A numerical analysis using the finite element method has been made in this dissertation to study the local buckling behavior of thin-walled high strength reinforced concrete box piers. An incremental elastic-plastic model based on the classical plasticity theory is used for the concrete. This model decomposes the strain rate into elastic and inelastic strain rates, and considers aspects such as elasticity, yield, and hardening. The smeared cracking method is used to perform constitutive calculations independently at each integration point of the finite element model. Tension stiffening is used to model the tension characteristics of concrete, including the post-cracking behavior. The reinforcement is modeled by the standard metal plasticity approach, and is superposed on a mesh of elements used to model the plain concrete. The numerical analysis for the pier models is implemented through a general-purpose finite element program ABAQUS. Twenty-node, reduced integration, quadratic brick elements and eight-node, reduced integration, quadrilateral shell elements are used, and the computation is performed by incremental loading and the modified Riks algorithm.; The validity of the material model and the finite element method is verified by comparison of the numerical results with available experimental results. Based on this comparison, it is concluded that the numerical analysis being carried out can be used with confidence to study local buckling of thin-walled high strength reinforced concrete box piers.; Finally, the behavior of the box piers is further investigated by making a parametric study involving various concrete strengths, wall slenderness ratios, and pier heights. The sensitivity of the models to the separate effects of these parameters and various combinations of them is demonstrated by means of curves for the buckling and post buckling capacities of the piers.
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