The behavior of alkali-silica reaction-damaged full-scale concrete bridge deck slabs reinforced with CFRP bars

Abstract

Steel material is susceptible to corrosion after being in an aggressive environment and chemical attacks causing major deficiencies and failure; in some cases, maintenance or repair is necessary. Consequently, carbon fiber-reinforced polymers (CFRP) materials have been innovated to replace the usage of conventional steel reinforcement. In this study, the behavior of reinforced concrete bridge deck slab has been investigated under the effect of ASR damage and internal reinforcement with CFRP bars. However, the effect of the reinforcement type (CFRP and steel), reinforcement ratio (0.38, 0.46, and 0.57) %, and ASR damage stage (without, first, second, and third) has been carried out using the NLFEA technique after a well-calibration process against available experimental data. Generally, it has been noticed that the utilization of CFRP bars significantly improved the slab's strength in compression and tension, stiffness, and modulus of elasticity. Moreover, an innovative and cost-effective reinforcing technique, using CFRP bars with a 0.38% ratio or 0.46% reinforcement ratio, represents an ideal solution to improve the ultimate load-carrying capacity, serviceability, and durability. In addition, CFRP exhibited more strain values in concrete and steel materials and decreased under exposure to ASR damage action. Under exposure to ASR damage action, both the elastic and post-cracking stiffnesses are reduced regardless of the reinforcement type. Generally, it has been observed that the resulting degradation could be approximated by a parabolic shape having a slower decreasing rate at ASR levels of 2 and 3 where the material's losing most of its mechanical properties. Finally, a linearly decreasing relationship was found between the slab's energy capability and ASR level.