A simplified mechanical model to assess the bearing capacity of masonry walls: Theory and experimental validation

Abstract

This paper deals with the bearing capacity of masonry walls under lateral loads. Four different series of experimental measures have been collected, representing a total number of 20 walls tested at the Scientific and Technical Center for Buildings (CSTB, France). The constitutive materials of the walls and the geometrical features of the walls are: – Orthotropic blocks (masonry or concrete units), with either horizontal or vertical cells. Their geometrical dimensions are such that the thickness is either equal to 0.2 m or 0.38 m while the ratios (height/length) range from 0.4 up to 1. The compressive strength of the blocks are in relative ratios (horizontal/vertical strengths) ranging from 0.11 up to 3.11. – Joints made of mortar or thin layer mortar. The vertical joints might be either empty or full while the horizontal joints are full for the whole experiments reported herein. – Walls with lengths ranging from 1 m up to 3.75 m while the height range from 2.5 m up to 2.8 m. An existing model, relying on the principle of wall failure by its diagonal in compression, has herein been applied and its results have been compared with the experimental values for the 20 available walls. The model for compressive diagonal provides results that range within the interval (0.52 up to 2.67) times the experimental bearing capacity of the masonry walls. The authors have therefore developed a simplified model that assumes that the wall fail by induced tension in the perpendicular direction of the diagonal of either the blocks or the walls. Compared to the experimental values collected in this paper, this simplified mechanical model provides theoretical bearing capacity values that are in good accordance with the observed values.