1. TOKYO ELECTRIC POWER COMPANY HOLDINGS, Civil & Architectural Engineering Management Office(1-1-3, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100-8560, Japna)
2. JAPAN COAL FRONTIER ORGANIZATION, Technology Development Department(3-2-1, Nishishinbashi, Minato-ku, Tokyo 105-0003, Japan)
3. NIHON UNIVERSITY, College of Engineering, Department of Civil Engineering(1, Tokusadanakagawara, Tamura-machi, Koriyama-shi, Fukushima 963-8642, Japan)