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AbstractThe construction sector in Bangladesh is facing negative impacts on financial and environmental aspects due to excessive waste generation. The construction industry cannot function properly if its resources are being wasted abruptly. Therefore, this study aims to identify the construction waste-generating factors and develop construction waste management strategies for the construction industry of Bangladesh. This research was conducted through an extensive survey which was done by interviewing various construction professionals and reviewing existing literature rigorously. The survey was conducted on the basis of the Likert scale, and the waste-generating factors were prioritized using the Relative Importance Index (R.I.I). The factor identification revealed that ‘deposited material in a public place’ is the most significant waste generating factor on construction sites. In addition, improper material storage, lack of training of workers, solid waste, and the absence of proper guidelines for workers are also identified as the top reasons for construction waste. Furthermore, stakeholders’ opinions on construction waste minimization have revealed a huge opportunity to manage those potential waste generation factors in a project. This investigation would be able to picture out the whole waste generation scenario and suggest important waste management strategies in the context of the Bangladeshi construction sector.

ABSTRACTThis study investigates the performance of recycled aggregate concrete incorporating different sizes and concentrations of coarse aggregate under sodium sulphate and normal water curing. Ten mixes were produced, having two control mixes of 12 to 20 mm and 5 to 12 mm coarse aggregate size. The rest of the mixes have supplementary cementitious material with 0%, 15%, 30%, and 45% substitution of respective sizes normal aggregate by recycled aggregate. The fresh recycled aggregate concrete mixes were assessed through the slump, ball penetration, and compacting factor test, which exhibited a falling trend with the percentage increase of recycled aggregate. Moreover, compressive strength and ultrasonic pulse velocity drop with the percentage of RCA increases at 7, 28, and 91-days normal curing and 5% Na2SO4solution curing at 91 days. The compressive strength and ultrasonic pulse velocity of 5-12 mm coarse aggregate concrete showed improvement over 12–20 mm coarse aggregate concrete of the same replacement for both curing. However, 5% Na2SO4solution curing specimens exhibit around 5–11% decrease in compressive strength and higher penetration depth than normal curing . Furthermore, the outer face of the silica fume included samples have received fewer white patches after sodium sulphate immersion.