This student study project investigates the feasibility of using thick granular base for flexible pavement design in Ohio. The criteria considered include the performance criteria and life cycle economic analyses. The performance of different types of base layer design are compared using the LTTP database. The focus is on the ability of achieving uniform dynamic deflections using Falling Weight Deflectometer (FWD) data. Based on FWD record from LTTP database, the relative merits of different base type design are compared. The pavement performance is predicted using MEPDG design software. A sensitivity study is conducted on the effects of granular base layer parameters on the pavement performance. From the relative improvement in terms of pavement distress reduction, an optimal base layer thickness of 12 in to 15 inch is identified. The use of thicker granular base (from the current 4 in to 6 in granular base currently used in Ohio to 12 inch thick granular base) is predicted to increase the pavement service life for around 30% using the criteria for common types of distresses. A life cycle analyses are conducted using a simplified model. The model indicates that for the typical Ohio flexible pavement sections, doubling the thickness of base layer, while causes higher initial construction cost, will result in life cycle cost savings. Thus performance prediction using MEPDG and life cycle economic analyses both support positively the use of granular base in flexible pavement design in Ohio. It is also found in this study that the climate model of the existing MEPDG design software does not adequately account for the regional climate conditions (such as freeze-thawing effects) on pavement performance. It is recommended to conduct further analyses of field performance data to validate the MEPDG model predictions. Finally, recommendations are provided on the specifications for screening the supplying sources of granular materials for granular base construction.

The purpose of this manual is to provide clear and helpful information for maintaining gravel roads. Very little technical help is available to small agencies that are responsible for managing these roads. Gravel road maintenance has traditionally been "more of an art than a science" and very few formal standards exist. This manual contains guidelines to help answer the questions that arise concerning gravel road maintenance such as: What is enough surface crown? What is too much? What causes corrugation? The information is as nontechnical as possible without sacrificing clear guidelines and instructions on how to do the job right.

This report contains guidelines and recommendations for managing and designing for friction on highway pavements. The contents of this report will be of interest to highway materials, construction, pavement management, safety, design, and research engineers, as well as others concerned with the friction and related surface characteristics of highway pavements.

Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.

"TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 445: Practices for Unbound Aggregate Pavement Layers consolidates information on the state-of-the-art and state-of-the-practice of designing and constructing unbound aggregate pavement layers. The report summarizes effective practices related to material selection, design, and construction of unbound aggregate layers to potentially improve pavement performance and longevity."--Publisher website.

A comprehensive, state-of-the-art guide to pavement design and materials With innovations ranging from the advent of SuperpaveTM, the data generated by the Long Term Pavement Performance (LTPP) project, to the recent release of the Mechanistic-Empirical pavement design guide developed under NCHRP Study 1-37A, the field of pavement engineering is experiencing significant development. Pavement Design and Materials is a practical reference for both students and practicing engineers that explores all the aspects of pavement engineering, including materials, analysis, design, evaluation, and economic analysis. Historically, numerous techniques have been applied by a multitude of jurisdictions dealing with roadway pavements. This book focuses on the best-established, currently applicable techniques available. Pavement Design and Materials offers complete coverage of: The characterization of traffic input The characterization of pavement bases/subgrades and aggregates Asphalt binder and asphalt concrete characterization Portland cement and concrete characterization Analysis of flexible and rigid pavements Pavement evaluation Environmental effects on pavements The design of flexible and rigid pavements Pavement rehabilitation Economic analysis of alternative pavement designs The coverage is accompanied by suggestions for software for implementing various analytical techniques described in these chapters. These tools are easily accessible through the book’s companion Web site, which is constantly updated to ensure that the reader finds the most up-to-date software available.