A computational method for performing nonlinear adaptive pushover analysis of structures through abaqus simulation

A computational method which uses the nonlinear adaptive static (pushover) analysis to evaluate the static force-deformation response of a planar moment resisting frame (MRF) is presented. The MRF considered in this study is a seismic-resisting frame of a prototype five-storey five-bay steel building structure designed based on the Japanese seismic design code. The frame model is simulated by the finite element software ABAQUS. Failure on members is captured by adopting shell elements for beams and columns combined with a refined meshing. The lateral force distribution is adapted during the pushover analysis according to the first eigenmode of the structure by utilizing a novel inverse optimization algorithm. A new stop analysis criterion is introduced that overcomes the numerical difficulty of the available static-solution algorithms to terminate the analysis in the degrading region of the load-deformation response. The effects of load distribution and first (fundamental) small strain eigenperiod on the force-deformation pushover curve are studied. The monotonic adaptive pushover procedure is implemented using the programming language MATLAB. The new tool effectively combines the advanced modeling and analysis capabilities of ABAQUS with the programming simplicity of MATLAB, thus leading to a user-friendly environment. The last offers a robust implementation of pushover analysis and superior numerical results can be obtained, especially the descending branch of the pushover curve and collapse mechanism.