1. PhD Research Fellow, DISTART-Univ. of Bologna, VialeRisorgimento 2, 40136 Bologna, Italy. E-mail: barbara.bonfiglioli@mail.ing.unibo.it
2. Associate Professor, DISTART-Univ. of Bologna, VialeRisorgimento 2, 40136 Bologna, Italy. E-mail: giovanni.pascale@mail.ing.unibo.it
3. PhD Candidate, Instituto Eduardo Torroja de Ciencias de laConstrucción, IETcc-CSIC, Serrano Galvache s/n, 28033 Madrid, Spain. E-mail: smdemingo@ietcc.csic.es