FINITE ELEMENT ANALYSIS OF CES COMPOSITE COLUMNS

New composite structural systems consisting of only steel and concrete, the concrete encased steel (CES) structures, have been developed in Japan to simplify and reduce the cost in construction works for SRC structures. An experimental study on CES column using fiber reinforced concrete (FRC) panel and CES column without concrete cover (CES core column) have been carried out by one of the authors to investigate the seismic performance of the columns. In this paper, a detailed three-dimensional (3D) nonlinier finite element model is delevoped to study the response and predict the seismic performance of CES composite columns subjected to constant axial and lateral cyclic loads. The columns are modeled using solid elements and analyzed by using finite element program, ANSYS APDL v.14, to investigate the structural performance of the CES columns, which is compared with the experimental results. Numerical results show that CES using FRC panel and CES Core columns had excellent seismic performance with a stable spindle shape hysteresis characteristic and less damage. The presence of FRC panel contributed to flexural capacity about 40% in maximum. In general, the analytical results obtained from the finite element analysis are able to accurately simulate the behaviour of the CES composite columns on the experimental study.