FE analysis of short- and long-term behavior of simply supported slender prestressed concrete columns under eccentric end axial loads causing uniaxial bending

• A computational model for slender prestressed columns is developed.
• The interaction between P-delta and time-dependent effects is considered.
• Short- and long-term behavior of slender columns is examined.

An eccentrically loaded slender prestressed concrete column is characterized by P-delta effects resulting from the development of lateral deflections with the applied axial loads. When long-term sustained loads are applied, P-delta effects would interact with time-dependent effects resulting from creep and shrinkage of concrete and relaxation of prestressing steel. This paper presents a computational model for predicting the short-term full-range and long-term service-load behavior of slender prestressed concrete columns under uniaxial eccentric loads. The P-delta interactions with material nonlinearity and with time-dependent effects are considered. The model is developed based on the Euler–Bernoulli theory. The proposed analysis is validated against the experimental data and other numerical solution available in literature. Typical aspects of short- and long-term behavior of slender prestressed concrete columns are evaluated. The study shows that the performance of a reinforced concrete slender column can be effectively improved by prestressing and that the time-dependent effects for slender prestressed concrete columns are quite important. It is also indicated that the imperfect tendon placement has a limited effect on the short-term behavior but has a significant influence on the long-term behavior.