Performance of recycled concrete beams under sustained loads coupled with chloride ion (Cl−) ingress

- Long-term coupled damages of sustained loads and Cl− ingress were applied.
- Load-induced cracking of recycled aggregate concrete (RAC) beams was acceptable.
- Corrosion-induced cracking of RAC beams was much more serious.
- Flexural capacity of RAC beams was comparable with that of natural concrete ones.
- Poorer durability of RAC beams serving in severe conditions should be considered.

This paper presents the experimental results of the cracking propagation and flexural performance degradation of reinforced concrete beams with recycled aggregates (RA), under long-term coupled effects of sustained loads and chloride ion (Cl−) ingress. Test results show that the load-induced cracking damages of recycled aggregate concrete (RAC) beams were slightly lower while the corrosion-induced cracking damages were larger than the natural aggregate concrete (NAC) beams, through the 20-month coupled damage history. The flexural capacity was found comparable among damaged beams with different RA replacements. Therefore, this paper suggests the mechanical properties of RAC beams should be acceptable, given that they served under sustained loads and the corrosion of the longitudinal reinforcements was relatively low (less than 3%). However, RAC beams' inferior durability against cracking by steel bar corrosion should be considered with great cautious.