الفهرس 
INTRODUCTION..Only 14 pages are availabe for public view
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Abstract
• The maIn objective of the thesis is to develop an incremental variational inequality model to simulate the elasto-plastic dynamic contact problems. Structural damping effects are taken into account.
• Strong formulation and its equivalent variational inequality principle are reported thoroughly for that highly nonlinear class of problems.
• Finite element method is exploited as a discretization engine for spatial domain where central difference method is used to descritize the time domain.
• The incremental convex programming method is enhanced to solve the constrained minimization problem, which depicts the physical system at each increment of time.
• The model is an adaptive one, since the increment of time, relevant to a specific state is determined directly according to the instant of the following change of one of the contact boundary conditions or the change of material response of one of the finite elements.
• The solution procedure is equipped by a set of updating mechanisms developed to reflect the temporal changes of contact boundary conditions and constitutive relationship through time marching.
• Special attention is given for the systems subjected to impulsive and impact load.
• The model is capable to determine and simulate the bounding and rebounding phases for problems of impacting a half space, as a target, with an elastic impactor.
• Rayleigh damping model IS adopted, however, any other recommending model can be used in the framework of the proposed model.
• Several problems of different natures are solved and the results compared favorably with those published in the literature.
• An investigation to study the effect of several parameters, such as relative densities, relative modulus of elasticity and initial velocity of the impactor is worked out.
• To consider the effect of structural damping, the author is looking forward to adopt a more accurate and realistic model of damping rather than the simple Ralyeigh model.
• The model can be extended to accommodate the effects of surface friction, thermoelasticity, and large deformation, as additional source of nonlinearities.