Potential Use of Longer Combination Vehicles in Texas: Second-Year Report

摘要

The second year of this study focused on Texas highway corridors carrying heavy truck volumes and examined LCV operations--particularly infrastructure costs--to identify where the highest economic advantage from LCV implementation would be achieved. First an Executive Summary of the entire study describes the two-year findings. Then Chapter 1 provides a short background and summarizes the outlines of both reports. Chapter 2 covers the potential LCV impacts on the pavements of the high volume heavy truck corridors (segments) on the TxDOT system. The work is a fundamental contribution to estimating pavement life and critical in ensuring that any recommended increase of truck size or weight meets the marginal cost rule. The chapter covers the method used to determine pavement life, together with the collection and analysis of data required in the evaluation. It reports the characteristics, analysis, results, and conclusions for each of five Texas corridors. The chapter then summarizes the findings for both rigid and flexible pavement and closes with limitations and recommendations for additional research. Chapter 3 identifies LCV impacts on the bridges identified on the corridors specified in Chapter 2. It describes the method selected to determine bridge impacts, including the traditional moment analysis method and a fatigue moment analysis method that promises greater precision. The LCV types selected for study analysis--97,000 lb tridem, 138,000 lb double 53 feet, and a 90,000 lb double 53 feet--are then introduced sequentially and the results for both moment methods given. Results are then summarized with one surprising result. Chapter 4 provides the findings regarding users, pavements, and bridges.