Un indice d'endommagement local pour l'évaluation de murs en maçonnerie confinée sous chargement latéral cyclique

The use of a damage index based on stiffness degradation is proposed for the characterization of confined masonry walls submitted to lateral cyclical loads. The damage index, based on the degradation of the lateral stiffness, varies according to the deformation level of the wall. A simplified methodology is presented to estimate the wall behavior using the finite element method. The use of an m parameter is proposed, adjusted through available experimental data of nine natural-scale walls made of hollow bricks, in order to approximate lateral stiffness in each load cycle. With the suggested m value of 0.93, the stiffness of tested walls was predicted, with an average error of 17%. The damage index was estimated with an average error of 15%. Although the results are satisfactory, it is nevertheless necessary to calibrate the value m for other types of masonry.