Increasing loading frequency: effects on railways platforms materials
Autor/es
Lamas López, Francisco; Cui, Yu-Jun; Dupla, Jean-Claude; Canou, Jean; Tang, Anh-Minh; [et al.]Fecha
2014-04-08Tipo de documento
conferenceObjectMateria/s Unesco
3323 Tecnología de Los Ferrocarriles1209.03 Análisis de Datos
2511.12 Física de Suelos
Resumen
The aim of this paper is to present the influence of increasing train
speed on the behaviour of conventional railways lines’ interlayer (ITL). In France,
there are more than 30000 kilometers of operational conventional lines under
exploitation. The main characteristic of these lines lies in the existence of an
intermediate layer over the subgrade soil and under the ballast layer. This coarse soil
is mainly the product of the interpenetration of ballast and subgrade soil. In some of
the conventional lines, problems of stability could be expected if the train speed is
increased. These problems are characterised by significant displacements of
platforms. The behaviour of this interlayer soil has been studied using a large-size
cyclic triaxial set up (300 mm diameter specimens). We first propose an appropriate
method of sample fabrication. Then, typical results are presented corresponding to a
triaxial test carried out on a ITL soil, in which the loading frequency has been
increased. To simulate an increase of train speed, different loading frequencies have
been used (corresponding to speeds of about 80 km/h – 160 km/h - 220 km/h). The
vertical load applied on the specimen simulates the “M” load produced by the bogies
of the carriages.