Focus


Book Description




Performance Evaluation of Rubblized Pavements in Iowa


Book Description

This Phase II follow-up study of IHRB Project TR-473 focused on the performance evaluation of rubblized pavements in Iowa. The primary objective of this study was to evaluate the structural condition of existing rubblized concrete pavements across Iowa through Falling Weight Deflectometer (FWD) tests, Dynamic Cone Penetrometer (DCP) tests, visual pavement distress surveys, etc. Through backcalculation of FWD deflection data using the ISU's advanced layer moduli backcalculation program, the rubblized layer moduli were determined for various projects and compared with each other for correlating with the long-term pavement performance. The AASHTO structural layer coefficient for rubblized layer was also calculated using the rubblized layer moduli. To validate the mechanistic-empirical (M-E) hot mix asphalt (HMA) overlay thickness design procedure developed during the Phase I study, the actual HMA overlay thickness from the rubblization projects were compared with the predicted thickness obtained from the design software. The results of this study show that rubblization is a valid option to use in Iowa in the rehabilitation of PCC provided the foundation is strong enough to support construction operations during the rubblization process. The M-E structural design methodology developed during Phase I can estimate the HMA overlay thickness reasonably well to achieve long-lasting performance of HMA pavements. The rehabilitation strategy is recommended for continued use in Iowa under those conditions conducive for rubblization.




Improved Mix Design, Evaluation, and Materials Management Practices for Hot Mix Asphalt with High Reclaimed Asphalt Pavement Content


Book Description

TRB's National Cooperative Highway Research Program (NCHRP) Report 752: Improved Mix Design, Evaluation, and Materials Management Practices for Hot Mix Asphalt with High Reclaimed Asphalt Pavement Content describes proposed revisions to the American Association of State Highway and Transportation Officials (AASHTO) R 35, Superpave Volumetric Design for Hot Mix Asphalt, and AASHTO M 323, Superpave Volumetric Mix Design, to accommodate the design of asphalt mixtures with high reclaimed asphalt pavement contents.




Progress Report


Book Description




Advances in Materials and Pavement Performance Prediction II


Book Description

Inspired from the legacy of the previous four 3DFEM conferences held in Delft and Athens as well as the successful 2018 AM3P conference held in Doha, the 2020 AM3P conference continues the pavement mechanics theme including pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance. The AM3P conference is organized by the Standing International Advisory Committee (SIAC), at the time of this publication chaired by Professors Tom Scarpas, Eyad Masad, and Amit Bhasin. Advances in Materials and Pavement Performance Prediction II includes over 111 papers presented at the 2020 AM3P Conference. The technical topics covered include: - rigid pavements - pavement geotechnics - statistical and data tools in pavement engineering - pavement structures - asphalt mixtures - asphalt binders The book will be invaluable to academics and engineers involved or interested in pavement engineering, pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance.










Consideration of Preservation in Pavement Design and Analysis Procedures


Book Description

"TRB's National Cooperative Highway Research Program (NCHRP) Report 810: Consideration of Preservation in Pavement Design and Analysis Procedures explores the effects of preservation on pavement performance and service life and describes three different approaches for considering these effects in pavement design and analysis procedures. The report may serve as a basis for developing procedures for incorporating preservation in the American Association of State Highway and Transportation Officials (AASHTO) Mechanistic-Empirical Pavement Design Guide: A Manual of Practice (MEPDG) and the AASHTOWare Pavement ME Design software. Initially, the scope of this project intended to develop procedures for incorporating pavement preservation treatments into the MEPDG design analysis process that would become part of the MEPDG Manual of Practice. However, it was determined that sufficient data were not available to support the development of such procedures. Appendices A through I are available online only." --




LTPP Traffic Data Collection and Monitoring


Book Description

This report presents a summary of vehicle count, classification, and weight data collection and monitoring effort at the initial 27 program sites around the state of Arizona, most of which were installed in October/November 1992. It highlights procedures taken to identify performance shifts, calibration of equipment, and on-going efforts to upgrade and expand the data collection program.




Impact of Design Features on Pavement Response and Performance in Rehabilitated Flexible and Rigid Pavements


Book Description

The primary focus of this research was to determine the effects of design and construction features, such as overlay thickness and mix type, presence of milling, and type of restoration, on pavement response and performance and to establish their importance in the prediction of future performances of rehabilitated pavements. Long-Term Pavement Performance program Specific Pavement Study (SPS)-5 and SPS-6 experiments provided information to obtain a better understanding of the effects of design and construction features on pavement response and performance of rehabilitated flexible and rigid pavements.