ABSTRACT
This chapter focuses on the simple overturning mechanism of a masonry wall, weakly connected to sidewalls, in order to highlight the role of friction at the activation of the mechanism in comparison with other systems of strength in masonry buildings, such as tie-rods and simply supported horizontal diaphragms. The failure mode is identified a priori, by considering two vertical cracks along the corners, where frictional resistances can take place. The actual activation of the frictional resistances is strictly related to the type of mechanism that might occur, being zero for pure rocking failure and maximum when pure sliding takes place. The influence of the frictional resistances due to interlocking between orthogonal walls on the activation load multiplier was evaluated through the variation of the friction coefficient and unit aspect ratio. The frictional resistance due to the presence of a simply supported horizontal diaphragm also favourably affect the horizontal load multiplier.
