Recently published ICT research reports online

The following reports from recently completed Illinois Department of Transportation-sponsored projects are now available on ICT’s website.

R27-124: Evaluation of Aggregate Subgrade Materials Used as Pavement Subgrade/Granular Subbase. With recent focus on sustainable construction practices and the ever-increasing transportation costs and scarcity of natural resources, integration of large-size and marginally acceptable aggregates and recycled materials (e.g., reclaimed asphalt pavement) with current construction specifications is becoming imperative. To this end, a research study was undertaken by ICT researchers to evaluate the adequacy and field performances of IDOT’s new aggregate subgrade specifications.

R27-125: Sustainable Aggregates Production: Green Applications for Aggregate By-Products.  In this Phase 1 study, ICT researchers investigated methods for using aggregate by-products, which are currently being wasted, to lower overall costs to IDOT and extend the use of natural aggregate resources. This report addresses quarry production techniques and properties of selected samples of quarry fines and contains recommendations about potential sustainable uses of fines, which will be investigated in Field Performance Evaluations of Sustainable Aggregate By-product Applications, Phase II (R27-168).

R27-130: Development of Improved Overlay Thickness Design Alternatives for Local Roads.  A new mechanistic-empirical (ME) overlay design method was developed to adequately assess the structural conditions of existing pavements and subsequently recommend required thickness values. The ME overlay design method successfully identified structural deficiencies in the original pavement configurations through nondestructive testing and subsequently resulted in reliable and cost-effective overlay solutions.

R27-135: Enhancements to Highway Construction Scheduling Expert System. The primary objective of this research was to enhance the software tool, Illinois Construction Scheduling Expert System (ICSES). Project data on more than 4,200 recent IDOT statewide projects were collected and analyzed to determine historical production rates, controlling items, and the typical order of activities. The resulting information was incorporated into ICSES to enhance the accuracy and functionality of the construction scheduling tool.