This thesis represents a portion of the research conducted as part of an investigation for the California Department of Transportation (Caltrans) regarding the seismic response and overall moment capacity of precast I-girder to inverted-T bent cap bridge connections for seismic applications. The current design practice, as outlined by Caltrans' Seismic Design Criteria, assumes that the connection between the precast I-girders and the inverted-T bent cap will degrade in a seismic event and shall therefore be designed as a pinned connection, making the precast girder option for seismic bridges inefficient. A prototype I-girder to inverted-T bent cap bridge and a 50% scale test unit was designed in order to investigate the behavior of the girder-to-cap connection region. Additionally, per the request of Caltrans, an improved girder-to-cap connection detail was developed in order to ensure a fully continuous moment connection between the I-girders and inverted-T bent cap.
A finite element grillage model was developed using SAP2000 and was used to predict the global and local responses of various aspects of the test unit. The test unit was constructed and tested in two phases of quasi-static cyclic testing. The first phase was a horizontal load test phase, which simulated the effects of gravity and seismic loads on the entire test unit. The second phase was a vertical load test phase, which specifically focused on the positive and negative moment capacity of the connection. Both the results of the finite element grillage model and the testing were used to make conclusions regarding the performance of I-girder to inverted-T bent cap bridges.
It was concluded that the current I-girder to inverted-T bent cap bridge connection is capable of acting as a fully continuous connection for both positive and negative moments during both gravity and seismic loading, contrary to the design assumptions stated in Caltrans' Seismic Design Criteria. The improved connection detail demonstrated the ability to ensure a fully continuous moment connection between the I-girders and inverted-T bent cap. Both connection details also exhibited a significant moment resistance beyond what was expected, during the vertical load test.
Some files may require a special program or browser plug-in. More Information
|Commitee:||Fanous, Fouad, Schmerr, Lester|
|School:||Iowa State University|
|Department:||Civil, Construction, and Environmental Engineering|
|School Location:||United States -- Iowa|
|Source:||MAI 49/03M, Masters Abstracts International|
|Keywords:||Bridge, Connection, Grillage, I-girder, Seismic, inverted-T|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be