel methodology for predicting permanent deformation based on a parametric study performed using a hybrid approach that includes the short and long term perfo...
Performing fatigue state characterization in railway steel bridges using digita...
Nhamage, Idilson A.; Dang, Ngoc-Son; Horas, Claúdio S.; Poças Martins, João; Matos, José C.; Calçada, RuiRailway 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 efficienc...
Influence of train speed and its mitigation measures in the short- and long-ter...
Ramos, Ana; Calçada, Rui; Correia, A. GomesThe ballastless track is nowadays the most popular railway system due to the required low number of maintenance operations and costs, despite the high investment. The gradual change from ballasted to ballastless tracks has been occurring in Asia, but also in Europe, increasing the number of transition zones. The transition zones are a special area of the railway networks where there is an accelerated process of...
Online unsupervised detection of structural changes using train–induced dynamic...
Meixedo, Andreia; Santos, João; Ribeiro, Diogo; Calçada, Rui; Todd, Michael D.This paper exploits unsupervised data-driven structural health monitoring (SHM) in order to propose a continuous online procedure for damage detection based on train-induced dynamic bridge responses, taking advantage of the large-magnitude loading for enhancing sensitivity to small-scale structural changes. While such large responses induced by trains might create more damage-sensitive information in the measur...
Experimental Validation of a Double-Deck Track-Bridge System under Railway Traffic
Saramago, Gabriel; Montenegro, Pedro Aires; Ribeiro, Diogo; Silva, Artur; Santos, Sergio; Calçada, RuiThis article describes the experimental and numerical evaluation of the dynamic behaviour of the Cascalheira bridge, located on the Northern Line of the Portuguese railway network. The bridge has a short span formed by two filler-beam half-decks, each one accommodating a railway track. The study includes the development of a finite element numerical model in ANSYS® software, as well as in situ dynamic character...
Efficient multiscale methodology for local stress analysis of metallic railway ...
Horas, Cláudio; Jesus, Abílio M.P. de; Ribeiro, Diogo; Calçada, RuiThis paper presents an advanced submodelling methodology for local stress analysis of complex details of existing metallic railway bridges. The fatigue assessment of connections of large structures based on local methods leads inherently to a multiscale problem that can only be solved by adopting efficient numerical procedures. Aiming to overcome such limitations that influence the analysis process, submodellin...
A practical three-dimensional wheel-rail interaction element for dynamic respon...
Liu, Yongdou; Montenegro, Pedro Aires; Gu, Quan; Guo, Wei; Calçada, Rui; Pombo, JoãoA novel practical three-dimensional (3D) wheel-rail interaction (WRI) element is developed to simulate the interaction between a fast-moving wheel node and nodes of the rail. Different from most previous methods of wheel-rail contact in multibody dynamics, the wheel-rail relationship in this paper is simulated by the WRI element. The WRI element is implemented into a general finite element software framework (i...
Mechanistic-empirical permanent deformation models: laboratory testing, modelli...
Ramos, Ana; Correia, A. Gomes; Indraratna, Buddhima; Ngo, Trung; Calçada, Rui; Costa, Pedro AlvesGeomaterials exhibit elastoplastic behaviour during dynamic and repeated loading conditions. These loads are induced by the passage of a train or vehicle which then generates recoverable (resilient) deformation and/or permanent (plastic) deformation. Modelling this behaviour is still a challenge for geotechnical engineers as it implies the understanding of the complex deformation mechanism and application of ad...