Page 303 - 360.revista de Alta Velocidad - Nº 5
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                                                                                      número 5 - junio - 2018. Pág 301 - 311













                   Importance of vertical rail track stiffness on dynamic overloading:

                                                          Limitations of the Eisenmann formulation



                                                                                Balmaseda, Lucía

                                                                           Gallego, Inmaculada

                                                           Sánchez-Cambronero, Santos

                                                                                            Rivas, Ana


                                                                                    University of Castilla-La Mancha
                                                                                                             1
                              Abstract
                              Since the development of high-speed rail in Europe in the 1970s, the vertical loads that are transmi-
                              tted to the rail track by vehicles have been measured. The formulations obtained by Eisenmann and
                              Prud’Homme are the most notable formulations of this period due to their extensive application.
                              The formula proposed by Eisenmann considered the quality of the rail track and was widely proven
                              for maximum speeds of 200 km/h. With the emergence of high speed trains, Eisenmann proposed
                              a modification to the previously proposed formula to adapt it to the case of high-speed vehicles
                              and lines.
                              Additionally, the formula of Prud’Homme is important because it introduces new criteria and re-
                              veals how the vertical rail track stiffness, the unsprung mass of the vehicle and the quality of the
                              rail track, in addition to the speed of the vehicle, affect the dynamic overloads.
                              As expressed by this formula, for a given speed and rail track quality, different geotechnical and
                              geometric compositions of infrastructure, which determine the stiffness, cause different dynamic
                              overloads. This fact was not considered in the Eisenmann formulation, exposing its limitations.
                              The objective of this article is to analyze these limitations; for this analysis, a threedimensional
                              (3D) finite element model of the rail track will be employed to calculate static and dynamic sti-
                              ffness and obtain the dynamic load values for different types of infrastructure. These results will
                              enable us to analyze the relationship between the strength characteristics of the rail track and the
                              dynamic coefficientC , which is understood to be the ratio between the total dynamic loads and the
                                               d
                              static loads that are transmitted to the rail track.
                              Keywords: high-speed rail, Eisenmann formula, dynamic coefficient, overload, Prud´Homme formula.




                   1  Balmaseda, Lucía. University of Castilla-La Mancha, Spain. Email: Lucia.balmaseda@uclm.es
                     Gallego, Inmaculada. University of Castilla-La Mancha, Spain. Email:  Inmaculada.Gallego@uclm.es
                     Sánchez-Cambronero, Santos. University of Castilla-La Mancha, Spain. Email: Santos.Sanchez@uclm.es
                     Rivas, Ana. University of Castilla-La Mancha, Spain. Email: Ana.Rivas@uclm.es




                   International Congress on High-speed Rail: Technologies and Long Term Impacts - Ciudad Real (Spain) - 25th anniversary Madrid-Sevilla corridor  301
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