Probabilistic seismic fragility and loss analysis of concrete bridge piers with superelastic shape memory alloy-steel coupled reinforcing bars

2020 ◽  
Vol 207 ◽  
pp. 110229 ◽  
Author(s):  
Nailiang Xiang ◽  
Xu Chen ◽  
M. Shahria Alam
2019 ◽  
Vol 14 (01) ◽  
pp. 2050001
Author(s):  
Jize Mao ◽  
Daoguang Jia ◽  
Zailin Yang ◽  
Nailiang Xiang

Lack of corrosion resistance and post-earthquake resilience will inevitably result in a considerable loss of function for concrete bridge piers with conventional steel reinforcement. As an alternative to steel reinforcement, shape memory alloy (SMA)-based reinforcing bars are emerging for improving the seismic performance of concrete bridge piers. This paper presents an assessment of concrete bridge piers with different reinforcement alternatives, namely steel reinforcement, steel-SMA hybrid reinforcement and SMA reinforcement. The bridge piers with different reinforcements are designed having a same lateral resistance, or in other words, the flexural capacities of plastic hinges are designed equal. Based on this, numerical studies are conducted to investigate the relative performance of different bridge piers under seismic loadings. Seismic responses in terms of the maximum drift, residual drift as well as dissipated energy are obtained and compared. The results show that all the three cases with different reinforcements exhibit similar maximum drifts for different earthquake magnitudes. The SMA-reinforced bridge pier has the smallest post-earthquake residual displacement and dissipated energy, whereas the steel-reinforced pier shows the opposite responses. The steel-SMA hybrid reinforcement can achieve a reasonable balance between the residual deformation and energy dissipation.


2018 ◽  
Vol 29 (18) ◽  
pp. 3598-3613 ◽  
Author(s):  
Baikuntha Silwal ◽  
Qindan Huang ◽  
Osman E Ozbulut ◽  
Mojtaba Dyanati

Superelastic viscous damper is a passive hybrid control device that combines shape memory alloy cables and a viscoelastic damper to mitigate dynamic response of structures subjected to multi-level seismic hazards. In the hybrid device, shape memory alloy cables that exhibit a nonlinear but elastic response are used mainly as re-centering unit, while the viscoelastic damper composed of high-damped butyl rubber compounds is employed to augment the equivalent viscous damping provided by the device. This study evaluates the effectiveness of superelastic viscous dampers in mitigating seismic response of steel frame structures through a probabilistic framework. First, a nine-story steel frame building is designed and modeled with and without superelastic viscous dampers, and extensive nonlinear response-history analyses are conducted. Then, probabilistic demand models are developed for selected engineering demand parameters. To quantitatively compare the performance of the designed buildings, seismic fragility curves and mean annual frequency of exceeding different performance levels are developed. In particular, the structural performance is evaluated using both peak inter-story drift and residual drift responses. Results indicate that superelastic viscous dampers can significantly improve structural performance; thus, it has the potential to lower the post-earthquake losses, as the better structural performance leads to less loss in relocation, rental, and economic loss.


2020 ◽  
Vol 214 ◽  
pp. 110651 ◽  
Author(s):  
Cheng Fang ◽  
Dong Liang ◽  
Yue Zheng ◽  
Michael C.H. Yam ◽  
Ruiqin Sun

Sign in / Sign up

Export Citation Format

Share Document