Comparing the Mechanical and Environmental Performance of Old and New Canadian Bricks for Reuse in Building Alterations

Climate change has been increasing at an alarming rate during the last few decades. According to recent studies, Canada's average temperature over land has risen by 1.7 °C in the last 50 years. Reusing materials from old masonry building can reduce the waste and help mitigate the effect of climate changes in Eastern Canada. Construction, renovation, and demolition (CRD) is considered Canada’s largest waste stream with over 80% of solid wastes. This paper presents a preliminary study that quantifies both the mechanical and environmental properties for several types of old and new local clay bricks. Old bricks were retrieved from deconstructed buildings in Montreal (Quebec) that are dated to the nineteenth century. The new bricks used in this study are instead the most common types used in Canada’s construction nowadays. Several batches of old and new bricks underwent the same procedures of testing to ensure fair comparisons among all the samples. The mechanical characterization included destructive and non-destructive testing to assess the compressive and flexural strength of each brick. Tests performed comprised uniaxial compression, ultrasonic pulse velocity (UPV), and three point bending on both bricks and smaller prisms to investigate size effects. On the other hand, the environmental characterization included two pass/fail tests that are presently adopted by the Canadian Standard Association’s CSA-A82 to assess freeze and thaw resistance, namely 50 cycle-long freeze–thaw tests and a much faster 24-h absorption test followed by a 5-h boiling to obtain the water absorption ratio. Results are presented and compared for different samples and considerations are made for reusing such masonry products in building alterations, alongside some key limitations that our tests highlighted.