This new edition of the handbook has been updated throughout to reflect continuing changes and improvements in design trends and specifications. The chapter on bridge engineering has been revised to provide more comprehensive treatment of this important topic. The chapter on culverts and drainage provides updated hydraulic design information as well as the latest approved methods for the structural design of concrete, steel, and plastic pipes. The chapter on retaining walls has been expanded with new information on mechanically stabilized earth walls, including a section on bridge abutment walls. Significant new information has been added to the chapter on value engineering to reflect the current roles of the Federal Highway Administration (FHWA) and the American Association of State Highway and Transportation Engineers (AASHTO); additional examples of applications have been included, too.
Regrettably, this edition of the handbook marks the passing of Kenneth Boedecker, a friend and colleague active in highway engineering applications for many years. His contributions, particularly in the development of improved specifications for drainage pipe and other products, are gratefully acknowledged.
Finally, the reader is cautioned that independent professional judgment must be exercised when information set forth in this handbook is applied. Anyone making use of this information assumes all liability arising from such use. Readers are encouraged to use the latest edition of the referenced specifications, because they provide more complete information and are subject to frequent change.
Roger L. Brockenbrough, P. E.
