In the heart of Shanghai, researchers at Tongji University are turning trash into treasure, quite literally. Jiao-Long Zhang, a lead author affiliated with the College of Civil Engineering at Tongji University and the State Key Laboratory of Disaster Reduction in Civil Engineering, has been spearheading a study that could revolutionize the construction industry. The research, published in the journal *Cleaner Materials* (translated as “Cleaner Materials” in English), explores the potential of municipal solid waste incineration (MSWI) bottom ash as a sustainable additive in 3D-printable mortar.
The study, titled “3D-printable mortars incorporating municipal solid waste incineration bottom ash: Linking hydration to extrudability and mechanical performance,” delves into the impact of MSWI bottom ash on the rheological behavior, mechanical strength, and hydration of printable mortar. The findings are nothing short of groundbreaking. By replacing cement with MSWI bottom ash in varying proportions, the research team discovered significant improvements in the material’s performance.
“Incorporating 20% MSWI bottom ash enhances rheological performance and reduces the anisotropy coefficient,” Zhang explained. This enhancement is attributed to the physical filler effect of fine ash particles and the pozzolanic reaction, which contribute to particle cohesion and the formation of calcium silicate hydrate (C-S-H). The structuration rates observed were 11, 8.8, 12.3, and 7.5 kPa/min for the control mix (M-0) and the mixes with 10% (M-10), 20% (M-20), and 30% (M-30) MSWI bottom ash, respectively. Notably, M-20 achieved a 4% increase over the reference mix, resulting in an absolute increase of 8 layers and a 57% relative improvement in buildability.
The initial yield stress of M-20 was 0.55 kPa, classified as moderately stiff for extrusion and layer support. At 28 days, the anisotropy coefficient for flexural strength decreased from 0.159 in M-0 to 0.110 in M-20. These findings suggest that 20% MSWI bottom ash is the optimal replacement level for 3D printable mortar.
The commercial implications for the energy sector are substantial. As the world grapples with the challenges of waste management and sustainable construction, this research offers a promising solution. By utilizing MSWI bottom ash, construction companies can reduce their reliance on cement, a major contributor to carbon emissions. This not only promotes sustainable construction but also opens up new avenues for waste management.
The study’s findings could shape future developments in the field of 3D-printed construction materials. As Zhang and his team continue to explore the potential of MSWI bottom ash, the construction industry stands on the brink of a sustainable revolution. The integration of waste materials into construction processes could redefine the way we build, paving the way for a greener, more efficient future.
In the words of Zhang, “This research is just the beginning. The possibilities are endless, and we are excited to see how our findings will impact the industry.” As the world moves towards a more sustainable future, the work of Zhang and his team at Tongji University serves as a beacon of hope and innovation.