29-41

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--AEsthetics 42-62

CHAPTER V

EARTH ROADS

Variations in Soils--Variation in Rainfall--Cross Sections
Elevating Grader--Maney Grader--Slip Scraper--Fresno
Scraper--Elevating Grader Work--Use of Blade Grader--
Costs--Maintenance--Value of Earth Roads 63-73

CHAPTER VI

SAND-CLAY AND GRAVEL ROADS

The Binder--Top-soil or Natural Mixtures--Sand-clay on Sandy
Roads--Sand-clay on Clay or Loam--Characteristics--Natural
Gravel--The Ideal Road Gravel--Permissible Size of Pebbles--
Wearing Properties--Utilizing Natural Gravels--Thickness
of Layer--Preparation of the Road--Trench Method--Surface
Method--Maintenance 74-88

CHAPTER VII

BROKEN STONE ROAD SURFACES

Design--Properties of the Stone--Kinds of Rocks used for
Macadam--Sizes of Stone--Earth Work--Foundation for the
Macadam--Telford Foundation--Placing the Broken Stone--
Rolling--Spreading Screenings--Bituminous Surfaces--Maintenance
Characteristics 89-97

CHAPTER VIII

CEMENT CONCRETE ROADS

Destructive Agencies--Design--Concrete Materials--Fine
Aggregate--Proportions--Measuring Materials--Preparation of the
Earth Foundation--Placing Concrete for Two-course Road--Curing
the Concrete--Expansion Joints--Reinforcing--Bituminous Coatings
on Concrete Surfaces--Characteristics--Maintenance 98-105

CHAPTER IX

VITRIFIED BRICK ROADS

Vitrified Brick--Paving Brick--Repressed Brick--Vitrified Fiber
Brick--Wire-cut-lug Brick--Tests for Quality--Other Tests--
Foundation--Sand Bedding Course--Sand Mortar Bedding Course--
Green Concrete Bedding Course--Bituminous Fillers--Mastic
Fillers--Marginal Curb 106-115

CHAPTER X

BITUMINOUS ROAD MATERIALS AND THEIR USE

Classes of Bituminous Materials--Coal Tar--Water Gas Tar--Natural
Asphalt--Petroleum Asphalt--Mixtures--Classification According to
Consistency--Road Oils--Liqu