Self-healing capacity of concrete with crystalline additives: Natural vs. accelerated exposure conditions

The presence of cracks may significantly affect the life-cycle of structures, as a results of its influence on the designed structural response vs. persistent or even severe accidental load and exposure conditions, when requested. Repairing damaged concrete in existing structures needs important investments to recover the pristine level of serviceability and extend their designed service life. In this respect, the ability of cementitious composites to “self-repair” the cracks, because of autogenous or suitably engineered mechanisms, is a challenging opportunity, making concrete more and more attractive in future sustainable developments of civil engineering. In this study a methodology will be presented to assess the aforementioned capacity, based on three point bending tests on un-cracked and pre-cracked beams, upon exposure to suitable environmental conditions. The paper will focus on the difference between accelerated exposure, in a climate chamber, and “natural conditioning” in air; comparison with immersion in water will also be performed.