Assessment of the TRM reinforcement of windowed masonry walls through OMA identification

Abstract

Masonry constructions compose the majority of the Architectural Heritage worldwide, thus, their preservation is of great importance. Nevertheless, they usually show a great vulnerability to seismic and dynamic loads. Several reinforcement techniques can be used in order to improve their dynamic behaviour. The Textile Reinforced Mortar (TRM) material appears as very suitable, since it meets the requirements of compatibility and reversibility of the retrofitting. Moreover, it avoids some problems related to permeability. And strongly reduces adhesion and debonding issues. In this paper the effectiveness of the TRM reinforcement for dynamic loads for windowed brick masonry walls is evaluated through vibration testing and operational modal analysis. To this aim, two scaled brick masonry walls were built at the “Laboratorio de Grandes Estructuras” of the University of Alicante. Only one of them was reinforced with the TRM. Both were damaged with a cyclic in-plane lateral force for simulating damage due to seismic actions. Structural vibrations of the two walls were measured in the presence of a white noise excitation. Modal parameters were evaluated through Operational Modal Analysis (OMA) before and after the damage. Finally, changes in modal parameters due to damage were compared and investigated in both the unreinforced and reinforced cases. The results suggest that TRM reinforcement can be considered effective for improving the mechanical behaviour of a brick windowed masonry wall.