Abstract:A steel reinforced concrete (SRC) column is a combined specimen constructed by allocating steel in the reinforced concrete in order to bear the external force. Because the SRC column gains the advantages of high strength and stiffness, good ductility, and fine refractoriness, it is widely used in high-rise structures nowadays. From the mixture of steel and reinforced concrete, the force performance and failure mode of the SRC column become more complex than ordinary columns. In this paper, in order to study the numerical simulation methods of the seismic performance of mega SRC columns, based on the finite element software OpenSees, tests on five mega SRC column specimens with different and complex steel sections were carried out under low cyclic reversed load by using the fiber element. Then, the numerical simulation results were compared to hysteretic and skeleton curves. The results indicate that the finite element model based on the fiber element can efficiently simulate the hysteresis response of mega SRC columns, which verifies the rationality and reliability of the numerical model. Meanwhile, a new high-performance multi-layer shell element was used in order to accurately analyze one of the mega SRC column specimens. By comparison to experimental results, the multi-layer shell can adequately simulate the initial stiffness and peak bearing capacity of the specimen. By comparison to the simulation results of the fiber element model, it was found that using fiber element could better simulate the descent of the specimen's bearing capacity, and the results were rather more accurate and efficient.
