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Data availability: data will be made available on request. Copyright © The Authors 2023. The built environment sector is under increasing pressure to reduce costs while improving environmental quality. This paper examines Kuwait’s current construction and demolition waste (CDW) management policy, highlights the obstacles faced by recycling processes and suggests solutions to enhance waste management practices. Kuwait has only one landfill dedicated exclusively to CDW, operating since 2009. Even though Kuwait has facilities dedicated to handling and recycling CDW, recycling faces several obstacles that hinder its efficacy. This study aims to identify the impediments to efficient management practices through an extensive review of the literature followed by a questionnaire that was sent to 42 relevant stakeholders and interviews conducted with five stakeholders from the 1) Municipality of Kuwait, 2) the Ministry of Public Works, 3) the Environmental Public Authority, 4) the Kuwait Institute for Scientific Research, and 5) the Environment Preservation Industrial Company. This study concluded that present waste management procedures are inappropriate for achieving the circular construction concept and the 4 R framework (reduce, reuse, recycle and recover). Furthermore, it was found that raising the awareness of construction stakeholders and the public about waste management and recycling benefits is essential. This can be successfully implemented by emphasising recyclable products' economic and financial benefits. There is also a need to enforce Kuwait’s existing environmental legislation and regulations to achieve a better CDW control framework. The outcomes of this study will assist decision-makers in establishing strategies to address the barriers to circular waste management practices in Kuwait and beyond.

The weak mechanical properties the 3D printed parts can limit the competence of this technology when compared to conventionally cast-in-mold cementitious composites structures. However, experimental results in this study showed that the incorporation of nano additives could improve the mechanical property of printed structures. Six geopolymeric mixtures were designed and tested for their flow-ability, shape stability, buildability and mechanical performance. Different dosage of nano graphite platelets (NGPs) ranging from 0.1% to 1%, by the weight of geopolymer, were incorporated to the best performing geopolymer. The 3D printed geopolymer with 1% of NGPs increased the flexural strength by 89% and 46% compared to the same 3D printed and casted geopolymer without any NGPs, respectively. The same increase for compressive strength was 28% and 12%. Moreover, the geopolymer mix containing 1% of NGPs demonstrated the best shape retention and buildability.

Hot metal gas forming (HMGF) is a desirable way for the automotive industry to produce complex metallic parts with poor formability, such as aluminum alloys. A simple hot gas forming method was developed to form aluminum alloy tubes using flame heating. An aluminum alloy tube was heated by a flame torch while the tube was rotated and compressed using a lathe machine and simultaneously pressurized with a constant air pressure. The effects of the internal pressure and axial feeding on expansion and wall thickness distribution were examined. The results showed that the proposed gas forming method was effective for forming aluminum alloy tubes. It was also indicated that axial feeding is a vital parameter to prevent reductions in wall thickness by supplying the material flow during the forming process.

Graphite nano-platelets (GNPs) and graphene oxide (GO) modify cementitious materials from the nano- to the macroscale, resulting in enhanced mechanical properties, durability and, eventually, physical multi-functionality. A systematic study on EN 998-2 premixed mortars modified with GNPs or GO is reported. Rheological properties of fresh mortars were investigated in terms of shear stress (or apparent viscosity) versus shear rate. Mortars were casted in bars and hardened for 28 or 14 days. Density, microstructure, compressive and flexural strength of hardened samples were evaluated and compared.