抄録
Cumulative plastic hinge rotations of framed structure subjected to alternating displacement, such as seismic disturbance, are presented in analytical expressions, and based on the analytical solutions, fundamental behaviors of cumulative deformation in the plastic hinges with non-hardening and hardening characteristics are discussed. The following features are pointed out. (i) Plastic hinge rotations in the frame with non-hardening hinge characteristic are accumulated lineraly with repetition of cycles under constant dislacpement amplitude. (ii) For hardening plastic hinge, cumulative rotations increase exponentially with alternating cycles and converge tosteady state after sufficient cycles. (iii) Final converged value of cumulative rotation depends substantially on the hardening characteristic of m-θ_p hysteresis. In the larter part of the paper a few comments on cumulative damage under random vibratlon are added.
