EXPERIMENTAL STUDY ON COLLAPSE BEHAVIOR OF WEAK-BEAM PLANAR FRAME SUBJECTED TO REPEATED HORIZONTAL LOADING : Part II Growth phenomena of bow-shaped deformation mode and drift of sway-mode vibration center under dynamic loading

Abstract

Growth phenomena of bow-shaped deformation mode in multistory multihay weak-beam-type planar frames has been predicted by symmetry limit theory and equilibrium path bifurcation theory. To verify the validity of the theoretical prediction of the bow-shaped mode appearance, static and dynamic loading tests on the 3-story I-span miniature model frame of weak-beam-type have been carried out. In the previous article, Part I, the results of the static loading tests were presented. The prediction method for the bow-shaped mode appearance was verified and the characteristics of the collapse behavior of the frame under repeated loading were clarified. In the present article, Part II, the results of dynamic loading tests are presented. The dynamic collapse process of the frame including bow-shaped mode appearance and the drift of vibration center is examined in detail through the comparison of the results of the test specimens under various loading conditions. The validity of the two prediction methods for the bow-shaped mode appearance and the drift appearance in sway-mode vibration center is verified.