Summary: | As part of a research program on the seismic behaviour and retrofit of existing
bridges, this investigation was designed to focus on column-cap beam joint regions.
During the initial planning stages, a related investigation was sponsored by the Ministry of Transportation and Highways of BC to perform slow cyclic loading on large scale models of the Oak St. Bridge two-column bents. Therefore it was decided that this investigation would focus on the column-cap beam joints of the Oak St. Bridge, so that the results would have applicability to the actual bridge, and at the same time comparisons would be available between the joint tests of this investigation, and the full bent tests of the Ministry
investigation. The joint tests described in this investigation comprise tests of half the two column bent, or “half bent test”.
This investigation consists of the design of a test frame suitable for the half bent
tests and other in plane load tests on structural assemblies such as concrete joints and their connecting members, a slow cyclic test on a 0.45 scale model of half of one of the Oak St. Bridge bents as originally constructed, and a slow cyclic test on a similar model retrofitted
by post-tensioning. The latter duplicates one of the retrofit schemes also tested in the Ministry sponsored program on a 0.45 scale model of the full bent. The test frame proved suitable for the test program and for similar future testing. With a variety of options available for application of in-plane loading and restraints, it is
capable of testing large scale specimens of realistic sizes for bridges and buildings. In the tests described in this thesis, it demonstrated the potential ability to duplicate the essential behaviour of the more expensive full bent tests.
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