Xu, X., Zhang, Y., Yuan, C., Cai, H., Abraham, D. M., & Bowman, M. D. (2019). Risk-based construction inspection (Joint Transportation Research Program Publication No. FHWA/IN/JTRP-2019/06). West Lafayette, IN: Purdue University. https://doi.org/10.5703/1288284316916
Construction inspection is a critical component in the quality assurance (QA) program to ensure the quality and long-term performance of pavements. Over the years, INDOT has been developing and modifying its standard specification to set requirements for construction inspection and material testing. With the retirement of experienced employees, INDOT is challenged with the lack of knowledge to effectively inspect the critical elements of construction results/deliverables such as pavement, soil embankment, and bridge (decks). There is a critical need for INDOT to allocate limited resources to the riskiest areas and equip construction inspectors with necessary knowledge to conduct inspection, ensure the quality of construction results, and minimize risks to INDOT.
This study developed a risk-based inspection guide that has addressed the aforementioned problems of shortage in staffing and loss and lack of knowledge by providing answers in aspects of what, when, how, and how often to inspect. A comprehensive list of testing and inspection activities were extracted from INDOT’s material testing manual, INDOT’s standard specification, and the QA implementation at the Ohio River Bridge (ORB) project. This list was narrowed down to a core set of items based on survey responses and interviews with INDOT domain experts. Testing and inspection activities in the core set were aligned with the construction process. The risk associated with each inspection activity was assessed by considering both the probability of failure and consequence severity of failure in four dimensions: cost, time, quality, and safety. A composite risk index was developed as a single measure for the overall risk. All inspection activities were prioritized based on the composite index. For implementation, a linking mechanism was developed to link inspection activity, pay item, and check items (extracted from specification). This linking mechanism aligns with the business process of construction inspection at INDOT: starting with a pay item, field inspectors retrieve the associated check items and their inspection priority (based on risk), inspection frequency, and inspection criteria. A digital, ontology- and risk-based inspection system was proposed and its conceptual model was delivered to INDOT for its incorporation in the field application of construction documentation, a component of the e-Construction initiatives at INDOT. It will be tested on Project R-30397 through a pilot study.
quality assurance, QA/QC, construction inspection, risk assessment, knowledge management, ontology, digital inspection system, risk-based inspection
Joint Transportation Research Program
Indiana Department of Transportation
West Lafayette, Indiana
Date of this Version