Abstract

    The reinforced concrete columns are, in general, subject to a law of non-uniform 
bending moment due to the existence of unequal end eccentricities. In addition, the use 
of high-strength concrete in the construction of ordinary structures is becoming 
increasingly common, which suppose the design of more slender columns. However, 
the literature review indicated that experimental studies for high-strength concrete 
columns subjected to different end eccentricities are scarce and focus their study on the 
behavior of short-length columns under one way flexural-compression loadings.

    On the other hand, the design codes generally propose simplified methods in order 
to predict the ultimate load of slender columns under compression with unequal end 
eccentricities. However, the simplified methods have been verified, in most, with 
normal strength concrete columns. The extrapolation of these methods to high-strength 
concrete without scientific support and adequate experimental verification may lead to 
unreliable results.

    The behavior of 68 slender columns under compression with different end 
eccentricities and skew angles cast with normal and high-strength concrete has been 
studied on this thesis. These experimental tests are aimed at understanding the behavior 
of this type of structural elements and also should serve to calibrate numerical models 
and to validate simplified methods.

    The research importance focuses on the contribution of increasing the available 
experimental database in order to verify the design methods proposed by the different 
design codes for reinforced concrete columns subjected to this kind of solicitation. In 
addition, a parametric study was conducted to propose an expression for calculating the 
coefficient of equivalence Cm, taking into account the behavior of such structural 
elements, through a numerical finite element method calibrated with the experimental data. The 
proposed expression covers the normal and high-strength concrete slender flexural-
compression columns under unequal eccentricities and skew angle loaded ends.