1. Professor, Dept. of Civil Engineering and Architecture, Muroran Institute of Technology, Muroran 050-8585, Japan (corresponding author).
2. Research Associate, Dept. of Civil Engineering and Architecture, Muroran Institute of Technology, Muroran 050-8585, Japan.
3. Senior Researcher, Sumitomo Mitsui Construction Co., Ltd., Nagareyama 270-0132, Japan.