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Abstract. In this paper, a global monitoring system based on the measurement of acoustic emission (AE) due to active deterioration processes is presented. This allows us to examine the entire volume of an element and to locate and identify the type and the dynamics of the deterioration processes under service conditions. The resulting data are used to determine and locate the damage processes that are dangerous in construction made of pre-stress concrete, steel and fiber glass and to assess the general condition of the structure.

In this paper, a global monitoring system based on the measurement of acoustic emission (AE) due to active deterioration processes is presented. This allows to examine the entire volume of an element and to locate (with an accuracy of the measuring zones) and identify the type and the dynamics of deterioration processes under service conditions. The resulting data are used to determine and locate the damage processes that are dangerous in construction and to assess the general condition of the structure as well as the degree of risk.

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Abstract. The study presents the analysis of the process of crack formation and crack width growth in statically determinate and hyperstatic reinforced concrete beams with the IADP acoustic emission method. The beams were subjected to the monotonic, variable with unloading, and variable cyclic loading schemes. The criteria of structural damage were established to account for the structure durability.

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Phenomena occurring during the curing of concrete can decrease its mechanical properties, specifically strength, and serviceability, even before it is placed. This is due to excessive stresses caused by temperature gradients, moisture changes, and chemical processes arising during the concreting and in hardened concrete. At stress concentration sites, microcracks form in the interfacial transition zones (ITZ) in the early phase and propagate deeper into the cement paste or to the surface of the element. Microcracks can contribute to the development of larger cracks, reduce the durability of structures, limit their serviceability, and, in rare cases, lead to their failure. It is thus important to search for a tool that allows objective assessment of damage initiation and development in concrete. Objectivity of the assessment lies in it being independent of the constituents and additives used in the concrete or of external influences. The acoustic emission-based method presented in this paper allows damage detection and identification in the early age concrete (before loading) for different concrete compositions, curing conditions, temperature variations, and in reinforced concrete. As such, this method is an objective and effective tool for damage processes detection.