Anisotropic Compressive Behaviour of Concrete from Slabs Damaged by Alkali-Silica Reaction

This paper investigates the anisotropy of the compressive strength and stiffness of concrete in ASRdamaged concrete slabs through an in-depth literature review and experiments. Using Digital Image Correlation (DIC), deformations and crack propagation are closely monitored and analysed. The results show that: (i) The vertical compressive strength and stiffness are lower than the horizontal; (ii) the reduction of the vertical strength and stiffness is mainly due to closure of the horizontal ASR-induced macro-cracks and; (iii) the reduction of the horizontal strength and stiffness is mainly due to the presence of ASR-induced micro-cracks in the cement paste. It is found that the load-carrying capacity and the serviceability for ASR-damaged slabs should be assessed based on the horizontal strength and stiffness.