The first edition of this book (Handbook of Road Technology Fourth Edition by M. G. Lay) was based in significant part on my earlier Source Book for Australian Roads (Lay, 1985a), with the text edited and expanded to suit an international audience.
Subsequent editions have been revised in the light of new published work, reader feedback, my continued experience as a road practitioner and my own improved understandings. All this work has been done in my own time, but I acknowledge the ongoing support of my various employers, colleagues and clients over the last 23 fascinating years.
This fourth edition has been partly prepared during my periods as a principal engineer at Sinclair Knight Merz responsible for reviewing all aspects of the mammoth City Link buildown-operate-transfer (BOOT) toll-road project, as an advisor to the construction firm Thiess preparing bids for toll road projects, and finally as a Director of the Macquarie Bank company, ConnectEast responsible for the design, construction and operation of the EastLink toll road.
All these experiences, which have added many practical and commercial facets to my existing theoretical and design knowledge, have greatly influenced this fourth edition. Many of the changes also arise from reader feedback on the update pages published in Highway Engineering in Australia until the end of 2007.
Given my objectives, the book (Handbook of Road Technology Fourth Edition by M. G. Lay) draws heavily on the work of others. Much of the material is not my own. To avoid presentation difficulties, it has not always been possible to acknowledge this in detail.
The aim is to present available data in collected, collated and readable form, rather than to create new knowledge. Any perceived inadequacies in the referencing may thus be a result of deliberate policy, rather than laziness on my part.
I particularly apologise if this has occasionally led to some imprecision or undesirable omission in the referencing of the work of others. It was either unintentional or unavoidable. I do wish to acknowledge all those whose work I have drawn on so extensively to write this book.
To you, my reader of this new edition, may I acknowledge in advance the comments that you send me on how future editions might be improved and enhanced. However, my prime thanks must continue to go to my wife Margaret for her patience and understanding.
Robbie and Cosette, with restraint, have kept their feet on the ground and off my papers. Grandchildren have provided many unexpected but essential distractions from the underlying tedium.
I have found writing and updating the book through all its versions to this fourth edition to be a rewarding and pleasant experience. I hope that in using it you may share some of my satisfaction.