The current study examines experimentally the interface behaviour of retrofitted columns subjected to pseudoseismic axial loading. It includes 12 specimens of square section (150x150x500 mm) of 24.37 MPa nominal concrete strength with 4 longitudinal steel bars of 8 mm (500 MPa nominal strength) with transverse reinforcement ratio ωc=0.15. All columns were retrofitted with reinforced concrete jackets (RC) of 80 mm width of approximate 30 MPa concrete strength including 4 longitudinal bars (500 MPa nominal strength) and different confinement ratios along with two kinds of interface reinforcement: dowels crossing vertically the interface plane and welded bend-down bars. Interface treatment differs from smooth to roughen with chipping method for comprehension of the shear mechanisms along the contact of the two different-time casted concretes. Results indicate that: A) Interface treatment ended up to expanded peak area approaching ductile behaviour before the development of the descending branch; B) the presence of the welded bend-down bars increase the initial cord stiffness of the upgraded element but due to buckling phenomena the secant stiffness is reduced.
The current study examines experimentally the interface behaviour of retrofitted columns subjected to pseudoseismic axial loading. It includes 12 specimens of square section (150x150x500 mm) of 24.37 MPa nominal concrete strength with 4 longitudinal steel bars of 8 mm (500 MPa nominal strength) with transverse reinforcement ratio ωc=0.15. All columns were retrofitted with reinforced concrete jackets (RC) of 80 mm width of approximate 30 MPa concrete strength including 4 longitudinal bars (500 MPa nominal strength) and different confinement ratios along with two kinds of interface reinforcement: dowels crossing vertically the interface plane and welded bend-down bars. Interface treatment differs from smooth to roughen with chipping method for comprehension of the shear mechanisms along the contact of the two different-time casted concretes. Results indicate that: A) Interface treatment ended up to expanded peak area approaching ductile behaviour before the development of the descending branch; B) the presence of the welded bend-down bars increase the initial cord stiffness of the upgraded element but due to buckling phenomena the secant stiffness is reduced.
Interface behaviour of retrofitted columns subjected to axial repeated loading / Achillopoulou, Dimitra; Athanasios, Karabinis2. - ELETTRONICO. - (2014). ( 2 nd European Conference on Earthquake Engineering and Seismology Instabul 08/2014).
Interface behaviour of retrofitted columns subjected to axial repeated loading
ACHILLOPOULOU, DIMITRA;
2014
Abstract
The current study examines experimentally the interface behaviour of retrofitted columns subjected to pseudoseismic axial loading. It includes 12 specimens of square section (150x150x500 mm) of 24.37 MPa nominal concrete strength with 4 longitudinal steel bars of 8 mm (500 MPa nominal strength) with transverse reinforcement ratio ωc=0.15. All columns were retrofitted with reinforced concrete jackets (RC) of 80 mm width of approximate 30 MPa concrete strength including 4 longitudinal bars (500 MPa nominal strength) and different confinement ratios along with two kinds of interface reinforcement: dowels crossing vertically the interface plane and welded bend-down bars. Interface treatment differs from smooth to roughen with chipping method for comprehension of the shear mechanisms along the contact of the two different-time casted concretes. Results indicate that: A) Interface treatment ended up to expanded peak area approaching ductile behaviour before the development of the descending branch; B) the presence of the welded bend-down bars increase the initial cord stiffness of the upgraded element but due to buckling phenomena the secant stiffness is reduced.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
