The INDOT Long-Range Planning Section has developed a set of planning tools that will support the system-level analysis of the state transportation system. These tools are employed to monitor transportation system performance, identify highway needs, and provide a quantitative analysis of the impacts of transportation improvement projects. One such tool is HERS/IN (Indiana Highway Economic Requirements System). The HERS/IN model identifies deficiencies in pavement, capacity, and alignment by referring to the Highway Performance Monitoring System (HPMS) data of the roadway sections. The HERS model uses a method to accommodate the curve and grade data and, based on these data, it identifies highway alignment deficiencies. The roadway curve and grade data were collected in 1994 as a part of INDOT’s Pavement Management System. INDOT’s Long-Range Planning Section experienced difficulty in verifying these data and breaking it into meaningful segments. Therefore, the Indiana HPMS database did not include the curve and grade data. As a result, alignment deficiencies were not considered in the initial applications of HERS/IN. The objectives of the research project are to evaluate the curve and grade data available to INDOT and suggest a methodology that allows INDOT to identify alignment improvement projects, and to prioritize these projects. During the course of the project, we researched the various techniques used by other states to prepare the curve and grade database. We also learned about how other states program alignment correction projects. We evaluated the curve and grade data available to INDOT and how it can be used in HERS/IN to identify alignment correction projects. The research project provides INDOT with guidelines on how to efficiently program alignment correction projects.

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HERS, Highway Economic Requirements System, curve correction, alignment correction, curve data, grade data., SPR-2638

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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