الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
When analyzing reinforced concrete slabs using the finite element method, shell elements may be used in modeling the slab. In some cases, the traditional modeling of slabs using shell elements fails to represent the real structure configuration the aim was to get a general method to represent slabs having drops or changes in thickness.A special eight-node brick element was developed and applied to represent the concrete slab. The element includes 32 Gaussian integration points rather than 8 integration points as in the ordinary eight-node brick element. Thus, the element is capable of representing the change in material properties. To overcome the element stiff behavior in bending, up to nine additional incompatible bending modes may be introduced to the element’s original formulation. When analyzing slabs subjected to lateral loads.It was found that only two of the nine incompatible bending modes are required to represent the slab bending behavior, which was adopted in the present work.A computer program was built using the developed element to represent the concrete.Also a bar element and a contact elemente were used to represent the steel reinforcement and the interaction between the steel and concrete. The nonlinear behavior of the materials was activated using selected constitutive models. A tri-axial stress state model for concrete was used; also, the tension stiffening effect was taken into account. An elastic-perfect plastic model was used for the steel reinforcement and the contact element.The program was verified in both the linear and nonlinear ranges using valid results from other analytical methods and some well-known experiments. Good agreement was found between the results.The program was applied to perform a parametric study for slabs having dropped part with different configuration. The slab behavior was studied during loading at the different stages. The conclusions of the study and recommendations for future work are given.