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New Third Rail Implementation System for Conventional Railroad Tracks in Service
Laura Montalbán Domingo,Clara Zamorano Martín,Julia I. Real Herráiz,Laura Gómez del Rey 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.2
Two track gauges coexist in Spain, the Iberian gauge (1668 mm) and the international gauge (1435 mm). Solutions applied on the track were considered to improve the interoperability in Spain. First solution proposed was tracks with two-gauge-ready sleepers. This solution allows changing the gauge from Iberian to International gauge or from International to Iberian gauge. The need of two gauges evolved this solution to the third rail system with two-simultaneous-gauge sleepers. In this paper, a new third-rail track solution is proposed. This solution is a novel system based on the introduction of special concrete blocks between the existing sleepers to fasten the third rail. Thus, the conventional railroad track becomes in a double-simultaneous-gauge lines without needing change existing sleepers and make long traffic interruptions of the track like in common third-rail systems. In the present study, threedimensional numerical models are generated using finite-element method. The analysis of the vertical displacements of the top head of the rails, vertical stresses transmitted to the substructure layers and vertical track stiffness, demonstrate the good vertical performance of the new system compared to the conventional lines with dual-gauge-ready sleepers and the common third rail tracks.
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Laura Montalbán Domingo,Beatriz Baydal Giner,Clara Zamorano Martín,Julia I. Real Herráiz 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.5
Rails are key elements in railway superstructure since these elements receive directly the train load transmitted by the wheels. Simultaneously, rails must provide effective stress transference to the rest of the track elements. This track element often deteriorates as a consequence of the vehicle passing or manufacturing imperfections that cause in rail several defects. Among these rail defects, transverse cracks highlights and are considered a severe pathology because they can suddenly trigger the rail failure. This study is focused on UIC-60 rails with transverse cracks. A 3-D FEM model is developed in ANSYS for the flawless rail in which conditions simulating the crack presence are implemented. To account for the inertialoss of the rail as a consequence of the cracking, a reduction of the bending stiffness of the rail is considered. The numerical models have been calibrated using the first four bending vibration modes in terms of frequencies. These vibration frequencies have been obtained using the Experimental Modal Analysis technique, studying the changes in the modal parameters of the rails induced by the crack and comparing the results obtained by the model with experimental results. Finally, the calibrated and validated models for the single rail have been implemented in a complete railway ballasted track FEM model in order to study thestatic influence of the cracks on the rail deflection caused by a load passing.
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Study of the influence of geometrical and mechanical parameters on ballasted railway tracks design
Julia I. Real,Laura Gómez,Laura Montalbán,Teresa Real 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.9
This paper investigates the vertical deflection on ballasted railway tracks from a set of cases of railway track typologies which differ in six track parameters: embankment height, ballast thickness, sleeper spacing, rail pad stiffness, Young’s modulus of the embankment material and the load applied to the structure. Finite element method has been the tool to assess the structural combinations and the results provided by linear and nonlinear analyses have been contrasted. Then, a new formulation for the deflection estimation in terms of the aforementioned parameters is presented based on a multiple regression model. The results provided by this formulation have been compared to those obtained from the classic Zimmermann theory. Finally, a stress analysis has been performed to complete the study and better understand the global behaviour of the railway structure. This article pretends to improve the design process and construction of ballasted railway tracks by means of proposing a formulation which estimates the track deflection to obtain the optimum track stiffness.
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Asian studies degrees and intercultural competence: The case of Spain
Ana Rosa del-Águila-Obra,F. Manuel Montalbán-Peregrín,Antonio Padilla-Meléndez 한국교육개발원 2017 KEDI Journal of Educational Policy Vol.14 No.1
This paper analyses how Spanish Higher Education Institutions (HEIs) are implementing “internationalization at home” strategies through the introduction of Asian studies degrees to help undergraduate students to be ready to work in a globalized world. The selection of Asia as specialization reflects its relevance for HEIs, as the most influential geopolitical area in the context of the current economic and cultural globalization. Specifically, this study identifies the undergraduate Asian degrees developed by Spanish HEIs, in what ways they are interculturally oriented, and how the intercultural orientation was incorporated into the degrees. It is possible to identify in the programs a process of the incremental acquisition of intercultural competence, following these phases: general knowledge moves to socio-linguistic and instrumental knowledge, which then becomes intercultural self-awareness. This paper concludes that to implement successfully their strategies at home and, simultaneously, to embrace the increasing societal demand for enhanced intercultural skilled professionals, a higher level of intercultural awareness is needed in Asian studies degrees at Spanish HEIs. The paper ends with some recommendations for educational policy-makers.
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