Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil and Environmental Engineering

First Advisor

Junwon Seo


Analytical Model, Distribution Factors, Double Tee Bridge, Dynamic Load Allowance, Field Test


Two deteriorating DT bridges in South Dakota, both over 30-years old, were field tested with a static and dynamic load. From the recorded strain values, the liveload distribution factors (LLDFs) and dynamic load allowance (IM) factors were calculated. The AASHTO LRFD and AASHTO Standard Specifications were compared with the field LLDFs and IMs. It was determined that the AASHTO LRFD Specifications were conservative for deteriorating DT girder bridges, with two exceptions. The AASHTO Standard codified LLDFs were significantly higher than the field LLDFs in all cases. The AASHTO LRFD and AASHTO Standard specifications were conservative when calculating the IM factors in all instances for the two deteriorating DT bridges. The strain data from the field tests was analyzed for LLDFs in three different approaches. Then, these approaches were compared to AASHTO LRFD and AASHTO Standard specifications. The girder approach had an average percent difference of 34% and 91% when compared to the AASHTO LRFD and AASHTO Standard specifications, respectively. The joint approach produced average percent differences similar to the girder approach. The stem approach was the most conservative approach, with an average percent difference of 58%, compared to AASHTO LRFD.

Library of Congress Subject Headings

Concrete bridges -- South Dakota -- Testing.
Prestressed concrete bridges -- South Dakota -- Testing.
Precast concrete construction.



Number of Pages



South Dakota State University



Rights Statement

In Copyright