Class A predictions of a NATM tunnel in stiff clay T. Svoboda, D. Maˇ s´ ın 1 and J. Boh´ aˇ c Charles University in Prague Institute of Hydrogeology, Engineering Geology and Applied Geophysics Albertov 6 12843 Prague 2, Czech Republic E-mail: masin@natur.cuni.cz Tel: +420-2-2195 1552, Fax: +420-2-2195 1556 June 23, 2010 Submitted to Computers and Geotechnics 1 corresponding author