Sun Z.,Dalian Maritime University |
Sun Z.,Key Laboratory of Highway Engineering |
Wang D.,Dalian Maritime University |
Wang D.,Key Laboratory of Highway Engineering |
And 2 more authors.
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2013
Research on seismic behavior of RC thin-walled hollow bridge piers is of great significance to the seismic safety of large bridges. Two rectangular RC thin-walled hollow pier specimens were designed and tested. One specimen was subjected to constant axial load and cyclic lateral displacements, and the other was subjected to varying axial load and cyclic lateral displacements. The test results indicate that flexural and shear concrete cracks developed firstly and then concrete spalling and longitudinal bar buckling were observed in regions close to the bottom of specimens. The ultimate performance of specimens is dominated by local compression flange buckling failure of pier walls and specimens may collapse suddenly. The shear strength analysis models from bridge seismic design codes and literatures were evaluated and compared based on available test results for RC thin-walled hollow bridge piers. It is found that both Chinese bridge seismic design code and Eurocode 8 code give good or conservative predictions for shear strength of specimens, and hence they are applicable to the seismic design of thin-walled hollow bridge piers. However, the UCSD and Aschhiem models may overestimate the shear strength of specimens so that they could be inappropriate to the shear strength analysis of piers. Comparatively, the proposed modified UCSD model may predict the shear strength of thin-walled piers very well, while the Modified Compression Field Theory (MCFT) gives the most accurate predictions of shear strength for the piers with thin walls.
Sun Z.-G.,Dalian Maritime University |
Sun Z.-G.,Key Laboratory of Highway Engineering |
Hua C.-J.,Dalian Maritime University |
Hua C.-J.,Key Laboratory of Highway Engineering |
And 4 more authors.
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2015
Buckling-restrained brace (BRB) made of low yield strength steel is an energy dissipation damper, which can yield in tension and compression without buckling. BRB added to an RC bridge bent will yield and dissipate seismic energy prior to the bent itself with reasonable design, and the seismic risk to the bent will be decreased. The damaged BRB can be easily replaced and is designed as a structural fuse. A preliminary seismic design method based on the structural fuse concept was proposed, and the seismic damage control effect of BRB on the bent was verified by quasi-static and incremental dynamic analysis. It is found that the length of the BRB core is the key influencing factor on the yield sequence of the bent. A properly designed BRB would yield before the bent and dissipate most of the seismic energy through hysteretic behavior of the fuse while avoiding damage to the bent itself. The strength and lateral stiffness of the bent are improved, and the yielding of the transverse beam and pier is delayed. Also, the deformation demand of the bent is decreased by using BRB. © 2015, Chinese Vibration Engineering Society. All right reserved.