Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Civil Engineering

First Advisor

Arden B. Sigl


In 1980, at the request of the South Dakota Department of Transportation (SDDOT), a study was undertaken to determine the probable cause of a specific type of cracking that was observed in a series of concrete box girder bridges. The study, "Investigation of the Cause of Observed Cracks in a Series of Concrete Box Girder Bridges", was conducted by Dr. Arden B. Sigl and Steven M. Bjordahll. In addition to the cracking, the end abutments had shifted in a translatory mode toward the girders. The abutments were analyzed to determine if the abutment movements_ observed could be expected for the loads that the bridge could be expected to resist. This was included since the movement was toward the girders which closed the expansion joints and subjected the bridge girder to a loading for which they were not designed. This study is performed in an attempt to expand on these movements and to draw more concise conclusions on the probable cause of the movement. These bridges were constructed during the years 1958 to 1961. Since 1969, the bridges have been inspected every two years. Documentation of the inspections are cataloged by the SDDOT and were used in the 1980 study. As stated in Section 1.1, a study was performed to examine the probable causes of the cracks in the girders, with the abutment translations cited as a secondary problem. A computer model of the abutments was utilized to determine what translations could be expected to occur for the loads and conditions that the abutments were likely to have experienced. The results were then compared to the findings obtained in the site inspections. A summary of the conclusions will be discussed later in Section 3.4. In order to expand on the findings of the 1980 study, a more refined computer analysis was developed for this study. These results were compared to the site observations and findings of the 1980 study. Conclusions have been drawn as to what has likely caused the movements.

Library of Congress Subject Headings

Bridges -- Abutments

Box girder bridges

Concrete bridges



Number of Pages



South Dakota State University