The fourth industrial revolution transforms the built environment through several highly intelligence systems such as drones, 3D printers, robotics, as well as building information modelling (BIM) and geographic information systems (GIS). This transformation has widely been applied in buildings. However, to establish environmental sustainability in the built environment, this transformation needs to be expanded in other sectors that impact climate change such as construction and demolition waste materials. The aim of this chapter is to introduce a new conceptual model that can measure construction and demolition waste in real time and optimise their carbon footprint spatially. A quantitative methodology that embraces a measuring protocol and geospatial research method is proposed for this purpose. The proposed model is capable of measuring the recycling potential result in construction sites to support the circular economy as well as to mitigate the associated carbon dioxide emissions (CO2) with materials' embodied energy, transportation, and treatment.
Top1. Introduction: Problem Statement And Environment
Construction and demolition waste materials (CDW) belong to the solid waste stream (You et al., 2020). The construction and demolition waste stream consists of inert and non-inert materials that result in several residential, renovation, infrastructure as well as demolition projects (Lam et al., 2019). The most commonly used inert CDW materials are asphalt, bricks, concrete, drywall and excavation products such as soil, rocks and gravel (Lam et al., 2019; Wu et al., 2019). Wooden products such as timber and packaging waste materials as well as metals are considered to be the most often used non-inert CDW materials in construction projects (Wu et al., 2019).
The inefficient management of the construction and demolition waste materials is globally responsible for serious harm environmentally, socially and economically (X. P. Wang et al., 2019; Wu et al., 2020; Zhang et al., 2019). Environmental impact is perhaps the most visible and measurable. Critically, it is often proposed that the CDW stream has an impact on climate change. Particularly, CDW materials may contribute to global warming in two key ways; through the released carbon dioxide emissions (CO2) that are associated with industrial production processes and embodied carbon as well as during their transportation and treatment phase (Giesekam, 2016; Huang et al., 2018; Wu et al., 2020).
Discarding CDW materials unlawfully or in unauthorised sites may induce significant land and water pollution as the non-inert materials contain asbestos, mercury or other toxic substances (Santos et al., 2019; Tam & Lu, 2016; Yu et al., 2018). Neglected construction waste stockpiles consisting of timber, carpets, roofing and other flammable building materials may cause fires harming both the ecosystem and human lives (NSW Government, 2020). Therefore, the approaches regarding discarding waste materials are important and the need to develop better strategies is evident to effectively manage such a global problem.
Despite the magnitude of the problem, CDW materials are still disposed of in landfills with so little thought, limiting their space due to their bulky size (Jain et al., 2019; Srour et al., 2019). This limitation forces authorities to seek for new disposal areas limiting further the open and green spaces, thus, delivering a less sustainable built environment in the future generations. Even worse, the mindless disposal of CDW materials can cost people’s lives due to a landslide of a landfill. It is worth noting that 73 and 30 people died in 2015 and 2017 in China and Sri Lanka respectively due to the fatal landslides of the unlawfully discarded CDW materials (Duan et al., 2019, p. 1).