1. Professor, Dept. of Civil Engineering, Nagoya Institute ofTechnology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan. E-mail: goto@kozo4.ace.nitech.ac.jp
2. Research Associate, Dept. of Civil Engineering, Toyota NationalCollege of Technology, 2-1 Eisei-cho, Toyota 471-8525, Japan. E-mail: kawan@toyota-ct.ac.jp