Nueva fórmula de la excentricidad para introducir la fluencia en piezas comprimidas esbeltas de hormigón

New eccentricity formula for considering creep in concrete slender compressed members

The paper contains the development, in a analitycal way, and the final proposal of a new formula (in terms of a delayed eccentricity), alternative to the similar one normally used till now (included in the CEB Model Code), for taking into account the creep effects in concrete slender compressed members; calculations are also made on the basis of Dischinger model, but taking a enought general actions set (including a pure geometrical component) on the member. This development shows some theoretical problems related to the old formula, that is unsafe in practice, as checked through a simple comparative example; so, this formula seems to be not suitable. Validity limits, needed for this kind of formulae (in spite of CEB Model Code shows no restriction on it) are also defined, being linked to symmetry situations of thers near to that.