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Three-dimensional concrete printing (3DCP) is emerging as an innovative technology and shows promise to revolutionize conventional construction modes. However, the current 3D-printed concrete (3DPC) generally requires higher cement content than conventional concrete to ensure its rheology for printing. From the perspective of cleaner production and reduce carbon emissions, this study explored the feasibility of replacing parts of cement with waste glass powder (WGP, 0%, 20%, 40%, and 60% by mass) and compared the properties of the developed 3DPC, including fluidity (flowable spread), rheology, heat of hydration, buildability, compressive strength, anisotropy, and drying shrinkage. The results showed that less than 40% WGP replacement had limited influence on the initial fluidity and static yield stress, as well as drying shrinkage, of 3DPC. Although the WGP inclusion decreased the compressive strength, it slowed down the fluidity loss and static yield stress increase, which could extend the workable time of the mixture for printing and improve buildability. The 40% WGP replacement was found increase to the buildability of the printing mixture from 150 mm to 155 mm. The printing mixture prepared with 60% WGP reduced the dying shrinkage by 50%. An exponential decay function between the fluidity and static yield stress was established so that the simple fluidity test could be used as an indicator of printability. The findings in this study provided a solution to reduce the consumption of cement in 3DPC, which could contribute to a greener production in the construction industry.

On 6 February 2023 at 09.17 BST, an earthquake measuring 7.8 on the Richter scale struck the southern border of Turkey near Syria, causing massive casualties and building damage. Badly damaged buildings need to be demolished, bringing a large amount of demolition waste, which, if not properly disposed of, can be a burden on the environment. In this study, damage to buildings in the quake-hit areas of Turkey is investigated, including reinforced structures and masonry structures. Based on this, the amount of demolition waste produced and the proportion of waste components are estimated roughly. Ultimately, the paper puts forward the strategy of recycling demolition waste after the earthquake and the application scenario planning of recycled products. Conclusively, the amount of demolition waste generated after the earthquake ranges from 450 to 920 million tons, providing new ideas for post-disaster reconstruction work. Besides, post-disaster waste management, safe demolition and environmentally friendly disposal and recycling technologies for demolition and construction wastes will bring good economic and environmental benefits, help the reconstruction of disaster areas, and provide a model for the resource utilization of construction and demolition waste worldwide.