CHAPTER IV

ROAD DESIGN

Necessity for Planning--Road Plans--Problems of Design-- Preliminary Investigations--Road Surveys--Alignment-- Intersections--Superelevation--Tractive Resistance--Rolling Resistance--Internal Resistance--Air Resistance--Effect of Trades--Energy Loss on Account of Grades--Undulating Roads-- Guard Railing--Width of Roadway--Cross Section--Control of Erosion--Private Entrances--Æsthetics 42-62