الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Modeling the mechanical behavior of reinforced concrete is still one of the most difficult
challenges in the field of structural engineering. Concrete is a quasi-brittle material, its
response under loading cannot be modeled as brittle behavior due to the presence of the large
fracture zone, and on the other hand, it cannot be modeled using the classical mechanics of
material techniques, such as plasticity theories, as they cannot handle materials with severe
discontinuities such as cracks. The fundamental characteristics of concrete behavior have been
established through experimental testing of plain concrete specimens subjected to specific,
relatively simple load histories which revealed the highly nonlinear response of concrete
especially close to and beyond the peak load. In order to describe the complex behavior of
concrete, a large variety of constitutive models have been proposed to characterize the stress-
strain relation and failure behavior of concrete. The presence of numerous models for
describing concrete behavior reflects the difficulties encountered in formulating and
interpreting such a behavior. The main objective of this research is to investigate the
macroscopic behavior and progressive failure of reinforced concrete structures under static
loading using the finite element techniques. The benefits and limitations of using these
techniques for modeling the behavior of reinforced concrete have been studied. In addition, a
comprehensive assessment of the reliability of numerical nonlinear analysis as a versatile tool
for understanding the behavior of reinforced concrete beams under static loading have been
addressed. The significance of this research lies in creating a road map for researchers using
finite element codes such as ABAQUS in studying concrete behavior, showing the different
stages for formulating each model accurately, the restrictions and limitations of each model,
the accuracy of these models in interpreting concrete material behavior, and the difference
between these models and their results when compared to the experimental results available in
the literature. A comprehensive review of the input parameters of each model, and their
influence on the obtained solution have been emphasized in order to achieve the goals of this
study and guide researchers to build the most accurate and reliable model for each case study.
In order to achieve the objectives outlined in this thesis, a calibration process have been
conducted to verify the ability of the tested concrete models to describe concrete response
under static loading, in addition a classification of the key parameters governing the
construction of a sound and accurate model have been outlined. Furthermore, a detailed
description for the modeling of three different reinforced concrete beams as case studies has
been introduced. The first case study has been chosen to validate the three models offered by
ABAQUS to study concrete behavior. The behavior of this case study was modeled using the
different ABAQUS concrete models and a comparison has been conducted between the
outputs of ABAQUS models, in order to demonstrate the drawbacks and limitations of each
model. In addition, the findings of this comparative study have been used as a guide to
construct the other two case studies by applying the most suitable model. The results of the
applied model (Concrete Damaged Plasticity Model) are in good agreement with the
experimentally documented results in the literature. The results of the model can be used in
validating and guiding experimental work, in addition to exploring concrete response under
complicated loading conditions such as the behavior of reinforced concrete deep beams with
and without web opening, which have been studied under monotonic loading in comparison
with the ACI 3\8-08 (Appendix A) and the Egyptian Code (203 - 2006) provisions.