Strategic Mitigation Of Cost Overruns In Road Construction: An Integrated Ahp-Dematel Framework For Arsi Zone, Ehiopia

Abstract

Cost overruns are a chronic and pervasive challenge in the global construction industry, posing a significant threat to the successful delivery of critical infrastructure, particularly in developing nations like Ethiopia. Existing research often identifies numerous contributing factors but frequently fails to analyze their complex interrelationships, limiting the development of effective, context-specific mitigation strategies. This thesis aims to address this gap by developing and validating a data-driven strategic framework for mitigating cost overruns in road construction projects within the Arsi Zone. The study employs an integrated Analytic Hierarchy Process (AHP) and Decision-Making Trial and Evaluation Laboratory (DEMATEL) approach. Data was collected through structured surveys with a purposively selected panel of 12 experienced industry experts representing clients, contractors, and consultants. The analysis was conducted using MS Excel for data organization and Python programming for the core AHP and DEMATEL computations. The AHP results identified Ineffective Right-of-Way Management as the single most critical factor, with a global importance weight of 29.28%, highlighting its status as a systemic bottleneck. The DEMATEL analysis further uncovered the underlying causal architecture, distinguishing foundational drivers, such as Political Instability and Interference and Weak Capacity of Local Firms, from their highly visible but largely symptomatic effects, like Financial Difficulties of Contractor. The novelty of this study lies in the integrated analysis, which reveals a critical strategic paradox: foundational drivers perceived as having low importance by stakeholders are, in fact, the most influential root causes. This disconnect explains the industry's tendency toward reactive firefighting of symptoms rather than proactively addressing root causes. The final validated framework translates these findings into actionable recommendations for key beneficiaries, including the Ethiopian Roads Authority, contractors, and supervising consultants, providing a clear roadmap to shift from a reactive to a proactive, cause-driven management paradigm. The primary conclusion is that effective cost overrun mitigation requires prioritizing interventions that target these foundational drivers to achieve sustainable and long-term improvements in project cost performance.