1. Member, ASCE
2. Assoc. Prof., Dept. of Civ. and Envir. Engrg., Univ. of Perugia, Perugia, Italy. E-mail: brunone@unipg.it
3. Prof., Dept. of Civ. Engrg., Univ. of Toronto, Toronto, ON, Canada M5S 1A4; corresponding author. E-mail: karney@civ.utoronto.ca
4. Res. Assoc., Dept. of Civ. and Envir. Engrg., Univ. of Perugia, Perugia, Italy.
5. Asst. Prof., Dept. of Civ. and Envir. Engrg., Univ. of Perugia, Perugia, Italy.