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Experimental and Analytical Studies on the Hysteretic Behavior of Reinforced Concrete Rectangular and T-Beams.
Ma, S. Y. M.; Bertero, V. V.; Popov, E. P.
National Science Foundation, Washington, D.C., May 1976, 264 p.
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This report describes an experimental and analytical study program carried out for investigating the inelastic behavior of critical regions that may develop in a beam near its connection with the column of a reinforced concrete ductile moment-resisting space frame when subjected to severe earthquake excitations. In the experimental program, a series of nine cantilever beams, representing half-scale models of the lower story girder of a 20-story ductile moment-resisting reinforced concrete office building, was designed according to present seismic codes. These beams were designed in order to study the effects of (1) the slab by testing T-beams with a top slab width equal to the effective width specified by the ACI (318-71) Code; (2) relative amounts of top and bottom reinforcement by varying the amounts of bottom reinforcement; (3) supplementary ties by providing hairpin ties around main bars not restrained by the corners of stirrup ties; (4) the high shear force by varying the shear-span ratio; and (5) loading histories by testing some beams under loading reversals inducing a gradually increased deformation, and others, under monotonic loadings to large deformations in one direction. Detailed descriptions of the specimens, testing procedures, experimental data, and results obtained are presented. The significance of the experimental results in relation to the seismic design of the reinforced concrete critical region is also discussed.
Earthquake resistant structures; Reinforced concrete; Mechanical hysteresis; Finite element analysis; Buildings; Earthquake engineering; Ground motion; Box beams; T beams; Shear stresses