Ingenieur Vol.82 April-June2020 | Page 22

INGENIEUR Figure 1: On-site Waste flow in most construction project sites from site management practices. The findings revealed that, there are no material flow cycles on selected project sites. Activities influencing waste generation on site Ten refurbishment activities were identified based on data from site observations, the combination of two-phase construction works (demolition and new construction) were generally involved among the selected projects and these became the main factors influencing the generation of refurbishment waste. These activities included hacking processes, knocking down the existing structure, fixing new floor tiles, fixing new wall tiles, painting, changing old fittings, constructing a new structure, constructing/changing/ installing fences/doors/windows, constructing/ changing the roof and finally unboxing the new construction materials/new fittings/household accessories etc. These ten activities were recognised as inevitable and most common onsite waste-producing activities. However, each refurbishment work activity generates different types of refurbishment waste material. The type of refurbishment waste that is occurring in each type of refurbishment work activity is shown in detail in Figure 2. Each refurbishment work activity generates different types of refurbishment waste material. From the survey, hacking and knockdown processes create a high volume of mixed waste made up off broken tiles, concrete, and bricks from the existing structure. Whereas, the fixing new floor tiles and the fixing new wall tiles, basically create a similar type of waste material such as broken tiles, extra new tiles due to the over orders, and broken tiles, which are caused during the cutting process. Additionally, all the extra paint and empty paint cans from painting become a waste. Changing the old fittings is believed to be one of the unavoidable works in any refurbishment that generates various types of large-scale waste, also known as bulky waste, such as kitchen cabinets, sinks, “kolah,” bathroom accessories, fan, baldock mesh, grills and many more. Furthermore, the survey indicated that the construction of new structure during refurbishment, such as beams and slabs built by adopting the conventional method of construction using timber or plywood for precast formwork creates wood waste. Therefore, wood waste is largely generated besides 20 VOL 82 APRIL-JUNE 2020