Affiliation: | (1) Centro de Estudios y Experimentación de Obras Públicas (CEDEX), Madrid, Spain;(2) M2i (Math. Model. Eng. Group), Department of Applied Mathematics, ETS Ingenieros de Caminos, UPM Madrid, Spain;(3) ENUSA, Madrid, Spain;(4) ADIF (formerly at CEDEX), Madrid, Spain;(5) Univ. Bologna, Italy |