Performance of pre-cracked beams exposed to corrosion environment cast with ultra-high performance concrete

Abstract

Ultra-high-performance concrete (UHPC) is a unique type of concrete that has a lot of advantages in the construction sector. There is no risk for reinforced UHPC elements in an aggressive environment or coastal region, unless cracking occurs due to extra-loading or inaccurate structural design. For that, there is a need for this study to be considered. The core concentration of this study is towards understanding the shear behavior of pre-cracked beams cast with UHPC as affected by durability. This program presents materials used to reach the main aim of the present study. 72 specimens were conducted to study UHPC physical and mechanical properties to be compared with traditional normal concrete (NC). Moreover, 10 RC beams were cast to investigate the shear behavior of RC-UHPC beams with dimensions of 100 mm, 150 mm, and 1300 mm. Five non-exposure beams and five exposure beams were corroded by an accelerated corrosion cell, and half the potential cell readings were recorded. Obtained results for specimens provide that; UHPC eliminates deflection with high modulus of elasticity, in chloride penetration test UHPC is 200 times less than NC, and the reduction in bond strength test after corrosion exposure is 66.24 % and 1.69 % for NC and UHPC specimens, respectively. For pre-carking UHPC beams at 80 % of experimental ultimate load; cracking resistance for un-corroded beams exceeds the corroded beams by 250 %. The residual flexural capacities for corroded beams pre-cracking up to 80 % of E.U.L. are 61.6 % and 119 % for NC and UHPC beams, respectively. UHPC is much better than NC in corrosive environments.

Keywords

• UHPC
• Pre-cracked beams
• Accelerated corrosion
• Tension reinforcement corrosion
• Flexural shear cracks