| Description |
Thin Lift Treatments (TLTs) are a preservation method used during the early stage of the asphalt pavement life. They are a well-accepted method used by the pavement community to increase the lifespan of the pavement surface. TLTs can improve the smoothness of the pavement surface and provide a better driving experience when compared to untreated roads. The TLTs have been widely used under different environmental conditions. Three different types of TLT are used in Utah; however, their performance and durability have not been fully studied. Therefore, a standard evaluation of these three different types of TLTs is needed. The purpose of this study is to evaluate the performance of 14 different sections surfaced with TLTs under different traffic conditions and assess the service life of three different types of TLTs, then make recommendations about their lifespan. Two types of data were used in this work to evaluate the performance of the treatment: road surface condition and roughness. Road surface condition data were collected and digitized by an automated data collection vehicle, while roughness was evaluated by using an inertial system that records the ups and downs of the road and calculates the International Roughness Index (IRI) as part of UDOT Pavement Management System. Using these performance indicators, the road surface condition was evaluated based on the damage caused by environment and traffic. In total, 5 years worth of data for each road section were collected and used for the performance analysis. iv Evaluating the time-dependent data, the road surface performance as a function of time was found and the life of each type of TLTs was predicted. Based on the evidence and result, some key points are made to conclude this TLTs performance analysis. First, the weather is the main cause of distress in Utah; this is concluded by the fact that the estimated life based on the environment is shorter than the result from traffic. Second, high quality mixes like SMA do result in longer life by almost 40%. Third, road distresses do not correlate well with IRI; but roads in good condition have a higher chance of being smooth. Finally, the estimated life of TLTs in Utah is comparable to other studies. |
