Numerical investigation of crack propagation at openings in unreinforced masonry walls subject to in-plane vertical loads.

Abstract

This research aims to conduct a numerical investigation into the crack propagation behaviour of un-reinforced masonry walls with openings under in-plane vertical loads. The study focuses on analysing the influence of various factors, including opening size, position, and length-to-width ratio, on crack initiation, propagation, and ultimate failure of masonry walls. We modelled a wall using Abaqus software for which the geometry and material properties were adopted from an already carried out experiment. Validation of the software was by comparing load-displacement curves before the parametric studies were carried out. We discovered that walls with larger openings (20%) failed at lower loads compared to those with smaller openings (10% and 15%), and that cracks were mostly likely to form at the top corners of the opening and the part of the wall above the top opening for all opening. The smaller aspect ratio (1/3) failed under much lower stresses, but with failure patterns that were identical to those of the opening sizes. Finally, compared to the bigger size aperture (10%) put at the top left and right corners of the wall, the smaller size openings (5%) required higher loads to fail but with cracks likely to appear in the same locations as that of the opening size and this could be as a result of the nature of loading. Basing on the findings, we then recommended appropriate actions to generally improve unreinforced masonry walls which include; incorporating lintels just above the opening carry on some of the loads from the top, reinforcement schemes like reinforcement bars so as to improve the load carrying capacity of the walls among others