Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
285310 | Journal of Constructional Steel Research | 2012 | 11 Pages |
The paper describes 36 experimental tests conducted on rectangular and square tubular columns filled with normal and high strength concrete and subjected to a non-constant bending moment distribution with respect to the weak axis. The test parameters were the nominal strength of concrete (30 and 90 MPa), the cross-section aspect ratio (square or rectangular), the thickness (4 or 5 mm) and the ratio of the top and bottom first order eccentricities etop/ebottom (1, 0.5, 0 and − 0.5). The ultimate load of each test was compared with the design loads from Eurocode 4, presenting unsafe results inside a 10% safety margin. The tests show that the use of high strength concrete is more useful for the cases of non-constant bending moment, whereas if the aim is to obtain a more ductile behavior the use of concrete-filled columns is more appealing in the cases of normal strength concrete with non-constant bending moments because, although they resist less axial force than the members with HSC, they obtain a softened post-peak behavior.
►36 tests of rectangular CFT columns under axial load and non-constant flexure ►The use of HSC is more useful with regards to the HSS for variable bending moment. ►The ductility is more dependent from strength of concrete than on the eccentricity.