J. Padgett, Rice University, Houston, TX; R. DesRoches, Georgia Institute of Technology, Atlanta, GA; D. E. Hodgson, Nitinol Technology, Inc., Mountain View, CA
This paper presents a unique application of shape memory alloys for seismic rehabilitation (retrofit) of bridges, by exploiting the recentering and energy dissipating properties of the superelastic SMA’s. Bridge damage due to large displacements and deck unseating has been observed in many earthquakes, and recent events have illustrated that conventional steel restrainer cable retrofits may lack the deformation capacity to adequately restrain bridges. The efficacy of new SMA recentering, or restraining, devices is evaluated through large scale testing of a near full-scale, four-span bridge at the University of Nevada, Reno Laboratory. Testing of the bridge retrofit with these innovative devices allows evaluation of their performance in both reducing the displacements at the abutments and reducing the overall demands on bridge columns. Large-scale validation, as provided by this study, is the first step towards acceptance of this class of materials for seismic retrofit of bridges.
Summary: This paper presents a unique application of shape memory alloys for seismic rehabilitation (retrofit) of bridges, by exploiting the recentering and energy dissipating properties of the superelastic SMA’s. Bridge damage due to large displacements and deck unseating has been observed in many earthquakes, and recent events have illustrated that conventional steel restrainer cable retrofits may lack the deformation capacity to adequately restrain bridges. The efficacy of new SMA recentering, or restraining, devices is evaluated through large scale testing of a near full-scale, four-span bridge at the University of Nevada, Reno Laboratory. Testing of the bridge retrofit with these innovative devices allows evaluation of their performance in both reducing the displacements at the abutments and reducing the overall demands on bridge columns. Large-scale validation, as provided by this study, is the first step towards acceptance of this class of materials for seismic retrofit of bridges.
