Causal relationships among social sustainability indicators for freeways

Purpose Social sustainability is a contextual and multifaceted dimension comprising interconnected systems and associated indicators. Prior research has concentrated on investigating the various social sustainability indicators, but their interrelationships and the uncertainty issues arising from human evaluation have been disregarded. This study aims to analyse causal interrelationships among the indicators that affect the life cycle social sustainability performance of freeways. Design/methodology/approach This study conducted 16 semi-structured interview surveys with experts involved in designing and constructing freeway projects around Australia. The complex interrelationships were analysed using the fuzzy decision-making trial and evaluation laboratory method. This method addresses the ambiguity inherent in human judgments and quantifies various social indicators based on their intricate relationships. Findings A framework is developed to categorise 42 indicators into cause-and-effect groups and rank them according to their significance and interactions with other indicators. According to the results obtained, the top five significant indicators are “ensure a sense of belonging and authorisation for local communities”, “stakeholder influence in the project”, “freedom of expression for the local communities”, “maintain the personal dignity of the project workforce” and “identification and involvement of the project stakeholders”. Practical implications The proposed framework would assist the project management teams and consultants in prioritising indicators based on their complex interrelationships and planning strategies for enhanced life cycle social sustainability of freeways in the future. Originality/value This research offers a comprehensive understanding of various indicators affecting the social sustainability performance of freeways exclusively by efficiently addressing the participating experts’ subjective judgements and vagueness.