This paper presents an experimental study on effect of specimen size on the static strength and dynamic increase factor (DIF) of plain and fiber reinforced high-strength concrete determined from Split Hopkinson pressure bar (SHPB) tests.
Four types of specimens were used to determine the static strength of the concrete including (i) cylinders with the same size as that used for SHPB test (diameter (D)=77 mm and length (L)/D ratio=0.5), (ii) cylinders with the same diameter as that of SHPB but with L/D=2, (iii) standard cylinders of D100×200-mm, and (iv) 100-mm cubes.
Results indicate that cylinders with the same diameter as those of the SHPB but with L/D=2 are suitable for determining the static strength to be used in DIF computations based on the stress state and failure patterns.