A fuzzy evaluation and selection of construction and demolition waste utilization modes in Xi'an, China

The inadequate reuse and recycle of construction and demolition waste (C&DW) has been identified as a major issue, as it implies the depletion of natural aggregates, massive occupation of landfill and inefficiency of construction industry. However, a holistic view involving economic, technical and comprehensive dimensions has rarely been adopted for C&DW utilization evaluation against both qualitative and quantitative criteria. In this study, we propose a framework in a heterogeneous group decision-making environment to solve the C&DW utilization mode selection problem by integrating the Choquet integral and the elimination and choice translating reality (ELECTRE) method with two data forms, that is, interval-valued hesitant fuzzy numbers and real numbers. Firstly, an evaluation index system is constructed to assess multiple representative C&DW utilization modes in Xi'an, China. Secondly, a novel method is proposed to apply the Choquet integral for aggregation of evaluation values and fuzzy ELECTRE for outranking of C&DW utilization modes after the heterogenous evaluation data are unified into interval numbers. Thirdly, to illustrate the application of the proposed framework, this paper evaluates four typical C&DW utilization modes based on a case study in Xi'an, China, and the result shows that the most preferable mode is A₃ (off-site crushing, roadbed backfilling). Finally, a comparative analysis is conducted to verify the effectiveness of this framework. This study presents useful findings to C&DW practitioners and can help avoid intuitive selection among available C&DW utilization modes.