Elastic and Self-Healing Properties of Concrete Including Graded Clinker

In the present work, high-performance concrete including graded clinker-that is, crushed portland cement clinker with a maximum particle size of 1 to 10 mm (0.04 to 0.39 in.) was studied. The investigation was aimed to assess the effects of graded clinker on strength and elastic modulus of concrete as well as the potential use of clinker as a self-healing concrete constituent. It was found that elastic-mechanical concrete performances were highly improved by the inclusion of graded clinker. It was shown by modeling that the elastic properties of the cement matrix were also improved. Concrete shrinkage final values were similar to those observed for the reference concrete, and higher at early ages. Durability indicators also showed values close to or better than those observed for the reference concrete. The self-healing properties were investigated by mechanical testing and microscopic analysis. After recovery in wet air, preliminary loaded samples showed increased regular strength, the presence of hydration products similar to those from clinker hydration in former cracks, reduction hysteresis areas, and residual strain under loading cycles.