This synthesis will be of interest to state DOT construction, materials, statistical, specification, and inspection engineers; DOT research staff; pavement construction material suppliers; highway construction contractors; and civil engineering consulting firms, including field and laboratory materials testing personnel. The synthesis describes the state of the practice for defining and measuring variability in highway pavement construction. Data obtained from a review of the literature, a survey of state departments of transportation (DOTs), and discussions with selected state DOT personnel and private materials producers are presented. This report of the Transportation Research Board defines several measures of variability but concentrates on the use of standard deviation as the usual measure of variability. The synthesis updates reported typical variabilities found in materials and construction specifications. Also included are discussions of current research activities as related to variability, how variability can be used in the development of specification limits, the use of incentives and disincentives in specifications, and the need for additional information on the variability of several materials and construction processes.

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.

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.