INTERPRETIVE STRUCTURAL MODELING FOR INVESTIGATING FACTORS AND THEIR RELATIONSHIPS INFLUENCING ON-SITE SORTING OF CONSTRUCTION WASTE

Abstract

ABSTRACT On-site sorting of construction waste has been perceived as an effective measure for promoting sustainable construction. Previous studies have identified factors influencing the implementation of such construction waste sorting activities on-site. Most of them, however, focused on examining the factors from a single standpoint, disregarding the interrelationships between them. This paper seeks to investigate influential factors in implementing on-site construction waste sorting activities, with particular emphasis on their interactive relationships. Data was collected via semi-structured interviews with ten experienced professionals. The intricate interactive relationships among these factors were described and analyzed through the application of an Interpretive Structural Modeling approach and a Matriced’ Impacts Croises-Multipication Applique a Classement analysis. This yielded 13 principal factors that could be sorted into four categories: autonomous, dependent, linkage and driving—with six being considered as fundamental for successful on-site construction waste sorting; i.e., difficulty in sorting materials from mixed construction waste, limited space & environment at the site, low benefits from this activity, interference causing regular disruptions to site activities, immature recycled material market, and lack of government regulation support. In contrast to prior studies, the lack of manpower is no longer seen as being as critical an issue as before. Factors such as the difficulty in sorting materials from mixed construction waste, the limited benefit from on-site construction waste sorting, and the lack of government regulation support have become more critical. This study not only helps to identify the critical elements that affect on-site sorting of construction waste and their relationships, but also assists policymakers and practitioners in understanding the priority of measures needed to increase on-site sorting of construction waste.