NUMERICAL MODEL FOR DETERIORATION BEHAVIOR CAUSED BY LOCAL BUCKLING OF COLD PRESS-FORMED SQUARE HOLLOW SECTION COLUMNS

* ** *** **** Nikken Sekkei LTD., M. Eng. (The Former Grad. Stud. of Kyoto Univ.) Assoc. Prof., Dept. of Architecture and Architectural Engineering, Kyoto Univ., Dr. Eng. Assist. Prof., Dept. of Advanced Engineering, Nagasaki Univ., Dr. Eng. Grad. Stud., Dept. of Architecture and Architectural Engineering, Kyoto Univ. In order to simulate deterioration behavior of cold press-formed square hollow section (SHS) columns, procedure to build up numerical model, called as multi-spring model, is proposed in this paper. Following regulations are considered for modeling; differences of material properties between flat area and corner area, hysteresis curve after local buckling, and transformation of plastic deformation considering with equivalence of plastic dissipation energy in the entire either