Issue 62

Y. Boulmaali-Hacene Chaouche et alii, Frattura ed Integrità Strutturale, 61 (2022) 61-106; DOI: 10.3221/IGF-ESIS.62.07

contacting surfaces of the steel tube and the concrete core (inner surface of the steel tube and outer surface of the concrete cylinder), we have defined it by a tangential contact materialized by a friction coefficient equal to 0.2 (Fig. 6a). For the Finite Element model, the lower rigid plate, in contact with the bottom of the steel tube, is fixed in all six directions (Ux=Uy=Uz=0,    x y z θ θ θ 0 ) and the upper rigid plate is fixed in all five directions except the vertical displacement direction ( Ux=Uy= 0,    x y z θ θ θ 0 ). The models are subjected to axial center compression loading represented by an imposed displacement applied to the upper rigid plate (imposed displacement Uz= 10mm) (Fig. 6b).

(a) (c) Figure 5: Mesh of columns filled with rigid plates at the ends: (a) Concrete, (b) Steel tube, (c) Tube filled with concrete. (b)

(a) (b) Figure 6: Interaction loading and limit conditions of the models (a) Loading and boundary conditions, (b) interaction contact.

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