Development of strength reduction factors for performance-based seismic design of bridges in far-fault seismic regions

Rabaia T., DİCLELİ M.

Engineering Structures, cilt.318, 2024 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 318
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1016/j.engstruct.2024.118805
  • Dergi Adı: Engineering Structures
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Aquatic Science & Fisheries Abstracts (ASFA), Communication Abstracts, Compendex, Geobase, ICONDA Bibliographic, INSPEC, Metadex, DIALNET, Civil Engineering Abstracts
  • Anahtar Kelimeler: Bridges, Far-fault ground motions, Performance-based design, Seismic design, Strength reduction factor
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

In this paper, strength reduction factors (R-factors) for performance-based seismic design of bridges in far-fault seismic regions are developed. Response spectrum analyses (RSA) and nonlinear time history analyses (NTHA) of simplified bridge models with piers of circular and rectangular sections having several substructure-superstructure connections are performed for wide ranges of design parameters and pier displacement ductilities based on target performance levels are obtained. Subsequently, a set of equations representing R-factors is proposed by performing linear regression analyses on the data obtained from the analyses. The accuracy of the proposed equations is investigated by performing error performance analyses, which indicated R-factors with mean error values close to zero. Furthermore, a simple application procedure of the proposed R-factor equations is presented and explained in detail through various sample bridges designed to achieve the performance objectives recommended by AASHTO LRFD, Eurocode, and the Canadian Highway Bridge Design Code (CSA). Eventually, a comparison between the estimated R-factors and those suggested by design codes is presented. The results showed that AASHTO LRFD recommends conservative R values for single-column bents, while it provides overestimated R values for multiple-column bents. Indeed, it is found that Eurocode recommends conservative R values for piers of limited-ductile behavior and relatively high R values for piers of ductile behavior. Therefore, it is concluded that the R-factors suggested by design codes might result in performance levels not intended in design.