Studies on the Yield of Plastic Hinges in Concrete Beams

Abstract

Experimental studies were carried out to investigate the yield of plastic hinges in reinforced and prestressed concrete beams. Eighty-eight simple beams and thirty-two two-span continuous beams were tested under static loading to failure and theoretical analysis was made as to the rotation capacity of plastic hinges and the redistribution of internal bending moments. The rotation capacities of plastic hinges were analysed using the reinforcement index q. To examine the yield of plastic hinges in continuous beams, the measured strengths of beams were compared with those calculated values based on the simple beam tests. Though a prestressed concrete beam does not show any definite yield phenomena, the plastic rotation can also be calculated just as in case of reinforced concrete beams. But the rotation capacities of the former are a good deal smaller than that of the latter. The yield of plastic hinges though partly incomplete, were recognized both in prestressed and reinforced concrete beams.