Analytical model for predicting axial capacity and behavior of concrete encased steel composite stub columns

Numerical Investigation on Load-carrying Capacity of High-strength Concrete-encased Steel Angle Columns

“…e co;u ) because concrete cover restrains local buckling of steel angles (Chen and Lin 2006), and local bucking of steel angles was assumed to incorporate spalling of concrete cover at corners (i.e., f c;u ¼ 0 if e s ! e bs ) (case 2 in Fig.…”

“…In the figure, e yl , e hl , e ul , f yl , f hl , f ul are yield, hardening, and ultimate strains, and their corresponding stresses, respectively (assuming e hs ¼ 10e ys and e us = 0.15 for mild steel (Zubydan and ElSabbagh 2001)). Local buckling of longitudinal bars was assumed to initiate when the strain of longitudinal bars reaches the peak strain of concrete cover (i.e., e bl ¼ e co;u ) (Gomes and Appleton 1997;Chen and Lin 2006), and post-local buckling behavior was modeled by the plastic mechanism approach (or yield-line analysis, Eq. (8)) (Morino et al 1986;Gomes and Appleton 1997).…”

Numerical simulation of concrete encased steel composite columns

“…2. Chen and Lin [18] effectively used the same approach [22,23] in their analytical study, which was conducted using different steel section shapes and different reinforcement layouts, and evaluated the confinement factors for the highly and partially confined concrete zones. The confinement zones can be simplified, as adopted by Mirza and Skrabek [4], by adjusting the parabolic zones into rectangular zones.…”

“…The approximate value of (f l ) can be obtained knowing the confinement factors for the highly and partially confined concrete zones as given by Chen and Lin [18]. The confinement factor for highly confined concrete varied from 1.1 to 1.97 depending on the spacing between transverse reinforcement and structural steel shape.…”

Simulation of partially encased composite steel–concrete columns with steel columns

“…According to EC4 [1] and other related articles [3,[5][6][7][8]12], the compression resistance of a composite steel-concrete crosssection is equal to the sum of the plastic resistances of the steel cross-section, the reinforcement, and the concrete. The corresponding resistance of the fictitious cross-section, as for any purely steel section, is simply the product of the design stress with the total area, i.e.…”