Experimental Study of Seismic Response of R.C. Setback Buildings

摘要

A 1/4-scale model of a two-bay, six-story reinforced concrete ductile moment resisting frame having 50 percent setback at the mid-height was designed, constructed, and tested. The prototype structure was designed for combined gravity and seismic effects determined according to the requirements of the 1982 Uniform Building Code. Proportions and details were provided to satisfy the seismic provisions of the ACI Building Code and the ACI-ASCE Committee 352 recommendations for design of beam-column connections. The test structure was subjected to a number of tests including static pull-back tests, free-vibration tests, and unidirectional and bidirectional earthquake simulations. The experimental findings from the response of the test structure were extended to a broad spectrum of response of setback frames. The report documents design, construction and testing of the model. Interpretations of the measured response are presented. Correlations obtained from three-dimensional elastic analysis and two-dimensional inelastic static and dynamic analyses are presented. Current provisions for seismic design of ductile reinforced concrete structures are evaluated. A building can be identified. A static analysis technique is proposed for design of setback structures.