Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Civil Engineering


It is an established fact that the number of trucks and automobile s has undergone a rapid increase since World War II and will continue to increase in the foreseeable future. This tremendous increase has strained the capabilities of the highway system over which the motor vehicles are operating. The increase in traffic, particularly heavy truck traffic, as brought about a need for a stronger but more flexible pavement which will withstand the heavy wheel loading without the maintenance problems that are common to many pavements which have been subjected to large traffic volumes and heavy wheel loads. There are two types of pavement in use at this time. The so-called “rigid” pavement which consists of a Portland cement concrete slab, acts like a beam to spread the load over the subgrade. The other type is known as a “flexible” pavement which is constructed of layers of soil materials of varying strengths. A layer of asphaltic concrete is placed on top of the layers of soil material to provide protection for the roadbed against the weathering elements, and to provide a wearing surface with good riding characteristics. Asphalt may also be used as a binder to increase the stability of some of the top layers of soil. (see more in text)

Library of Congress Subject Headings

Portland cement
Roads -- Design and construction




South Dakota State University