1. 1) Cabinet Office, Government of Japan: http://www.bousai.go.jp/jishin/chubou/nankai/14/ , 2003.
2. 2) Japan Road Association: Specifications for road earthworks, slope stability, 1999a (in Japanese).
3. 3) Japan Road Association: Specifications for road earthworks, retaining wall, 1999b (in Japanese).
4. 4) Public Works Research Institute: Standard design, No. 2, retaining walls, 2000 (in Japanese).
5. 5) Okamura, M., Mihara, A., Takemura, J. and Kuwano, J.: Effects of footing size and aspect ratio on the bearing capacity of sand subjected to eccentric loading, Soils and Foundations, Vol. 42, No. 4, pp. 43-56, 2002.