Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil Engineering

First Advisor

Vernon R. Schaefer


Over the past few decades increased public attention and concern has been focused on waste disposal. Historical practices included disposal in un-engineered dumps, which threatened human health and the environment and sparked an evolution in disposal facility engineering beginning in the 1950's and continuing to the present. As regulations were passed to protect the environment, disposal facilities transformed from dumps to engineered landfills. Increasingly, compacted clay has been used as a liner to separate waste from natural ground. Wet-dry cycling, resulting in crack formation in compacted clay, is commonly experienced during liner construction and throughout the lifetime of a disposal facility cover. Laboratory tests show that wet-dry cycling leads to increases in hydraulic conductivity of as much as two orders of magnitude. Moreover, hydraulic conductivity of samples compacted at optimum moisture content increase significantly more due to wet-dry cycling than samples compacted three percent wet of optimum moisture content.

Library of Congress Subject Headings

Clay soils -- Permeability -- Testing
Clay soils -- Drying
Sanitary landfills -- Linings




South Dakota State University



Rights Statement

In Copyright