| Summary: | 碩士 === 國立臺灣科技大學 === 營建工程技術學系 === 81 === From the investigation of structural failure after severe
earthquake and also from laboratory testing,it has been found
that conventional Concentrically Braced Frame (CBF) usually
suffer from strength degradation and limited ductility after
bracing member buckle. In order to improve the seismic
resistance behavior of CBF, a new system has been developed
which the buckling of bracing member can be avoided.This
bracing is called Buckling Inhibited Bracing (BIB) and the
frames contain BIB member is designated as Ductile
Concentrically Braced Frame (DCBF). Although DCBF has been
found to process good seismic resistance behavior , yet more
research has to be carried out before design guild lines can be
established. This reported the BIB member by using nonlinear
finite element method and structure testing.The following are
the preliminary findings from this study: (1) The global
buckling strength of BIB system increases with the increase of
the moment of inertial of steel bracing and its lateral
support device.The increase of lateral unsupported length will
decrease the global buckling strength of BIB system. (2) The
increase of gap width between steel bracing and its lateral
support device will decrease the strength of BIB system. (3)
The load-deformation relationship of steel bracing became
irregular as the width of gap between steel bracing and latral
support increase. (4) With the increase of axial deformation of
steel bracing,its deformation governed by higher mode
gradually. (5) Out-of-plane force of steel bracing become
larger as the width of gap between steel bracing and lateral
support increase. (6) Out-of-plane force of steel bracing
become larger as the deformation governed by higher mode. (7)
The moment of lateral support device increases with the
increase of axlal deformation and force.
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