1. Graduate School of Science and Technology, Niigata University, Niigata, Japan
2. The Civil Engineering Research Institute for Cold Region, Sapporo, Japan
3. Research Institute for Natural Hazards & Disaster Recovery, Niigata University, Niigata, Japan
4. Faculty of Engineering, Niigata University, Niigata, Japan
5. Faculty of Science, Niigata University, Niigata, Japan