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[en] Highlights: • New cracks develop if a rigid polymer is used to heal a crack, as it transfers the stress to adjacent areas. • Polymers with high elongation (> 100%) and modulus of elasticity much lower than 10 MPa are required for moving cracks. • A polymer with high modulus of elasticity used as healing material also results in detachment from the crack walls. • A burst of acoustic events including high energy emissions can be used to monitor failure if brittle fracture is present. • Digital image correlation allowed precise detection of brittle failure under an increasing crack movement. A study was performed to assess the fitness of continuous monitoring methods to detect failure due to excessive strain on polymers bridging moving cracks in the context of self-healing concrete. Testing of several polymer precursors with distinct properties also allowed conclusions regarding the requirements for polymers in this application. Acoustic emission (AE) analysis was performed in parallel with digital image correlation (DIC) at the macro-scale. In addition, a micro-scale study was performed with tensile tests inside an SEM chamber. Detection of failure through AE analysis coupled with DIC was possible only in case of failure due to brittle fracture of a rigid foam after 9% strain, which generated high-energy acoustic events. Direct observation of interfaces with SEM in-situ loading allowed determination of failure of a rigid foam due to cracking of the polymer matrix and detachment at the interface with the cementitious matrix, with an onset at 5% strain and complete detachment at 16% strain. For a flexible, continuous film of polymer, detachment occurred before 50% strain. Assuming adequate adhesion, polymers with high elongation (> 100%) and modulus of elasticity much lower than 10 MPa are required if cracks subjected to a realistic amplitude of movement are targeted.