*Michiharu Ikeda¹, Kakda Kret², Takeshi Tsuji³, Tatsunori Ikeda³, Tomohiro Tsuji⁴, Kozo Onishi⁵, Naoki Nishizaka⁵ (1.Department of Civil Engineering, Shikoku Research Institute Incorporated, 2.Institute of Technology of Cambodia, 3.Kyushu University, 4.Yamaguchi University, 5.Shikoku Electoric Power Co. Inc.)