Effectiveness of using rubber bumper and restrainer on mitigating pounding and unseating damage of bridge structures subjected to spatially varying ground motions

Abstract Pounding and unseating damages to bridge decks have been observed in almost all the previous major earthquakes. Recent studies have highlighted that adjusting the fundamental periods of adjacent structural elements close to each other, the only method suggested by the codes to mitigate pounding and unseating damage, is not sufficient to prevent such damages owing to the relative displacement induced by spatially varying ground motions. As pounding and unseating damage could lead to significant loss of economy and life owing to inability to quickly access the damaged area immediately after an earthquake, it is important to protect lifeline bridge structures. Past earthquakes have revealed that the commonly used steel cable restrainers have limited effectiveness. Additionally, only limited research has focused on mitigating pounding forces on the bridge joints that lead to localized damages and disruptions of the serviceability of the bridge after strong shakings. This study presents an extensive investigation on the effectiveness of combining rubber bumpers as a shock absorbing device along with Shape Memory Alloy (SMA) or steel cable restrainers to mitigate pounding and unseating damages on multiple-span bridges subjected to spatially varying ground motions. The responses of bridge structures with different restraining devices acting alone and in combination with rubber bumpers subjected spatially varying ground motions are compared and discussed. The result indicates that the SMA restrainers combined with rubber bumpers could lead to better performance in terms of reduction of joint opening and mitigation of large pounding forces.

[1]  J. Mander,et al.  Theoretical stress strain model for confined concrete , 1988 .

[2]  Anat Ruangrassamee,et al.  Relative displacement response spectra with pounding effect , 2001 .

[3]  Ping Zhu,et al.  Evaluation of pounding countermeasures and serviceability of elevated bridges during seismic excitation using 3D modeling , 2004 .

[4]  Mjn Priestley,et al.  Seismic Design and Retrofit of Bridges , 1996 .

[5]  J. Penzien,et al.  Multiple-station ground motion processing and simulation based on smart-1 array data , 1989 .

[6]  Masanobu Shinozuka,et al.  Effects of seismically induced pounding at expansion joints of concrete bridges , 2003 .

[7]  Nawawi Chouw,et al.  Study of SSI and non-uniform ground motion effect on pounding between bridge girders , 2005 .

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

[9]  Nawawi Chouw,et al.  Seismic design of bridge structures with allowance for large relative girder movements to avoid pounding , 2009 .

[10]  Masanobu Shinozuka,et al.  Viscoelastic Dampers at Expansion Joints for Seismic Protection of Bridges , 2000 .

[11]  Hong Hao,et al.  Numerical simulation of pounding damage to bridge structures under spatially varying ground motions , 2013 .

[12]  Jian Zhang,et al.  Effects of Pounding and Skewness on Seismic Responses of Typical Multispan Highway Bridges Using the Fragility Function Method , 2013 .

[13]  lngo Schrage,et al.  Anchoring of Bearings by Friction , 1981 .

[14]  Nawawi Chouw,et al.  Effect of abutment excitation on bridge pounding , 2013 .

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

[16]  Reginald DesRoches,et al.  Experimental response modification of a four‐span bridge retrofit with shape memory alloys , 2009 .

[17]  Kazuhiko Kawashima,et al.  Reconnaissance Report on Damage of Bridges in 2008 Wenchuan, China, Earthquake , 2009 .

[18]  E. Sacco,et al.  A Superelastic Shape-Memory-Alloy Beam Model , 1997 .

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

[20]  Reginald DesRoches,et al.  Comparison between Shape Memory Alloy Seismic Restrainers and Other Bridge Retrofit Devices , 2007 .

[21]  Praveen K. Malhotra,et al.  Dynamics of Seismic Pounding at Expansion Joints of Concrete Bridges , 1998 .

[22]  John F. Stanton,et al.  Design of Seismic Restrainers for In-Span Hinges , 1997 .

[23]  H. Hao,et al.  Pounding Damage to Buildings and Bridges in the 22 February 2011 Christchurch Earthquake , 2012 .

[24]  Hong Hao,et al.  Modelling and simulation of spatially varying earthquake ground motions at sites with varying conditions , 2012 .

[25]  Masanobu Shinozuka,et al.  Energy dissipating restrainers for highway bridges , 2000 .

[26]  A. S. Elnashai,et al.  Confined concrete model under cyclic load , 1997 .

[27]  Susan Dowty,et al.  Seismic Design Criteria , 2011 .

[28]  Nawawi Chouw,et al.  3D FEM Analysis of Pounding Response of Bridge Structures at a Canyon Site to Spatially Varying Ground Motions , 2013 .

[29]  Kazimierz Sobczyk,et al.  Stochastic wave propagation , 1985 .

[30]  Hui Li,et al.  Experimental study of a highway bridge with shape memory alloy restrainers focusing on the mitigation of unseating and pounding , 2012, Earthquake Engineering and Engineering Vibration.

[31]  Eunsoo Choi,et al.  Seismic analysis and retrofit of mid-America bridges , 2002 .

[32]  Reginald DesRoches,et al.  Seismic retrofit of simply supported bridges using shape memory alloys , 2002 .

[33]  R. Jankowski Pounding force response spectrum under earthquake excitation , 2006 .

[34]  Roberto T. Leon,et al.  FULL-SCALE TESTS OF SEISMIC CABLE RESTRAINER RETROFITS FOR SIMPLY SUPPORTED BRIDGES , 2003 .

[35]  George Deodatis,et al.  Non-stationary stochastic vector processes: seismic ground motion applications , 1996 .

[36]  Panayiotis C. Polycarpou,et al.  Numerical investigation of potential mitigation measures for poundings of seismically isolated buildings , 2011 .

[37]  Reginald DesRoches,et al.  Unseating prevention for multiple frame bridges using superelastic devices , 2005 .

[38]  Nawawi Chouw,et al.  Significance of SSI and non-uniform near-fault ground motions in bridge response II: Effect on response with modular expansion joint , 2008 .

[39]  Nawawi Chouw,et al.  Experimental investigation of spatially varying effect of ground motions on bridge pounding , 2012 .

[40]  Kenji Kosa,et al.  Damage of Bridges due to the 2010 Maule, Chile, Earthquake , 2011 .

[41]  Emmanuel A. Maragakis,et al.  Parameters in Bridge Restrainer Design for Seismic Retrofit , 1996 .

[42]  Shehata E. Abdel Raheem Pounding mitigation and unseating prevention at expansion joints of isolated multi-span bridges , 2009 .