Risk-Based Prioritization Approach to Construction Inspections for Transportation Projects

Abstract

Throughout the execution of highway construction projects, inspections are essential for maintaining project quality and ensuring greater traffic safety. Transportation agencies, however, have decreased the frequency of inspections due to current shortages of staffing and funding resources; consequently increasing safety risks and functional failures and reducing performance life. This study proposes a risk-based inspection (RBI) framework for optimizing construction inspections based on criticality. A total of 108 core inspection activities were retrieved from quality assurance (QA) documents. Risk impact (RI) data were collected from experts and a probabilistic risk assessment model was developed. In addition, a fuzzy set (FS) and Bayesian belief network (BBN) were amalgamated into a fuzzy Bayesian belief network (FBBN) for modeling. The FS pertained to the linguistics of the collected data, which could not be represented precisely by probability distribution. The causal relationship among the model variables was converted into a quantitative probability distribution and inferred using the BBN. A case study from the Kansas Department of Transportation was conducted to verify and test the framework. Results of FBBN adoption indicated that the modular representation of uncertain knowledge increases the efficiency and functionality of QA inspection risk analysis. Moreover, the unification of FS and BN quantitatively measured the RI and modeled the relationship between risk factors and RI. The framework output showed that more than half of earthwork and bridge deck inspections are high RI, while hot-mix asphalt (HMA) and portland cement concrete pavement (PCCP) require the most high-RI inspections. This study contributes to the construction engineering and management body of knowledge by providing an RBI framework for optimizing construction inspection activities in highways. The findings of this study also provide guidelines for highway agencies to develop RBI strategies.