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2. 2) Sawaguchi, M.: Soil Constants for Piles, Report of the Port and Harbor Research Institute, Vol. 7, No. 2, pp. 65-94, 1968 (in Japanese).
3. 3) Yoshinaka, R.: The Coefficient of Lateral Subgrade Reaction, Civil Engineering Journal, Vol. 10, No. 1, pp. 32-37, 1968 (in Japanese).
4. 4) Maeda, Y., Tarumi, Y., Oishi, M. and Kurachi, S.: Relationship between the Coefficient of Lateral Subgrade Reaction and the Loading Width by the Horizontal Loading Test in the Hole of the Caisson Type Pile, Proceedings of the 50th Annual Conference of the Japan Society of Civil Engineering, III-480, pp. 960-961, 1995 (in Japanese).
5. 5) Yahagi, K.: Horizontal Bearing Capacity of Piles and Ground Deformation—Relationship between N-value and K-value—, Soil Mechanics and Foundation Engineering, Vol. 25, No. 8, pp. 29-35, 1977 (in Japanese).