scholarly journals Life-Cycle Seismic Fragility Assessment of Existing RC Bridges Subject to Chloride-Induced Corrosion in Marine Environment

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Sicong Hu ◽  
Zheyan Wang ◽  
Yu Guo ◽  
Gui Xiao
Keyword(s):  
Marine Environment ◽  
Longitudinal Direction ◽  
Seismic Damage ◽  
Assessment Method ◽  
Seismic Fragility ◽  
Damage Distribution ◽  
Seismic Performance Assessment ◽  
Tidal Zone ◽  
Damage Probability ◽  
Chloride Induced Corrosion

Bridges in a marine environment have been suffering from the chloride attack for a long period of time. Due to the fact that different sections of piers may be exposed to different conditionals, the chloride-induced corrosion not only affects the scale of the deterioration process but also significantly modifies over time the damage propagation mechanisms and the seismic damage distribution. In order to investigate the seismic damage of existing RC bridges subject to spatial chloride-induced corrosion in a marine environment, Duracrete model is applied to determine the corrosion initiation time of reinforcing steels under different exposure conditionals and the degradation models of reinforcing steels, confined concrete, and unconfined concrete are obtained based on the previous investigation. According to the seismic fragility assessment method, the damage assessment approach for the existing RC bridges subject to spatial chloride-induced corrosion in a marine environment is present. Moreover, a case study of a bridge under two kinds of water regions investigated the influence of spatial chloride-induced corrosion on the seismic damage of piers and other components. The results show that the spatial chloride-induced corrosion may result in the section at the low water level becoming more vulnerable than the adjacent sections and the alteration of seismic damage distribution of piers. The corrosion of pier will increase the seismic damage probability of itself, whereas it will result in a reduction of seismic damage probability of other components. Moreover, the alteration of seismic damage distribution of piers will amplify the effect. Due to the fact that the spatial chloride-induced corrosion of piers may alter the yield sequence of cross section, it then affects the seismic performance assessment of piers. A method to determine the evolution probability of yield sequence of corroded piers is proposed at last. From the result, the evolution probability of yield sequence of piers in longitudinal direction depends on the relationship between the height of piers and submerged zone. Moreover, the height of piers, submerged zone, and tidal zone have a common influence on the evolution of yield sequence of piers in transversal direction.

The Chloride Ion Penetration Model Coupled with Temperature and Moisture Transfer in Marine Environment

2012 ◽  
Vol 591-593 ◽  
pp. 2422-2427
Author(s):  
Juan Zhao
Keyword(s):  
Marine Environment ◽  
Moisture Transfer ◽  
Regional Climate ◽  
Chloride Ion ◽  
Chloride Penetration ◽  
Chloride Diffusion ◽  
Tidal Zone ◽  
Analog Simulation ◽  
Chloride Ion Penetration ◽  
Ion Penetration

Considering the complexity of the chloride ion penetration in concrete exposed to marine environment, an integrated chloride penetration model coupled with temperature and moisture transfer is proposed. The governing equations and parameters embody fully the cross-impacts among thermal conduction, moisture transfer and chloride ion penetration. Furthermore, the four exposure conditions are classified based on the different contact with the aggressive marine environment, and then the micro-climate condition on the concrete surface is investigated according to the regional climate characteristics, therefore, a comprehensive analog simulation to the chloride penetration process is proposed. To demonstrate that the proposed numerical model can correctly simulate the chloride diffusion in concrete, the integrated chloride diffusion model is applied in reproducing a real experiment, finally the model gives good agreement with the experimental profiles, and it is proved the tidal zone exposure results in a more severe attack on the reinforcement

Seismic Damage Assessment of Urban Water Supply Pipeline

2013 ◽  
Vol 316-317 ◽  
pp. 723-726
Author(s):  
Jian Qun Jiang ◽  
Xiao Wen Yao ◽  
Yi Ting Lu
Keyword(s):  
Water Supply ◽  
Damage Assessment ◽  
Longitudinal Direction ◽  
Underground Water ◽  
Seismic Damage ◽  
Pipeline System ◽  
Seismic Damage Assessment ◽  
Water Pipeline ◽  
Ground Condition ◽  
Water Supply Pipeline

Water supply pipeline system is a key issue in urban lifeline engineering, and the seismic assessment for the system damage is of significant importance. In this study, method of seismic damage assessment on underground water supply pipeline is introduced. With emphasis on the uncertainties of earthquake level, ground condition, soil-pipe interaction and capacity to resist pipe deformation in longitudinal direction, the check point method is applied to the reliability study of water pipeline, and a case study is presented to show the implementation of the proposed model.

scholarly journals Structural Seismic Damage Assessment Method Based on Structural Dynamic Characteristics

2022 ◽  
Author(s):  
Mingzhen Wang ◽  
Lin Gao ◽  
Zailin Yang
Keyword(s):  
Damage Assessment ◽  
Seismic Damage ◽  
Assessment Method ◽  
Frame Structure ◽  
Fundamental Period ◽  
Deformation Pattern ◽  
Seismic Action ◽  
Building Structure ◽  
Structural Dynamic ◽  
Seismic Damage Assessment

Abstract The seismic damage state of building structure can be evaluated by observing the fundamental period change of structure. Firstly, the fundamental period calculation formula that adapts to the deformation pattern and distribution mode of horizontal seismic action for reinforced concrete frame structure is derived. Secondly, the seismic damage assessment standard of building structure considering period variation is established. Then, the seismic damage assessment method of building structure is constructed. Finally, the seismic damage example is used to verify the established evaluation method. The results show that the established research method has high accuracy and good engineering practicability.

scholarly journals Chloride Distribution and Steel Corrosion in a Concrete Bridge after Long-Term Exposure to Natural Marine Environment

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3900 ◽  
Author(s):  
Jun Liu ◽  
Zhilu Jiang ◽  
Yulong Zhao ◽  
Hao Zhou ◽  
Xiaodong Wang ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Marine Environment ◽  
Chloride Transport ◽  
Steel Corrosion ◽  
Concrete Bridge ◽  
Reinforced Concrete Structure ◽  
X Ray Diffraction ◽  
Tidal Zone ◽  
X Ray

Chloride-induced steel corrosion is the most concerning issue for the durability of concrete structures. Concrete and steel samples were obtained from a 30-year-old reinforced concrete bridge. The chloride content was measured by a potentiometric titration method and the microstructure of concrete was obtained by scanning electron microscopy and mercury intrusion porosimetry. The rust phases of the steel were detected by X-ray diffraction and Raman analysis. It was found that the convection depth for chloride transport in cracked concrete was significantly larger than that in uncracked concrete. The concrete in a pier column facing upstream had greater porosity due to the water impact and calcium leaching. The coefficients of variability of chloride diffusivity of concrete for the bridge deck and the pier column were significantly different. Rust phases including lepidocrocite, goethite, akaganeite, magnetite, and maghemite were detected using Raman spectroscopy and X-ray diffraction. The major phases of steel rust in the atmospheric zone were lepidocrocite and goethite, while they were lepidocrocite and maghemite in the tidal zone. The results of this study would provide information concerning the chloride-induced steel corrosion under a marine environment in order to predict long-term behaviors of a reinforced concrete structure.

Development of a Seismic-Performance Assessment Method and Retrofitting Technology Against the Liquefaction of Existing Bridges

2019 ◽  
Vol 14 (2) ◽  
pp. 269-278 ◽  
Author(s):  
Michio Ohsumi ◽  
◽  
Toshiaki Nanazawa ◽  
Shunsuke Tanimoto ◽  
Mitsuhiko Nakata
Keyword(s):  
Performance Assessment ◽  
Seismic Performance ◽  
Assessment Method ◽  
Shaking Table ◽  
Seismic Performance Assessment ◽  
Bridge Foundations ◽  
The Past ◽  
Existing Bridges ◽  
Bridge Foundation

In the past, earthquakes have caused critical damage to bridges built on liquefiable ground, resulting in their collapse or long-term closures. In particular, for existing bridges designed in an age when the liquefaction influence was not considered, appropriate measures should be taken as necessary. However, there are many existing stocks of bridges, which require expensive foundation reinforcement. Therefore, it is crucial to appropriately choose bridge foundations for which anti-seismic measures are a high priority and implement the measures efficiently and successively. The present study aims to develop a seismic-performance assessment method and retrofitting technology for coping with liquefiable ground. For this purpose, a large shaking-table experiment was conducted to determine the effects of the liquefiable ground on bridge-foundation behavior and verify the effect of the retrofitting technology. Based on disaster-case analyses and the results of the shaking-table experiment, a seismic-performance assessment method applicable to practical designing was proposed.

Damage Assessment of Single-Layer Cylindrical Latticed Shells Based on Degradation of Static Stability Capacity

2010 ◽  
Vol 163-167 ◽  
pp. 227-232
Author(s):  
Da Bin Yang ◽  
Yi Gang Zhang ◽  
Jin Zhi Wu ◽  
Hai Tao Zhou ◽  
Wen Chao Liu
Keyword(s):  
Damage Assessment ◽  
Static Load ◽  
Mechanical Performance ◽  
Single Layer ◽  
Static Stability ◽  
Seismic Damage ◽  
Assessment Method ◽  
Live Load ◽  
Dead Load ◽  
Main Index

The static stability capacity is the main index to measure the whole mechanical performance of single-layer latticed shells. Three single-layer cylindrical latticed shells with different height to span ratio were modeled, and their seismic damage were assessed by the degradation of static stability capacity incurred by earthquakes. Two different static load patterns were considered: dead load and the combination of dead load and half span live load. The results show that the damage assessment method is applicable to single-layer cylindrical latticed shells, and the static load patterns have no big influence on the damage assessment of the single-layer cylindrical latticed shells.

scholarly journals Embankment seismic fragility assessment: A case study on Xi’an-Baoji expressway (China)

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246407
Author(s):  
Fa Che ◽  
Chao Yin ◽  
Xingkui Zhao ◽  
Zhinan Hu ◽  
Lu Sheng ◽  
...  
Keyword(s):  
Fragility Curves ◽  
Retaining Wall ◽  
Seismic Damage ◽  
Damage Parameter ◽  
Seismic Fragility ◽  
Response Analysis ◽  
Rc Structures ◽  
Fill Soil ◽  
Soil Foundation ◽  
Wall System

Although embankment seismic damages are very complex, there has been little seismic fragility research yet. Researches on seismic fragility of bridges, dams and reinforced concrete (RC) structures have achieved fruitful results, which can provide references for embankment seismic fragility assessment. Meanwhile, the influencing degrees of retaining structures, such as retaining walls on the embankment seismic performances are still unclear. The K1025+470 embankment of the Xi’an-Baoji expressway was selected as the research object, and the finite difference models of the embankment fill-soil foundation system and embankment fill-soil foundation-retaining wall system were established. The ground-motion records for Incremental Dynamic Analysis (IDA) were selected and the dynamic response analysis were conducted. Probabilistic Seismic Demand Analysis (PSDA) was used to deal with the IDA results and the seismic fragility curves were generated. Based on the assessment results, the influences of the retaining wall on the embankment seismic fragility were further verified. The research results show that regardless of which seismic damage parameter is considered or the presence or absence of the retaining wall, larger PGAs always correspond to higher probabilities of each seismic damage grade. Seismic damages to the embankment fill-soil foundation-retaining wall system are always lower than those of the embankment fill-soil foundation system under the same PGA actions, thus, the retaining wall can decrease the embankment seismic fragility significantly.

Sign in / Sign up

Export Citation Format

Share Document