Earth concrete under cyclic loadings: Stress-strain curves and damage assessment by means of acoustic emission and digital image correlation techniques

Cyclic compressive tests were conducted on recycled sand (RS) earth concrete mixtures of different amounts of clay conserved previously at wet and dry curing conditions (relative humidity (RH) = 90% and 50%, respectively). The loops of the stress-strain curves were analyzed. In addition, Kaiser Effect investigation and acoustic emission (AE) damage assessment were carried out. The evaluation showed a successful correlation between the AE indices and cracking progression which was captured by means of digital image correlation (DIC) technique. The results reveal that Kaiser Effect was achieved at wet curing condition whereas it was not attained at the dry one. The RS specimen of highest clay content at dry curing condition demonstrated the highest degree of damage. In line with the journal's aims and scope and as a novelty, this paper finally examines Kaiser Effect by means of DIC. The results revealed that this aspect which is known to be linked with damage occurrence is not necessarily affected by the evolution of crack width.