Parametric Analysis on the Deck’s Inplane Rotation Responses of Simply-supported Skewed Girder Bridges under Ground Motions
The deck’s inplane rotation caused by earthquakes in Simply-supported Skewed Girder Bridges(SSGB) will not only increase the longitudinal and transverse displacements of deck but also increase the probability of pounding between the girder and boundary. In order to investigate the deck’s seismic inplane rotation response of SSGB, a simplified dynamic calculation model considering the effect of pounding between the girder and boundary in SSGB was developed by OpenSees earthquake simulation platform. The effects of the longitudinal pounding stiffness, the initial gap at expansion joint, the transverse pounding stiffness, the initial gap between girder and shear keys and the mechanical characteristics of shear keys on the deck’s seismic inplane rotation of SSGB were analyzed. The results indicate that the longitudinal pounding stiffness, the initial gap at expansion joint and the transverse initial gap have significant effect on the deck’s seismic rotation of SSGB, but the transverse pounding stiffness has relatively unremarkable effect on the deck’s seismic rotation of SSGB. Setting the pads in acute angle zone of the girders’ both ends in SSGB could reduce seismic rotation angle and longitudinal displacement of the girder. Using elastic-plastic shear keys could control effectively the seismic inplane rotation angle of deck and mitigate the transverse force of shear keys in SSGB.
1. School of Civil Engineering, Shijiazhuang TieDao University, Shijiazhuang 050043, Hebei, China;
2. Key Laboratory of Roads and Railway Engineering Safety Control of Ministry of Education, Shijiazhuang TieDao University, Shijiazhuang 050043, Hebei, China;
3. Department of Bridge Engineering, Tongji University, Shanghai 200092, China
Abstract：The deck’s inplane rotation caused by earthquakes in Simply-supported Skewed Girder Bridges(SSGB) will not only increase the longitudinal and transverse displacements of deck but also increase the probability of pounding between the girder and boundary. In order to investigate the deck’s seismic inplane rotation response of SSGB, a simplified dynamic calculation model considering the effect of pounding between the girder and boundary in SSGB was developed by OpenSees earthquake simulation platform. The effects of the longitudinal pounding stiffness, the initial gap at expansion joint, the transverse pounding stiffness, the initial gap between girder and shear keys and the mechanical characteristics of shear keys on the deck’s seismic inplane rotation of SSGB were analyzed. The results indicate that the longitudinal pounding stiffness, the initial gap at expansion joint and the transverse initial gap have significant effect on the deck’s seismic rotation of SSGB, but the transverse pounding stiffness has relatively unremarkable effect on the deck’s seismic rotation of SSGB. Setting the pads in acute angle zone of the girders’ both ends in SSGB could reduce seismic rotation angle and longitudinal displacement of the girder. Using elastic-plastic shear keys could control effectively the seismic inplane rotation angle of deck and mitigate the transverse force of shear keys in SSGB.
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