Flexural Analysis Combined with Freeze-thaw Depth for Reinforced Concrete Beams and Columns

Abstract

This study presents a kinematic model for flexural analysis of RC beams and columns subjected to freeze-thaw action based on upper bound theorem. The developed model enables analytical derivation of the contribution of damaged concrete when actual deterioration profile is idealized as an assemblage of undamaged and damaged zones based on freeze-thaw depth obtained from concrete core specimens. The accuracy of the analysis is verified by comparing its predictions with available 21 RC columns and beams failing in flexure after freeze-thaw exposure. The predicted results show good agreement with the test results within error of 6% on average. Thereafter, the developed analysis predicts the ultimate moment capacity of a RC beam, which was taken from an existing bridge slab replaced because of the combined effect of frost damage and fatigue. Results demonstrate that the present analysis could support a rational decision-making regarding the need for repair or rehabilitation. This paper is the English translation from the authors’ previous work [Kanazawa, T., Nakamura, T., Sakaguchi, J. and Kawaguchi, K., (2021). “Flexural analysis combined with freeze–thaw depth for RC linear members.” Journal of Japan Society of Civil Engineers, Ser. E2 (Materials and Concrete Structures), 77(4), 177-186. (in Japanese)].