Experimental research on compressive performance of ultra high toughness cementitious composites.

Experimental research on compressive property of ultra high toughness cementitious composites (UHTCC) at different ages with three cylinder and cube specimens in each group was carried out. The influences of different fiber type, ages and specimen shape on compressive performance of UHTCC were studied, and the axial compressive stress-strain full curves and performance rule of different specimens were obtained. The results show that the peak strain of cylinder specimen at 28 d age is 0. 015, which is higher than that of normal concrete ( it is 0. 002). The ultimate strain is 0. 034, which is 10 times higher than concrete. And the axial compressive stress-strain full curves of UHTCC with 7 d age have a slowly decreasing process when the stress reaches the peak value, which shows that UHTCC has good compressive toughness then. Deformation performance of UHTCC reduces and compressive strength increases along with the growth of the age. The deformation performance of specimens with ordinary high-strength PVA fiber is lower than that of specimens with K-II REC15 PVA fiber, but the compressive strength of the former is higher than that of latter. The cube compressive strength of specimens is generally higher than that of cylinder specimens with the same age, which indicates that the compressive strength is influenced by the size and shape of specimens. [ABSTRACT FROM AUTHOR]