AASHTO R 43-13 (2017) PDF Download

The AASHTO R 43-13 (2017) standard practice provides a method for quantifying the roughness of pavements. It involves calculating the International Roughness Index (IRI) statistic from longitudinal profiles measured with a road profiler in both the inside and outside wheelpaths of the pavement. The average of these two IRI statistics is then reported as the roughness of the pavement section.

The standard practice emphasizes the importance of having a quality assurance (QA) plan in place and provides guidelines for developing such a plan. It also clarifies that when there is a conflict between this standard practice and other references such as ASTM standards, this standard practice takes precedence for its intended purpose.

It is worth noting that this standard practice is a combination of two former provisional standard practices, namely PP 37 Standard Practice for Determination of International Roughness Index (IRI) to Quantify Roughness of Pavements and PP 37M Standard Practice for Quantifying Roughness of Pavements. This integration ensures a comprehensive and updated approach to quantifying pavement roughness.