1. D.I.S.T.A.R.T., Bologna Univ., Viale Risorgimento 2, 40126 Bologna, Italy (corresponding author).
2. Dept. of Hydraulic and Environmental Engineering, Norwegian Univ. of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
3. D.I.S.T.A.R.T., Bologna Univ., Viale Risorgimento 2, 40126 Bologna, Italy.
4. Dept. Building and Infrastructure, SINTEF, N7465, Trondheim, Norway.