Seismic response analysis of offshore isolated bridge based on performancedegradation of high damping rubber bearing and pier(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年2期
- Page:
- 23-33
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Seismic response analysis of offshore isolated bridge based on performancedegradation of high damping rubber bearing and pier
- Author(s):
- MA Yuhong1; 2; QIU Jiepeng1; 2; LIU Yongqi2; 3; ZHAO Guifeng2; 3
- (1. Earthquake Engineering Research & Test Center, Guangzhou University, Guangzhou 510405, Guangdong,China; 2. Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology,Guangzhou University, Guangzhou 510405, Guangdong, China; 3. School of Civil Engineering,Guangzhou University, Guangzhou 510006, Guangdong, China)
- Keywords:
- bridge engineering; offshore isolated bridge; highdamping rubber bearing; performance degradation; timevarying seismic performance
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to study the influence of performance degradation of highdamping rubber bearings and material of pier on seismic performance of offshore isolated bridges during service period, and provide a theoretical basis for the evaluation of the whole life performance of offshore isolated bridges, a performance degradation test of highdamping rubber bearings was firstly carried under the action of seawater drywet cycles, and a corresponding timevarying model of mechanical performance degradation was obtained. The timevarying parameters of mechanical performance of highdamping rubber bearings were given during the whole life cycle. Based on the degradation model of the mechanical performance of steel bar and concrete material, the timevarying parameters of steel bar and concrete were calculated during the whole life cycle. The timevarying law of flexural bearing capacity and ductility of pier section was analyzed during the fulllife cycle under three working conditions, longitudinal reinforcement deterioration, stirrup deterioration and both deterioration. Subsequently, a nonlinear finite element model of offshore isolated bridge was established in SAP2000 software, and three working conditions were designed, including pier degradation, bearing degradation, pier and bearing degradation together. The timevarying law of bridge seismic responses were analyzed and compared under different conditions. The results show that the deterioration of stirrup leads to a significant decrease in ductility of the pier section, but has little effect on flexural bearing capacity of the section, while the deterioration of longitudinal reinforcement is on the contrary. The common deterioration of longitudinal reinforcement and stirrup makes the bending resistance and ductility of pier section significantly decrease. Separate deterioration of pier and bearing have effects on both pier response and hysteresis curve of bearing. Compared with the single deterioration of bearing performance and pier material, the joint action of two has the greatest influence on the seismic response of pier and bearing hysteretic curve. With the increase of service time, the displacement at the top of pier and bending momentturn angle hysteretic area at the bottom of pier increases gradually, but the moment at the bottom of the pier and the hysteretic area of bearings decreases. The seismic performance of isolated bridge is greatly affected by extremely rare earthquakes. Under the extremely rare earthquakes, the seismic response of pier and bearing is significantly increased. 2 tabs, 19 figs, 23 refs.
Last Update: 2021-04-02