Cyclic behavior of strong beam–weak column joints strengthened with different configurations of CFRP sheets

• Autorzy: Ilia Elaheh , Mostofinejad Davood , Moghaddas Amirreza

Identyfikatory

DOI

10.1007/s43452-020-0015-7

• Języki publikacji: EN

Abstrakty

EN

The current paper reports the results of experiments on deficient exterior reinforced concrete (RC) strong beam–weak column connections strengthened with carbon fiber-reinforced polymer (CFRP) sheets. Five RC-joint specimens with half-scale size were manufactured and tested subjected to constant axial and reversed cyclic quasi-static loads. These joints consisted of one control and four specimens retrofitted with FRP sheets used in different strengthening configuration. The study is mainly directed to the examination of the different anchoring methods for longitudinal FRPs at beam–column intersection including L-shaped anchorage or CFRP anchor fans as a modern anchorage technique. Furthermore, the efficiency of transverse CFRP sheets in the form of innovative corner strip-batten technique to improve the seismic performance of the weak column was compared with longitudinal sheets. The externally bonded reinforcement on grooves (EBROG) method was also used in all strengthening schemes to eliminate surface debonding of CFRP. Test results revealed that although all the retrofitting schemes used led to significant improvements of up to 80% in strength capacity, longitudinal FRP sheets applied through the EBROG method and anchored with CFRP fans were more effective in inducing a completely ductile behavior in the joints, while the plastic hinge was also relocated into the beam.

Słowa kluczowe

EN

strong beam; weak column; L-shaped anchorage; FRP anchor fan; corner strip-batten; EBROG method

PL

belka; wentylator; kotwienie

• Wydawca: Springer ; Wrocław University of Science and Technology
• Czasopismo: Archives of Civil and Mechanical Engineering
• Rocznik: 2020
• Tom: Vol. 20, no. 2
• Strony: 1--26
• Opis fizyczny: Bibliogr. 31 poz., fot., rys., wykr.

Twórcy

autor

Ilia Elaheh

• Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan 84156‑83111, Iran

autor

Mostofinejad Davood

• Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan 84156‑83111, Iran

autor

Moghaddas Amirreza

• Department of Civil Engineering, Isfahan University of Technology (IUT), Isfahan 84156‑83111, Iran

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021)