1. Member, ASCE
2. Lect., Res. Inst. of Engrg. Struct., Coll. of Civ. Engrg., Tongji Univ., 1239 Siping Rd., Shanghai 200092, P. R. China. E-mail: wuxhan@online.sh.cn
3. Prof., Dept. of Arch., Grad. School of Engrg., Univ. of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. E-mail: otani@sake.t.u-tokyo.ac.jp
4. Assoc. Prof., Dept. of Arch., Grad. School of Engrg., Univ. of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. E-mail: shiohara@rcs.arch.t.u-tokyo.ac.jp