NUMERICAL INVESTIGATION ON PERFORMANCE OF A PRECAST COLUMN- TO-FOUNDATION CONNECTION UNDER QUASI-STATIC CYCLIC LOADING

During past earthquakes, precast structures designed only for the gravity loads have subjected to extensive damages due to inadequate connections between the beams and the columns, and many of the columns have failed at their bases. This problem gave researchers incentive to examine the performance of the existing column-to-foundation systems under cyclic loading. However, this study is limited to investigate the seismic response of a particular type of column-foundation system through steel column shoes and anchorage bolts proposed by the Peikko Group for the gravity load carrying system. The main objective of this study is to simulate the response of this particular column-to-foundation system numerically under a quasi-static loading and compare the response with the experimental response. For this purpose, a numerical model is developed using MIDAS finite element programme. The strength, the loading and unloading stiffness and the pinching phenomenon are the key parameters used to validate the accuracy of the numerical model. From results of the numerical model, significant degradation in the stiffness and the energy dissipation are observed as increasing of the ductility of the system. The reduction of energy dissipation capacity is mainly due to the pinching phenomenon.