scholarly journals Incremental dynamic analysis of the long-span continuous beam bridge considering the fluctuating frictional force of rubber bearing

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Man Liao ◽  
Bin Wu ◽  
Xianzhi Zeng ◽  
Kailai Deng

AbstractIn the seismic design of long-span bridges, the classic bi-linear model was used to simulate the frictional restoring force of the rubber bearings. However, in actual earthquake, the rubber bearing suffered fluctuating axial pressure in earthquake, even separated from the beam when vertical component of the earthquake was too strong. Employing the bi-linear model for the bearing may incorrectly estimate the seismic response of the bearings, as well as the whole bridge. This paper developed a nonlinear frictional bearing model, which can consider the variation of the frictional restoring force in the bearings, even the separation with the beam in vertical directions. A typical continuous beam bridge was modeled in ABAQUS, and incremental dynamic analysis was conducted for the quantitative comparison of the seismic responses using different bearing models. The intensity measure was selected as the ratio of the peak ground acceleration (PGA) in the vertical direction to the PGA in the horizontal direction. The analysis results indicated that the different bearing model led to the significant different seismic response for the bearings and piers, even the vertical component was small. The bi-linear bearing model would underestimate the seismic demand of the bearing and piers.

2021 ◽  
Vol 276 ◽  
pp. 02030
Author(s):  
Wang Yanan ◽  
Tang Guangwu ◽  
Liu Haiming ◽  
Wang Fujie ◽  
Chen yuan

In order to study the influence of far-field long-period seismic waves on high-pier and long-span continuous beam bridge, taking a high-pier and long-span continuous beam bridge with span arrangement of (95+170+95) m as an example, a numerical analysis model is established based on finite element software. According to the established wave selection criterion, 10 far-field long-period seismic records and 10 ordinary seismic records are selected from the strong earthquake record database. Using nonlinear time history analysis method, the difference of seismic response of long-span continuous beam bridge with isolated high piers under the action of ordinary ground motion and far-field long-period ground motion is studied. The results show that compared with the ordinary ground motion, the seismic response of long-span continuous beam bridge with isolated high piers is obviously increased under the action of long-period ground motion in the far field. When building isolated long-span bridges in areas with great influence of long-period ground motion in the far field, attention should be paid to the adverse effects caused by the frequency spectrum characteristics of ground motion.


2020 ◽  
Vol 2020 ◽  
pp. 1-22
Author(s):  
Yumin Zhang ◽  
Jiawu Li ◽  
Lingbo Wang ◽  
Hao Wu

Rubber isolation bearings have been proven to be effective in reducing the seismic damage of bridges. Due to the different characteristics of isolation bearings, the mechanical properties of bridges with different combinations of rubber bearings are complex under the action of earthquakes. This paper focuses on the application of combinations of rubber isolation bearings on seismic performance of continuous beam bridges with T-beams. The seismic performances of continuous beam bridges with different combinations of rubber isolation bearings, pier height, and span length were studied by the dynamic time history analysis method. It was found that the bridges with natural rubber bearings (NRBs) have the largest seismic responses compared to the other types of bearings. The continuous beam bridge with isolation bearings, such as lead rubber bearings (LRBs) and high damping rubber bearings (HDRBs), has approximately 20%∼30% smaller seismic response than that with NRBs under the action of earthquakes due to the hysteretic energy of the bearings, indicating that the isolation bearings improve the seismic performance of the bridge. The continuous beam bridges with both NRBs and LRBs or NRBs and HDRBs have larger seismic response of the piers than those with a single type of isolation bearings (LRBs or HDRBs) but smaller seismic response of the piers than those with only NRBs. For a continuous beam bridge with shorter span and lower pier, it is not economical to use LRBs or HDRBs underneath every single girder, but it is more reasonable to use cheaper NRBs underneath some girders. The larger difference in stiffness of the bearings between the side and middle piers leads to the more unbalanced seismic response of each pier of the bridge structure. The results also show that with increasing pier height and span length, the difference in the seismic response value between the cases gradually increases.


2018 ◽  
Vol 8 (5) ◽  
pp. 669 ◽  
Author(s):  
Hongye Gou ◽  
Wen Zhou ◽  
Yi Bao ◽  
Xiaobin Li ◽  
Qianhui Pu

Sign in / Sign up

Export Citation Format

Share Document