전단보강이 없는 순환골재 콘크리트보의 크기효과에 대한 실험적 연구

The authors examined the size effect of reinforced concrete(RC) beams using natural coarse aggregates and recycled coarse aggregates. The specimens were made of concrete with a maximum coarse aggregate size of 20 mm. In this study, depth-to-width ratio, shear span-to-depth ratio, tension steel ratio and RCA replacement ratio were fixed 1.5(i.e., h/b=1.5), 3(i.e., a/d=3), 1.2%(i.e.,p=1.2%) and 30%(i.e., R r =1.2%) respectively. The test variables only include the RC beam size and aggregate type. A total of 10 simple RC beams were tested under four points loading. It has been shown that shear strength decreases as member size increases. This is associated with a phenomenon called size effect. However, the size of the RC beams does not seem to affect the shear strength proportionally. Besides, test results were analyzed and then compared with the findings and various shear design equations. To conclude, the shear equations reflect relatively well with most of experimental data.