AVERAGE STRESS-AVERAGE STRAIN RELATIONSHIP OF STEEL IN UNIAXIAL TENSION MEMBER IN POST-YIELD RANGE

Uniaxial tensile tests were conducted on prismatic reinforced concrete specimens. Stress distribution along bar in addition to the total elongation was measured and average stress-average strain relationship of steel in post-yield range was obtained. In the average stress-average strain curve, steel starts to yield below its yield strength and the length of yield plateau is zero.The average stress-average strain curve can be predicted by assuming a stress distribution of steel. Instead of assuming a bond stress versus slip relationship or the bond stress distribution, the stress distribution was assumed directly. The stress distribution can be simply expressed by sine curve.