Performance Evaluation and Treatment Selection of Micro Surfacing Projects in Louisiana

Abstract: The Louisiana Department of Transportation and Development (DOTD) currently utilizes an index-based decision matrix to select pavement maintenance and rehabilitation treatments, allowing for the prioritization of projects and effective allocation of funds. However, many of the index trigger values in the decision matrix were set over two decades ago based on limited pavement condition data. As a result, there is a need to reevaluate these triggers for more cost-efficient and timely pavement preservation. This study focused on reassessing the current decision trigger values for selecting micro surfacing treatments in Louisiana. The analysis included all micro-surfacing projects constructed since 2010, with relevant pavement design and performance data sourced from DOTD’s pavement management system (PMS) and other databases. The performance of these projects was evaluated through metrics such as pavement condition improvements, treatment effectiveness, and the extension of pavement life. Additionally, a project-level cost-benefit analysis was performed to determine the most appropriate timing for micro-surfacing applications under varying traffic and climate conditions across the state. Furthermore, a Markov chain modeling approach was applied to develop new pavement condition index models. This led to the creation of updated trigger values for pavement pre-condition indices, guiding the selection of micro surfacing treatments based on different pavement types (asphalt and composite) and highway classifications, with the goal of DOTD implementation.