Title: Repeated Loading Effect on Ultimate Static Strength of Concrete Beams
Author(s): John R. Verna and Thomas E. Stelson
Publication: Journal Proceedings
Appears on pages(s): 743-750
A group of 16 reinforced concrete beams were tested to determine the effect of history of prior loading on their ultimate static strength. All beams were identical except for reinforcing steel which was altered to obtain different modes of failure. The test results show significant increases in beam strength for a few thousand cycles of repeated load if the beam is not susceptible to bond failure. The load levels were such that many cycles (1,000,000 o r more) would have caused a decrease in beam strength of about 40 to 55 percent. Bond failures showed no increase in strength and the most rapid deterioration in strength under cycles of load.