1. Professor, Federal Univ. of Bahia, Polytechnic School, Dept. of Construction and Structures, Rua Aristides Novís, 02, 5º andar, Federação, Salvador, BA 40210-910, Brazil (corresponding author).
2. Professor, Federal Univ. of Bahia, Polytechnic School, Dept. of Construction and Structures, Rua Aristides Novís, 02, 5º andar, Federação, Salvador, BA 40210-910, Brazil.