This dissertation project proposes to investigate the influence of considering construction stages in tall reinforced concrete buildings by evaluating conventional strategies, which do not take the construction stages into account, and strategies that consider them in an approximate way, including a model interpreted as a reference, known as construction effect. Nowadays, with the development of structural analysis and design programs, a change in the structural calculation is observed, moving from conventional models to those that describe the real sequence of loading and construction. Since the structure is subjected to internal forces as it is built, it is desirable for structural engineers to consider the loading being applied progressively and the evolution of the mechanical properties of materials with time. The conventional method, by considering the action of all loads on the completed structure and the modulus of elasticity of concrete at 28 days, does not reflect the reality of constructions. The main distinction between analysis strategies lies in how displacements along the height of the building are treated. In the conventional model, since the loads are applied in a single step, displacements occur simultaneously and cumulatively. On the other hand, in incremental analysis, the loads acting on a given floor do not cause displacements, or consequent internal forces, on an upper floor not yet built. Analysis without consideration of the construction stages may result in an inconsistent distribution of internal forces and may not represent the real behavior of the structure, wich may even result in inadequate design and consequent pathological manifestations and/or collapse of the structure. Therefore, it is intended to conduct a comparison between the methods of conventional analysis, axial stiffness increaser, called the approximate method, and incremental analysis, seeking to understand the main differences in terms of internal forces and the design of buildings. For this purpose, softwares for modeling, analysis, and structural design that allow the simulation of these strategies will be used.
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