نوع مقاله : پژوهشی
نویسندگان
1 دانشکده ی مهندسی عمران ، دانشگاه علم و صنعت ایران
2 دانشکده ی مهندسی عمران - دانشگاه علم و صنعت ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The behavior of the reinforced concrete structures is influenced by the bond-slip mechanism between concrete and rebar. The performance and strength of
the structure are strongly affected by this mechanism. Therefore, it is indispensable to take bond-slip effects into account when analyzing reinforced
concrete structures. In the current study, bond-slip behavior between concrete
and reinforcement is investigated and a new bond-slip model for deformed bar is
proposed. The main distinction between the proposed model and the current
models is that in this model, slip starts when bond stress reaches a threshold
value. Constant parameters of the proposed model are maximum bond stress and
maximum slip. Calibration of the constant parameters of the model is done based
on trial and error method with the aim of achieving the best coincidence with
the experimental results. For each of constant parameters of the model, three
different values were selected. So in total, nine models were used in modeling
the interaction between rebar and concrete. To calibrate the model, some
pull-out tests are simulated by finite element software of ABAQUS. In this
simulation in order to take bond-slip effects into consideration, steel nodes
are connected to that of adjacent concrete through non-linear springs. The
behavior of these springs is defined based on a variety of bond-slip models for
deformed bar. Considering the error of models with respect to experimental
values, the best model with the minimum error was chosen. Moreover the best
proposed model was compared with current models. The results showed that the
proposed model has much better predictions than the current methods regarding
both the maximum load and post-peak behavior of load deformation curve.
Furthermore, the proposed model can be expanded for long bonded length and
splitting failure mode by adding a reduction function for take into account
post-yield strain effects.
کلیدواژهها [English]
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