New research highlights a practical question many in construction are asking: Can masonry units made with industrial by-products hold up in real exposure conditions, not just in short-term lab tests?
In a published study, researchers evaluated composite interlocking bricks produced with a mix that included fly ash, manufactured sand, lime, gypsum, crushed rubber, and granite waste powder used as partial substitutes for traditional ingredients. The team formed two brick sizes using hydraulic compression molding, then measured compressive strength and tracked chemical durability over time.
To simulate aggressive environments that matter on jobsites, the bricks were exposed for up to 120 days to 5% sodium chloride, 5% sodium sulfate, and natural seawater. The study also used scanning electron microscopy and energy-dispersive X-ray spectroscopy to evaluate the prepared powder mixture and help explain performance changes.
One takeaway was that granite waste powder content mattered. Mixes with about 20% to 30% granite waste powder showed improved resistance to sulfate and chloride intrusion, and the blend with 30% granite waste powder delivered the best compressive strength in this study.
For mason contractors, the bigger point is that “sustainable” units still have to perform under salts and moisture that drive durability problems. If an owner, architect, or supplier proposes alternative brick products that include recycled or waste materials, ask for durability testing that matches the project’s exposure, including chloride and sulfate conditions when relevant. Also confirm compressive strength results, quality control consistency, and how the unit is intended to be installed, especially when the product is described as interlocking.
Read the full, original article from Springer Nature Link here.