The tensile strength of concrete plays a vital role in the design of large concrete infrastruc- tures. Further, the majority of these structures are subjected to cyclic loading, causing fatigue. Most of the properties under monotonic and fatigue loadings are…
The tensile strength of concrete plays a vital role in the design of large concrete infrastruc- tures. Further, the majority of these structures are subjected to cyclic loading, causing fatigue. Most of the properties under monotonic and fatigue loadings are obtained from tests conducted on small- sized specimens. Since concrete exhibits a strong size effect due to its heterogeneous nature, it is imperative to determine the properties of large specimens. This study aims to conduct a stable, direct tension test on 400 x 400 x 100 mm sized concrete prismatic specimens to investigate the differences in fracture mechanism under both monotonic and fatigue loading. The acoustic emission (AE) and digital imaging are used to capture the evolution of microcracking during the monotonic and fatigue tests. It is observed that the tensile strength of concrete is about 4-5% of the characteristic compres- sive strength, which is nearly half of the value considered in the literature. Further, the mechanism of microcracking is significantly different under monotonic and fatigue loadings.