Efectos dinámicos laterales en vehículos y puentes ferroviarios sometidos a la acción de vientos transversales

En las ultimas decadas el aumento de la velocidad y la disminucion del peso de los vehiculos ferroviarios de alta velocidad ha provocado que aumente su riesgo de vuelco. Ademas, las exigencias de los trazados de las lineas exige en ocasiones la construccion de viaductos muy altos situados en zonas expuestas a fuertes vientos. Esta combinacion puede poner en peligro la seguridad de la circulacion. En esta tesis doctoral se estudian los efectos dinamicos que aparecen en los vehiculos ferroviarios cuando circulan sobre viaductos en presencia de vientos transversales. Para ello se han desarrollado e implementado una serie de modelos numericos que permiten estudiar estos efectos de una forma realista y general. Los modelos desarrollados permiten analizar la interaccion dinamica tridimensional tren-estructura, formulada mediante coordenadas absolutas en un sistema de referencia inercial, en un contexto de elementos _nitos no lineales. Mediante estos modelos se pueden estudiar de forma realista casos extremos como el vuelco o descarrilamiento de los vehiculos. Han sido implementados en Abaqus, utilizando sus capacidades para resolver sistemas multi-cuerpo para el vehiculo y elementos finitos para la estructura. La interaccion entre el vehiculo y la estructura se establece a traves del contacto entre rueda y carril. Para ello, se han desarrollado una restriccion, que permite establecer la relacion cinematica entre el eje ferroviario y la via, teniendo en cuenta los posibles defectos geometricos de la via; y un modelo de contacto rueda-carril para establecer la interaccion entre el vehiculo y la estructura. Las principales caracteristicas del modelo de contacto son: considera la geometria real de ambos cuerpos de forma tridimensional; permite resolver situaciones en las que el contacto entre rueda y carril se da en mas de una zona a la vez; y permite utilizar distintas formulaciones para el calculo de la tension tangencial entre ambos cuerpos. Ademas, se ha desarrollado una metodologia para determinar, a partir de formulaciones estocasticas, las historias temporales de cargas aerodinamicas debidas al viento turbulento en estructuras grandes y con pilas altas y flexibles. Esta metodologia tiene cuenta la variabilidad espacial de la velocidad de viento, considerando la correlacion entre los distintos puntos; considera las componentes de la velocidad del viento en tres dimensiones; y permite el calculo de la velocidad de viento incidente sobre los vehiculos que atraviesan la estructura. La metodologia desarrollada en este trabajo ha sido implementada, validada y se ha aplicado a un caso concreto en el que se ha estudiado la respuesta de un tren de alta velocidad, similar al Siemens Velaro, circulando sobre el viaducto del rio Ulla en presencia viento cruzado. En este estudio se ha analizado la seguridad y el confort de la circulacion y la respuesta dinamica de la estructura cuando el tren cruza el viaducto. During the last decades the increase of the speed and the reduction of the weight of high-speed railway vehicles has led to a rise of the overturn risk. In addition, the design requests of the railway lines require some times the construction of very tall viaducts in strong wind areas. This combination may endanger the traffic safety. In this doctoral thesis the dynamic effects that appear in the railway vehicles when crossing viaducts under strong winds are studied. For this purpose it has been developed and implemented numerical models for studying these effects in a realistic and general way. The developed models allow to analyze the train-structure three-dimensional dynamic interaction, that is formulated by using absolute coordinates in an inertial reference frame within a non-linear finite element framework. By means of these models it is possible to study in a realistic way extreme situations such vehicle overturn or derailment. They have been implemented for Abaqus, by using its capabilities for solving multi-body systems for the vehicle and finite elements for the structure. The interaction between the vehicle and the structure is established through the wheel-rail contact. For this purpose, a constraint has been developed. It allows to establish the kinematic relationship between the railway wheelset and the track, taking into account the track irregularities. In addition, a wheel-rail contact model for establishing the interaction of the vehicle and the structure has been developed. The main features of the contact model are: it considers the real geometry During the last decades the increase of the speed and the reduction of the weight of high-peed railway vehicles has led to a rise of the overturn risk. In addition, the design requests of the railway lines require some times the construction of very tall viaducts in strong wind areas. This combination may endanger the traffic safety. In this doctoral thesis the dynamic effects that appear in the railway vehicles when crossing viaducts under strong winds are studied. For this purpose it has been developed and implemented numerical models for studying these effects in a realistic and general way. The developed models allow to analyze the train-structure three-dimensional dynamic interaction, that is formulated by using absolute coordinates in an inertial reference frame within a non-linear finite element framework. By means of these models it is possible to study in a realistic way extreme situations such vehicle overturn or derailment. They have been implemented for Abaqus, by using its capabilities for solving multi-body systems for the vehicle and finite elements for the structure. The interaction between the vehicle and the structure is established through the wheel-rail contact. For this purpose, a constraint has been developed. It allows to establish the kinematic relationship between the railway wheelset and the track, taking into account the track irregularities. In addition, a wheel-rail contact model for establishing the interaction of the vehicle and the structure has been developed. The main features of the contact model are: it considers the real geometry