Effect of different column failures on collapse resistance of T-stub connection substructure
Structural collapse will cause serious casualties and huge property losses,and studying collapse resistance of the structure can provide essential guidance and reference for structural design.Through the finite element numerical simulations on beam-column substructures experiencing different column failure scenarios,the failure mode and resistance mechanism of the structure were deeply analyzed,and the influence of span ratio on collapse resistance of beam-column substructure under corner column failure was discussed.The results show that prior to middle column failure,the load it bears will be transferred to the side column more through the beam connected to the major axis direction of the failed column during the early stages of deformation post-failure.However,during the stages of significant deformation that follow,the load transfer capacity between the major and minor axis directions shows little difference;Under the condition of side column failure,catenary mechanism only occurs in the beam in the symmetrical direction;In the case of corner column failure,the substructure's beams only experienced the stage of bending mechanism;Among the three column failure scenarios analyzed,corner column failure is identified as the most perilous due to the absence of a catenary mechanism in the beam components;In the case of corner column failure,the ultimate load-bearing capacity of beam-column substructure decreases gradually with the increase of span ratio.