1. Ecole des Ponts ParisTech, U.R. Navier/CERMES, 6-8 Av. Blaise Pascal, Cité Descartes, Champs-sur-Marne, 77455 Marne-la-Vallée Cedex 2, FR.
2. Professor, Ecole des Ponts ParisTech 6-8 Av. Blaise Pascal, Cité Descartes, Champs-sur-Marne, F-77455 Marne-la-Vallée Cedex, FR (Corresponding author), e-mail: yujun.cui@enpc.fr
3. French Railway Company (SNCF), Civil Engineering, 6 Av. F. Mitterrant, 93574 La Plaine St. Denis, FR.