Gerardo Grelle (a), Laura Bonito (b), Paola Revellino (b) & Giuseppe Sappa (a)
(a) Department of Civil and Environmental Engineering, University of Rome "La Sapienza" via Eudossiana, 18 - 00184 Rome E-mail: gerardo.grelle@uniroma1.it
(b) Department of Science and Technologies, University of Sannio, via Dei Mulini 59/A - 82100 Benevento.