1. Professor, Dept. of Urban and Civil Engineering, Ibaraki Univ., Nakanarusawa 4-12-1, Hitachi 316-8511, Japan.
2. Professor, Dept. of Mechanics and Civil Engineering, Jinan Univ., Guangzhou 510632, P. R. China.
3. Professor, Dept. of Earth Resources Engineering, Kyoto Univ., Kyoto City, 606-8501, Japan.
4. Nippon Steel Composites Co., Ltd., Nihonbashukobuna-cho Cho-ku 3-8, Tokyo 103-0024, Japan.