Comprehensive Testing Guidelines to Increase Efficiency in Indot Operations

The Joint Transportation Research Program serves as a vehicle for INDOT collaboration with higher education institutions and industry in Indiana to facilitate innovation that results in continuous improvement in the planning, design, construction, operation, management and economic efficiency of the Indiana transportation infrastructure. NOTICE The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views and policies of the Indiana Department of Transportation or the Federal Highway Administration. The report does not constitute a standard, specification or regulation. When INDOT designs a pavement project, the decision for QC/QA or non‐QC/QA is made solely based on the quantity of pavement materials. However, the actual risk will vary depending on the severity of road conditions. The question is how to differentiate the quality testing efforts according to the severity of road conditions in order to balance required testing resources. We found that the number of commercial vehicles (CV) and heat index (HI: number of hot days/freezing index) can be used as criteria in classifying the road conditions. Using these two criteria, CV and HI, we classify the road sections into four classes and provide different testing guidelines for different classes. 17. When the Indiana Department of Transportation designs a pavement project, a decision for QC/QA (Quality Control/Quality Assurance) or non–QC/QA is made solely based on the quantity of pavement materials to be used in the project. Once the pavement project is designated as QC/QA, quality characteristic values through a certain testing requirement (test types and sample sizes) are obtained and evaluated in comparison with certain testing criteria to ensure that the constructed pavement will meet the pavement design life. In the current INDOT practice of pavement materials testing, a testing requirement (QC/QA or non–QC/QA) is uniformly applied based on pavement quantity, regardless of road condition factors, such as traffic load, climate, and speed limit, that largely affect the pavement lifetime realistically. However, the actual risk will vary depending on the severity of road conditions; severe climate and heavily loaded traffic cause certain roads to fail much earlier than their designated design life, while other roads last much longer. There is an opportunity here to balance required testing resources by differentiating testing requirements for different road conditions. Stricter testing requirements for roads under severe conditions will reduce the error of …