Innovative Seismic Retrofitting of Bridge: A Perspective Study
explanatory Essay
1322 words
Introduction Many existing bridges structure has been designed without seismic provisions are vulnerable which has demonstrated by recent earthquake. The consequent of the extensive damage to bridge structure include potential loss of life and property, and interruption of transportation system that can contribute to major economic and impact to the society. Concern about the vulnerability of bridges being damage, there are significant need to perform adequate seismic retrofit technique prior to future seismic event. Furthermore, for ensuring the existing bridge meet current safety seismic design requirement consist of detailing schemes that can offer flexural ductility, high-energy dissipation and preventing shear failure. Thus, this paper only focuses on retrofitting of bridge column/pier. Therefore, it is very important to identify potential deficiencies and examine the strategies for retrofit these bridge pier in the rehabilitation of existing bridge pier, which can upgrade the performance and extension of its service life. Common deficiencies for reinforced concrete column and piers as shown in Figure 1. Research Significance Research that had been investigated the seismic performance in area of innovative materials have been significantly shown potential and promise better in civil engineering application and solution in future. Thus, the objective this paper provides relevant an innovative seismic retrofit technique for bridges pier using innovative material include shape memory alloy (SMA) and fiber reinforced polymer (FRP) and has develop as alternative improvement to the existing bridge pier. For emphasizing each method of retrofit, comparative drawbacks and advantages on seismic performance are include in the scope of... ... middle of paper ... ...pirals.” Doctor of Philosophy in Civil Engineering, University of Illinois Yu-Fei Wu, Tao Liu, and Leiming Wang (2008). “Experimental Investigation on Seismic Retrofitting of Square RC Columns by Carbon FRP Sheet Confinement Combined with Transverse Short Glass FRP Bars in Bored Holes.” J. Compos. Constr.,ASCE.12, 53-60. Liang Chang, A.M.ASCE1; Fan Peng2; Yanfeng Ouyang, A.M.ASCE3; Amr S. Elnashai, F.ASCE4; and Billie F. Spencer Jr., F.ASCE5 DOI: 10.1061/(ASCE)IS .1943-555X.0000082. © 2012 American Society of Civil Engineers. William f. Cofer, David I. McLean and Yi Zhang, “Analytical Evaluation on Retrofit Strategies for Multi-Column Bridges”, Technical Report for research project T9902-11 Riyad Aboutaha, Fares Jnaid, Sara Sotoud, and Mucip Tapan “Seismic Evaluation and Retrofit of Deteriorated Concrete Bridge Components” Technical Report 49111-23-22 june 2013
In this essay, the author
- Explains that many existing bridges structure has been designed without seismic provisions are vulnerable which has demonstrated by recent earthquake. the paper focuses on retrofitting of bridge column/pier.
- Explains the purpose of this paper, which is to provide relevant an innovative seismic retrofit technique for bridges pier using innovative materials such as shape memory alloy and fiber reinforced polymer.
- Explains that a general screening process and prioritization study of bridges are performed to determine which ones need seismic retrofitting.
- Explains how a detailed methodology is applied for identifying the structure analysis of bridge as having high risk in prioritization and determining the overall alternative retrofitting includes cost and ease of installation.
- Explains that seismic retrofit strategies can be applied one or more approaches together to achieve an improvement level of performance such as strengthening, partial replacement, and displacement capacity enhancement.
- Explains that the vulnerability of bridge structure may be due to weakness in structural system and non-ductile detailing which could be serious damaged for seismic event.
- Explains that seismic vulnerability assessment was trigged in 1971 when san fernando earthquake caused notable damage to the bridge. evaluation of seismic retrofitting was developed and revised many times to avoid severe damage or collapse.
- Explains that the common failure mechanisms of bridge columns are shear failure, flexural capacity and inadequate reinforcing embedment and laps.
- Cites andrawes b, shin m, and wierschem n. active confinement of reinforced concrete bridge columns using shape memory alloys.
- Explains that william f. cofer, david i. mclean, and yi zhang, "analytical evaluation on retrofit strategies for multi-column bridges", technical report t9902-11.
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