Compressive strength and stiffness of ultra-high performance concrete subjected to transverse tension and cracking

Compressive strength and stiffness of Ultra-High Performance Concrete subjected to transverse tension and cracking. Transverse tension and cracking generally lead to a reduction of compressive strength in reinforced concrete. This could also be confirmed for ultra-high performance concrete (UHPC) in biaxial tests on reinforced concrete panels. The reduction in compressive strength for fine-grained UHPC is already pronounced even with small transverse tensile strains. Besides compressive strength, the compressive stiffness is affected by a reduction due to transverse tension and cracking, too. This can be examined very well on UHPC due to its largely linear elastic behaviour under compressive loading. The addition of steel fibres minimises the reduction of compressive strength as well as compressive stiffness. Overall, the reduction of compressive strength is only little larger for both UHPC reinforced with steel bars only and UHPC reinforced with a combination of steel bars and steel fibres than for normal-strength concrete reinforced in the same manner. Based on the results presented here, a material model for cracked UHPC under compression loading may be developed. © 2019, Ernst und Sohn. All rights reserved.