Verification of rut depth collected with the INO Laser Rut Measurement System (LRMS)

Pavement rutting can be an indicator that a section of roadway is in need of repair or replacement. It can also become a hazard to drivers, causing loss of control or hydroplaning when water accumulates. To better monitor pavement conditions throughout the state, the Ohio Department of Transportation (ODOT) purchased two road profilers with INO Laser Rut Measurement Systems (LRMS). The vehicle mounted systems provide ODOT pavement condition raters with a faster and safer method for evaluating pavement conditions. This study was intended to evaluate the accuracy, precision, and repeatability of the LRMS system and determine the correlation between manually collected data and data collected using the LRMS. The system's performance was evaluated by collecting rut measurements over two sections of pavement using the LRMS, the straight edge method, and a mechanical profiling system developed by the Ohio Research Institute for Transportation and the Environment (ORITE) and comparing results. The study showed that the LRMS produces accurate and repeatable results that are similar to those produced with a straight edge or profilometer. Minor adjustments to the Pavement Condition Rating (PCR) system are needed, however, to ensure that scores properly represent the condition of the pavement. A range of 5-25% is recommended for the "occasional" extent classification when the LRMS is used.