The following have contributed to this book. Where a name is shown in bold, he or she is a contributor to one of the main chapters. Where a name is shown in bold and italics, the person was a contributor to one of the main chapters but not a member of the COST 351 project. Special thanks is due to these authors for being external contributors to the book. The others listed were members of the COST 351 project team but their contribution has not been separately identified. This doesn’t
mean that it was an unimportant part__ in several cases these people have made
major contributions in editing, providing material, organizing the appendices, etc. Some of those listed only participated in the COST 351 Action for a short period. Particular recognition is due to those who helped establish the direction of the study but were then unable to continue to the final stages of which this book is the principal result.
Andrew Dawson
Abstract This introduction provides a brief review of the history of highway subdrainage before setting out the aims and organisation of the book of which it forms the first chapter. It gives an overview of the subjects to be covered in the following chapters, introduces the key topics including definitions of subgrade and pavement layers, their classification from a drainage point-of-view together with a brief coverage of the principle of effective stress, suction, leaching and water movement due to evaporation and frost-heave. It outlines the way in which pavements and the hydrological environment interact before introducing the reader to the varieties of climate in which highways and pavements have to operate — a task that is likely to become more onerous in the light of climate change effects.
Keywords Introduction ■ history ■ definition ■ drainage classification of pavements ■ alternative materials ■ drainage systems ■ climate
