Behavior of slender steel concrete composite columns in eccentric loading

Abstract

Ten slender steel reinforced cencrete (SRC) composite columns are tested under eccentric loading conditions. Effects of concrete strength, slenderness of columns and eccentricity of the axial load are studied. The load-carrying capacity is reduced with increased slenderness ratio and eccentricity. Concrete strength has no obvious influence on eccentrically loaded columns. Then, a nonlinear numerical method of pin-ended slender columns is also presented. This method is applicable for determining the material failure load or buckling failure load of a slender steel reinforced concrete composite column. In this method both material and geometric nonlinearities are taken into account. The results of numerical analysis accord well with the test results. The test results are also compared with the results predicted by ACI318-05 and the China Specifications.

Nonlinear analysis of reinforced and composite columns in fire

“…It is obvious that the results obtained by the IDEA StatiCa solver and the data stated in reference [9] are closely similar. Figure 19: Normal force-horizontal displacement diagrams according to [9] vs. IDEA StatiCa, SRC-E2 column.…”

“…Forth example is concrete-encased composite column according to [9], where the behavior of concrete-encased composite columns under eccentric loading is examined experimentally and also by numerical analysis. The column is loaded by eccentric force F, with the eccentricity e (along the major axis), which is the same at the top and the bottom of the column.…”

“…The column is loaded by eccentric force F, with the eccentricity e (along the major axis), which is the same at the top and the bottom of the column. Here, we assume the specimens denoted as SRC-E2 and SRC-E8 in the original paper [9]. For these columns, the following geometrical parameters are given: column length L = 3200 mm, e = 30 mm (SRC-E2); e = 150 mm (SRC-E8), the other parameters are stated in Fig.…”

“…The values of ultimate resistance F max and corresponding horizontal displacement w Fmax at mid-length of the column obtained by the IDEA StatiCa solver are compared with the data stated in reference[9], see Tab. 4.…”

Confinement detailing of concrete encased steel concrete composite columns

“…When an axial load is applied to a column, it induces two effects: one is the compressive membrane effect that reduces the lateral column deflection, and the other one is the P-Δ effect that amplifies the lateral column deflection. When the axial load ratio is small, the compressive membrane effect is more dominant and vice versa [20]. The steel section is known to be ductile and provides more ductility to the composite section.…”