In this paper we investigate the influence of the shape and of the size of the specimens on the compressive strength of high strength concrete. We use cylinders and cubes of different sizes for performing −6 −1 stable stress-strain tests.…
In this paper we investigate the influence of the shape and of the size of the specimens on the compressive strength of high strength concrete. We use cylinders and cubes of different sizes for performing −6 −1 stable stress-strain tests. The tests were performed at a single axial strain rate, 10 s . This value was kept constant throughout the experimental program. Our results show that the post-peak behavior of the cubes is milder than that of the cylinders, which results in a strong energy consumption after the peak. This is consistent with the observation of the crack pattern: the extent of micro-cracking throughout the specimen is denser in the cubes than in the cylinders. Indeed, a main inclined fracture surface is nucleated in cylinders, whereas in cubes we find that lateral sides get spalled and that there is a dense columnar cracking in the bulk of the specimen. Finally, we investigate the relationship between the compressive strength given by both types of specimen for several specimen sizes.