철근콘크리트 휨부재의 피로특성에 관한 실험적 연구 = An Experimental Study on Fatigue Characteristics of Reinforced Concrete Flexural Members

다국어 초록 (Multilingual Abstract)

In recent years, considerable interest has developed in the fatigue strength of reinforced concrete members subjected to cyclic loading for the wide-spread adoption of ultimate strength design procedures, the higher strength materials and the new recognition of the effect of repeated loading on structures such as bridges, concrete pavements and offshore structures.
In this study, a series of experiments is carried out to investigate the fatigue characteristics of deformed bars and underreinforced simply supported beams, The 69 reinforcing bar specimens with grade SD30 and designation of D16, D22, D25, and 24 beam specimens with D16 bars are prepared for this study.
From these series of tests, it is found that ⅰ) the decrease of the bar diameter results in increased fatigue life, ⅱ) the fatigue life of the bars embedded as main reinforcement within a concrete is longer than that of bars in the air. ⅲ) the fatigue strength of beams at ?? cycles with steel ratio of 0.61% and 1.22% is 64.5% and 63.2% of the yielding strength, respectively.
It is concluded that the low steel ratio has no significant effect on fatigue strength of underreinforced beams and the fatigue life underreinforced concrete beams can be predicted conservatively by the fatigue life of reinforcing bar.