Cracks in concrete structures can serve as pathways for aggressive
chemical substances that can lead to a progressive deterioration of the
cement stone as well as of the reinforcement, affecting the load
capacity, service life and useability of concrete structures. However,
concrete and reinforced concrete exhibit an intrinsic ability to heal
cracks, defined as autogenous self-healing. This effect includes the
precipitation of calcium carbonate in the presence of water and CO2 and
is accompanied by continued hydration, swelling and mechanical blocking
of the crack pathway. Experiments led to the inclusion of crack healing
by autogenous self-healing in Eurocode 1992-3 for water retaining
concrete structures. However, despite code restrictions, autogenous
self-healing of concrete shows limited effectiveness in practice. This
indicates the need for further research to provide engineers with
reliable design rules. Therefore, this study aims for giving a broad
literature review on the state-of-the-art knowledge on autogenous
self-healing, the boundary conditions, consensus and controversy of
processes and factors influencing the efficiency of autogenous
self-healing. Regarding the transferability of laboratory results to
real concrete constructions, materials, crack initiation techniques,
experimental concepts and methods for assessing the effectiveness of
autogenous self-healing are discussed and recommendations for future
experiments are set.