"This synthesis will be of interest to administrators and policy makers; pavement, material, geotechnical, and environmental engineers; and maintenance and construction professionals involved with highway design and construction issues. Information is provided on the technical, economic, and environmental aspects (including legislative and regulatory considerations) of recycling and using waste materials and by-products in highway construction. The quantities, characteristics, possible uses, current and past research activities, and actual highway construction use of each waste material or by-product is provided. This information, based on a review of nearly 1,000 references and on responses to a 1991 survey (updated in 1993), is classified into four broad categories based on source: agricultural, domestic, industrial, and mineral wastes. A Technical Appendix to this document containing an extensive bibliography, supporting information, and details regarding the use of selected waste materials and by-products is available separately from the Transportation Research Board."--Avant-propos.
This report gives an overview and summarizes the results of the research conducted under the four geotechnical projects established during the 1970's. It describes the efforts and results of 25 years of research spanning three decades from 1973-1998. The main purpose of the report is to provide a summary of the FHWA geotechnical research activities over the last quarter of the 20th century. It is intended for the general engineers and administrative managers of FHWA and the SHA's. Also presented are descriptions of the various problems that were addressed; and the report discusses the objectives and scope of each project in detail, except for the Tunneling Project, which is reported elsewhere (see appendix B). A review of each project's organization and approach is presented before the results are noted and evaluated. Technology transfer and future research needs are also covered separately to highlight the important nature of each topic.
Recognizing the burden that reinforcing steel corrosion imposes on natural resources, the Federal Highway Administration established Corrosion Protection for Concrete Bridges as one of the high-priority areas (HPAs) in its Structures Research Program. This report summarizes the progress made through research efforts conducted under these programs. The results presented cover (A) corrosion control in new concrete constructions (adequate concrete cover, quality concrete, rebar coatings, corrosion inhibiting admixtures, and corrosion protection of prestressed concrete bridge members) and (B) corrosion control for rehabilitation of existing concrete structures (conventional rehabilitation methods, cathodic protection, and electrochemical removal of chloride).