Novel panel system for concrete masonry walls

Abstract

Masonry is one of the oldest materials that humans use for construction. It is durable, as seen on ancient structures built thousands of years ago, yet still in excellent shape. Recently, masonry walls have struggled to be competitive among other construction materials such as precast concrete, tilt-up walls, timber, etc. This is mainly due to construction practices and the lack of a standardized modular masonry system that prevents offsite construction. In this paper, new construction methods for concrete masonry walls are proposed. These methods are based on building partially grouted masonry panels that can be built onsite or offsite, then transported and assembled on the site. The methods commonly use a restrained unbonded post-tensioned (UPT) threaded bar to join panels. A full-scale experimental program campaign at the University of Alberta (UOA) is currently undergoing to test the proposed methods. Numerical models were developed before the experimental investigation to assess the behaviour of such techniques under out-of-plane loading. Bare joints, connecting panels reinforcement, and grouting joints are the three types of panel connections proposed here. The influences of the magnitude of prestressing and lateral restraints stiffness are also studied. The results show that the proposed approaches are comparable to traditionally constructed walls with improved serviceability. Also, because of the relative ease of construction and improved post-cracking behaviour, connecting panel reinforcement is the preferred method. Whereas the increasing level of prestressing enhances service conditions but leads to premature failure. Also, lateral restraints with high stiffness, such as grout or steel, are essential to enhance post-cracking behaviour.