Accession Number : AD0617246

Title :   PLASTIC HINGE FORMATION IN REINFORCED CONCRETE BEAMS.

Descriptive Note : Technical rept. for 1 Aug 63-31 Dec 64,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : NORDELL,William J.

Report Date : JUN 1965

Pagination or Media Count : 80

Abstract : Fifteen static and dynamic tests were conducted to measure the actual magnitude of the curvature of a plastic hinge and to correlate the angle of deformation with resistance for beams subjected to dynamic loads. The primary variables were the amount of compression reinforcement, the distance between the concentrated loads, and the rate of loading. The dynamic step loads ranged in magnitude from about 1.10 to 1.25 times the static yield load. The computed values of moment, curvature, and deflection at the onset of plastic hinging were less than the experimental values for both static and dynamic loadings. The 30% increase in beam resistance under dynamic loads agreed with the increase in yield strength of the coupon specimens subjected to rapid straining. Plastic hinging was similar in the static and dynamic beams loaded at mid-span. Crushing occurred at approximately the same deflection under both types of load. For the beams with a pure moment region, a dynamic load equal to approximately 1.1 times the static load caused crushing at mid-span before the plastic hinge had developed as completely as it did for static loading; thus, for dynamic loads, the deflections were lower at the onset of crushing than they were for static loads. (Author)

Descriptors :   *FLEXIBLE STRUCTURES, *PLASTIC PROPERTIES, DEFORMATION, LOADS(FORCES), STATICS, DEFLECTION, MOMENTS, CIVIL ENGINEERING.

Distribution Statement : APPROVED FOR PUBLIC RELEASE