Initial Investigations on Stress Redistributions Between Different CFRP Reinforcement Types

Carbon fibre reinforced polymer (CFRP) reinforcements are available as meshes, bars or seven-wire strands. These common types exhibit different bond properties depending on the manufacturer, and they display linear elastic material behaviour until rupture, without yielding under tensile loading. As a result, the use of multiple CFRP types within the same concrete cross-section can lead to varying stress and strain states due to cracking and stress redistributions. Given the lack of plasticity in CFRP reinforcements, avoiding premature failure is critical. To investigate this in reinforced (grid and a rebar) member, bond tests and uniaxial tensile tests were performed. Fibre optic sensors were used to monitor and demonstrate the resulting stress redistributions. © fédération internationale du béton (fib).