Road - INTRODUCTION
TYPES OF ROADS
Highways
Urban Streets
Rural Roads
ROADWAY ENGINEERING
Roadbed
Base Course
Wearing Course
Bituminous Pavement
Concrete Pavement
ROAD PLANNING AND ADMINISTRATION
HISTORY OF ROAD CONSTRUCTION


AUTOMOBILE
AUTOMOBILE INDUSTRY
PUBLIC TRANSPORTATION
TRUCK


ROADWAY ENGINEERING






Highway Construction | Flexible and Rigid Pavements | Truck Slowly | Heavy Rollers


To support heavy vehicles moving at high speeds, a modern road is made up of several layers. Each layer helps the layers above it support the weight and pressure of moving traffic. Roads that carry more traffic at higher speeds, like highways, are built to stronger standards than roads that carry less traffic, such as rural collector roads. The number of layers in a road often depends on the intended use of the road, but generally roads have three distinct layers. From bottom to top, the layers are the roadbed, the base course, and the wearing course. (ROADWAY ENGINEERING, Highway Construction, Flexible and Rigid Pavements, Truck Slowly, Heavy Rollers)
Highway Construction, Flexible and Rigid Pavements

Flexible and rigid pavements each contain several different layers of materials. The layers below combine to support the traffic moving along on the surface layer, which is known as the wearing course. Asphalt makes up the wearing course of flexible pavement and is often found on residential streets in cities. Rigid pavement made of concrete is more durable and is a popular choice for highway construction. (ROADWAY ENGINEERING, Highway Construction, Flexible and Rigid Pavements, Truck Slowly, Heavy Rollers)
Truck Slowly, Heavy Rollers

In order to withstand the constant wear from traffic and weather, roads must be carefully built with level, durable foundations and surfaces. Here, a large truck slowly lets out its load of gravel onto a new road bed. Gravel acts as part of the foundation and will be groomed and pressed by heavy rollers before the asphalt layer is added. (ROADWAY ENGINEERING, Highway Construction, Flexible and Rigid Pavements, Truck Slowly, Heavy Rollers)

ROADWAY ENGINEERING | Highway Construction | Flexible and Rigid Pavements | Truck Slowly | Heavy Rollers