Strengthening of RC Bridges
During past seismic events several cases of concrete bridges with poor structural behaviour and severe damage were reported. In this chapter, common damage patterns in RC bridges are illustrated, with reference to several previous studies about the seismic performance of bridge components. The focus of the chapter is on pier behaviour, wherein damage is usually more significant and quite often there is a need to retrofit these elements. In this context, the main objective of this chapter is to present the most common retrofitting strategies for RC bridges and the resulting benefits to their structural behaviour. Several types of piers are considered, where the cross section ranges from solid to hollow and from circular to rectangular. One of the most common retrofit measures for RC bridge piers is the full or partial jacket, which can be made in FRP, steel or RC. Experimental and numerical tests were carried out to assess the benefits to bridge pier behaviour, resulting from shear strengthening of piers with hollow cross section. Moreover, analytical studies are presented on the performance of bridges retrofitted using different techniques, aiming at strengthening and/or confinement, and a method for assessing the seismic fragility of retrofitted bridges is described, along with an application to a bridge with circular piers.
KeywordsBridge damage Retrofit strategies Piers jacketing Experimental and analytical studies
Part of this work reports to research financially supported by Project POCI-01-0145-FEDER-007457—CONSTRUCT—Institute of R&D in Structures and Construction, funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds through Fundação para a Ciência e a Tecnologia (FCT).
- 4.Santarosa D, Campos Filho A, Beber A, Camplagnolo J. Concrete columns confined with CFRP sheets. In: JG T, editor. International conference on FRP composites in civil engineering. Hong Kong, China; 2001.Google Scholar
- 5.Teng J, Chen J, Smith S, Lam L. FRP strengthened RC structures. New York: Wiley; 2001.Google Scholar
- 10.Pavese A, Bolognini D, Peloso S. FRP seismic retrofit of RC square hollow section bridge piers. J Earthq Eng. 2004;8:225–50.Google Scholar
- 14.Delgado P, Arêde A, Vila Pouca N, Rocha P, Costa A, Delgado R. Retrofit of RC hollow piers with CFRP sheets. Compos Struct. 2012;94(4):1280–7.Google Scholar
- 16.Oliveira CS, Azevedo J, Delgado R, Costa AG, Costa AC. O Sismo de Northridge, Los Angeles, 17 de Janeiro de 1994—Ensinamentos para Portugal. Edição Conjunta dos IC-IST/IC-FEUP: Lisboa; 1995 (in Portuguese).Google Scholar
- 17.EASY. Earthquake Engineering Slide Information System; 1997. http://www.ikpir.fgg.uni-lj.si/easy/.
- 18.NISEE. National Information Service for Earthquake Engineering, University of California, Berkeley; 2006. http://nisee.berkeley.edu/taiwan/.
- 19.EERI. Learning from Earthquakes: The Wenchuan, Sichuan Province, China, Earthquake of May 12, 2008, EERI—Special Earthquake Report—October, 2008.Google Scholar
- 20.ISSN. General introduction of engineering damage of Wenchuan Ms 8.0 earthquake. J Earthq Eng Vib; 2008.Google Scholar
- 23.Delgado P, Sousa F, Rocha P, Arêde A, Vila Pouca N, Costa A, Delgado R. Experimental and numerical analysis on the cyclic behavior of bridge piers with and without CFRP retrofit. In: 5th ECCOMAS thematic conference on computational methods in structural dynamics and Earthquake engineering. COMPDYN 2015.Google Scholar
- 25.Seismosoft. SeismoStruct. computer program for static and dynamic nonlinear analysis of framed structures. http://www.seismosoft.com.
- 27.Federal Highway Administration (USA): Seismic retrofitting manual for highway structures: part 1—Bridges. Publication no. FHWA-HRT-06-032, McLean, VA; 2006.Google Scholar
- 29.Padgett JE, DesRoches R. Methodology for the development of analytical fragility curves for retrofitted bridges. Earthq Eng Struct Dyn. 2008;37(8):1157–74.Google Scholar
- 30.Stefanidou SP, Kappos AJ. Methodology for the development of bridge-specific fragility curves. Earthq Eng Struct Dyn. 2017;46(1):73–93.Google Scholar
- 31.Stefanidou SP, Kappos AJ. Efficiency of different retrofit measures in reducing seismic fragility of bridges. In: 16th European Bridge conference, Edinburgh, June 2015, Paper no. 1477.Google Scholar
- 33.Stefanidou SP. Structure-specific Fragility Curves for As-Built and Retrofitted Bridges. Ph.D. thesis, Civil Engineering Department, Aristotle University of Thessaloniki, Greece; 2016.Google Scholar