Analysis of road construction waste generation in developing economies: A focus on surfacing and sub-base construction projects in Sri Lanka

The motivation for this study was to develop simplified tools to estimate material wastage during road construction projects. In developing countries, there is a lack of information about material wastage factors (MWFs) in road construction projects. The purpose of this study is to reveal the MWFs of materials used in road construction. To investigate MWFs, statistics were collected from a sample of 58 road contracts concluded in the southern province of Sri Lanka, comprising 245 road construction projects. Of the selected sample, 80% of the road projects utilized wearing course (asphalt concrete), aggregate base course (ABC), cationic slow setting emulsion 1 (CSS1) and sand. The mean MWFs were calculated only for ABC, wearing course and CSS1 as 8.69%, 5.21% and 6.8%, respectively, because the authors could only achieve acceptable precision levels for these three types of materials. The coefficient of variation (CV) for all these three types of materials ranged from 25% to 3%. Based on collected data, this study proposes equations to predict waste generation for CSS1 and wearing course. Implementing the derived equations to predict waste generation can aid in efficient planning and help construction companies to move towards more sustainable practices.