09-07-2012, 12:48 PM
RESEARCH AND DEVELOPMENT ON SEISMIC DESIGN METHOD
FOR PRECAST CONCRETE BRIDGE COLUMNS
RESEARCH AND DEVELOPMENT ON SEISMIC DESIGN.pdf (Size: 451.19 KB / Downloads: 125)
Introduction
With a background of the generalization of the performance-based design concept
into practices, the applications of new materials, new designs, and new structures have
started to be actively employed with necessary performance verifications. PRE-Columns
are one of such new applications. PRE-Columns effectively use the combination of high
strength materials including steels and concrete. The precast segments, which are produced
at factory, for PRE-Columns can be easily achieved to have better-quality. Therefore,
PRE-Columns are expected to improve the constructionability at sites and shorten the
construction period.
Research on Dynamic Performance of Proposed PRE-Columns
In order to obtain the data on the failure mechanism, the strength and ductility
performance, and the dynamic behavior of proposed PRE-Columns, as well as in order to
develop the design method, a series of dynamic loading tests and shaking table tests were
made. In this paper, some of the research results are introduced.
Shake Table Tests and the Analytical Simulation
Shake table tests have been made to verify the dynamic performance of
PRE-Columns. Objectives of the tests are to have the data on earthquake response
characteristics and failure mechanism. Since, in particular, PRE-Columns 1 and 2 use the
PC cables as longitudinal re-bars, the effect of PC cables on the dynamic behavior was one
of the points. Figure 5 shows the typical example of the nonlinear force-displacement
relation of PRE-Columns with PC tendons. It is of the PRE-Column 2 and was obtained
through the cyclic loading tests. The force-displacement relation is different with usual
reinforced concrete and the displacement tends to recover toward the origin when the force
is released, then the hysteresis energy absorption is relatively smaller than usual reinforced
concrete columns.
Conclusions
The research on the seismic design methods for PRE-Columns was introduced in
this paper. A series of cyclic loading tests, shaking table tests, and analytical study were
made. The seismic design guidelines for proposed PRE-Columns are now being developed
and will be published in 2008.