Seismic retrofit of simply supported bridges using shape memory alloys

Recent earthquakes in the United States and Japan have highlighted the vulnerability of bridges to collapse due to excessive movement at the intermediate hinges and abutments. This study investigates the effectiveness of shape memory alloy restrainer bars to reduce the seismic vulnerability of bridges. Full-scale tests of shape memory alloy (SMA) restrainer bars are conducted to determine their force-deformation and energy dissipation characteristics. The 25.4 mm diameter bars are subjected to cyclical strains up to 8%, with minimum residual deformation. The effectiveness of the SMA restrainer bars in bridges is assessed through nonlinear analyses of a typical multi-span simply supported bridge. The SMA restrainer bars are effective in limiting the relative displacement at the piers and abutments. In addition, the bars are shown to be very effective for near-field ground motion.

[1]  L. Javier Malvar,et al.  BRIDGE RETROFIT TESTING: HINGE CABLE RESTRAINERS , 1989 .

[2]  Paul C. Jennings,et al.  Engineering features of the San Fernando earthquake of February 9, 1971 , 1971 .

[3]  Krzysztof Wilde,et al.  Base isolation system with shape memory alloy device for elevated highway bridges , 2000 .

[4]  Takuji Kobori,et al.  Proceedings of the Second World Conference on Structural Control , 1999 .

[5]  Ian G. Buckle.  The Northridge, California earthquake of January 17, 1994 : Perfomance of highway bridges , 1994 .

[6]  A. Filiatrault,et al.  The Hyogo-ken Nanbu earthquake (The great Hanshin earthquake) of 17 January 1995 , 1995 .

[7]  Reginald DesRoches,et al.  Design of seismic cable hinge restrainers for bridges , 2000 .

[8]  K. Chang,et al.  Seismic Performance of Highway Bridges , 2000 .

[9]  James M. Kelly,et al.  Experimental and analytical studies of shape-memory alloy dampers for structural control , 1995, Smart Structures.

[10]  Michel Bruneau,et al.  Performance of steel bridges during the 1995 Hyogo-ken Nanbu (Kobe, Japan) earthquake , 1996 .

[11]  E. J. Graesser,et al.  Shape‐Memory Alloys as New Materials for Aseismic Isolation , 1991 .

[12]  Steven J. Savage,et al.  ENGINEERING ASPECTS OF SHAPE MEMORY ALLOYS , 1991 .

[13]  Brian Maroney,et al.  Experimental Testing of Laterally Loaded Large Scale Bridge Abutments , 1993 .

[14]  Craig D. Comartin,et al.  The Hyogo-ken Nanbu earthquake : Great Hanshin Earthquake Disaster, January 17, 1995 : preliminary reconnaissance report , 1995 .