Carbon fiber reinforced polymer strengthened reinforced concrete square columns under pre-existing eccentric loads

Kian N., Farzam M., Rezaie Oshtolagh M.

ADVANCES IN STRUCTURAL ENGINEERING, cilt.24, sa.15, ss.3420-3432, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 24 Sayı: 15
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1177/13694332211029730
  • Dergi Adı: ADVANCES IN STRUCTURAL ENGINEERING
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Aquatic Science & Fisheries Abstracts (ASFA), Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.3420-3432
  • Anahtar Kelimeler: Pre-existing load condition, CFRP layer, strengthening, RC Column, tension-controlled region, AXIAL-FLEXURAL INTERACTION, FRP-CONFINED CONCRETE, STRESS-STRAIN MODEL, RC COLUMNS, CFRP COMPOSITES, BEHAVIOR, PERFORMANCE
  • İstanbul Teknik Üniversitesi Adresli: Hayır

Özet

Numerous experimental studies have been conducted on the behavior of strengthened columns, mostly with glued layers of FRP before load application, and rarely under the pre-existing load. Results confirm a good efficiency of strengthening in the compression-controlled region of the columns, as mentioned in design codes and guides such as ACI 440.2R-17. However, their behavior in the tension-controlled region is still a challenging subject. Moreover, when the eccentricity is large enough, the efficiency of the strengthening method needs more attention. This study aimed at strengthening six RC columns in the tension-controlled region under the pre-existing load condition. Furthermore, tested specimens were verified using a nonlinear finite element analysis performed in ATENA software. Moreover, some identical strengthened specimens, which were not subjected to pre-existing load during strengthening, were modeled to capture the effect of pre-existing loads. The results of the analyses were in good agreement with experimental data. Comparison of numerical results obtained for columns strengthened without pre-existing load, and under pre-existing load showed that pre-existing loading significantly reduced the efficiency of FRP jacketing. Also, assuming a linear variation of confinement pressure in the tension-controlled region of the interaction diagram results in good agreement with attained results.