Study of constitutive models of DIANA FEA for long-term analysis of pre- stressed beams with bonded tendons

Resumo

The work presented here was motivated by the existence of several constitutive models capable of
numerically representing the time effect on prestressed beams. The main goal of this study is to analyze different
models, comparing their influence on the long-term behavior in prestressed concrete beams. The study compares
the behavior of prefabricated concrete beams with bonded post-tensioning using different constitutive models for
concrete and steel tendons. The simulation was carried out using DIANA FEA. Some of the models adopted are
from design codes, and others from models and theories available in literature. The study proposes a parametric
study among the different models as well as the effect of the input parameters on the overall behavior of the
structure. The nonlinear behavior of cracked concrete and the steel yield behavior in addition to the creep behavior
of the concrete were considered. The results were compared with experimental results of prestressed beams tested
for creep analysis for a long period of time. The results pointed out to the importance of choosing the appropriate
constitutive model in simulations of prestressed elements.