Integration of lean management and sustainability at construction supply chain management level as a competitive advantage tool

Abstract

Success and performance of construction companies' supply chains can influence competitiveness, cost and time effectiveness, sustainability and lean performance of construction companies. Suppliers' selection decision and supply chain establishment at the very beginning of the project can play important role in minimization of potential problems. Moreover, lean and sustainable supply chain can be affected and supported by cooperation with the most suitable suppliers. This thesis aims to determine the effective criteria in supplier selection to establish sustainable construction supply chain and to propose a conceptual model which can be considered to be used in supplier selection to establish sustainable construction supply chain. So that, the focus of this thesis is on the supply chains initial establishment phase. With this aim, following the literature review and examining 16 standards, indices and certificates, the Delphi Method and Best-Worst Method (BWM) were applied and interviews were conducted. Examination of the 16 standards, indices and certificates revealed 649 criteria which have been refined through elimination of the overlapped criteria. In total 222 criteria were remained and grouped under 4 categories. Based on these 4 categories of criteria, four groups (i.e., PHO, EMD, PR, and SC) of four round Delphi surveys were performed. As a result of the Delphi surveys, 11 criteria in the PHO group, 8 criteria in the EMD group, 8 criteria in the PR, and 7 criteria in the supply chain groups were selected. Delphi surveys' outputs provided input to the BWM. The criteria to be used in supplier selection were searched by calculating the optimal and global weights obtained from the experts. As a result of BWM, in the group rankings, SC group was indicated to have the greatest impact whereas the PHO group was indicated to have the least impact. Furthermore, according to the BWM, the top ten global weighted criteria in the descending order are: SC6, SC7, SC2, SC1, SC5, SC4, EMD7, EMD6, EMD2, and EMD4. These criteria list, which can be considered as potential input to the suppliers' selection phase in lean and sustainable construction supply chain management, has been proposed within the conceptual model. Interviews were held with experts on the research findings. All interviewees agreed that the criteria and conceptual model can be applicable to the construction industry and can facilitate supply chain management in the construction industry. Considering these 10 criteria and using them as potential inputs to supplier selection can support the construction industry professionals' decision-making process in lean and sustainable construction supply chain management.