Evaluación de edificios de mediana altura en estructura de acero con diagonales excéntricas, concéntricas

Abstract

The purpose of this research project is to use stiffening systems that allow for better structural performance in the presence of seismic events by comparing structural energy dissipation systems such as: buildings with concentric diagonals in the form of x and buildings with eccentric diagonals with a link length of 1 meter in medium-rise steel buildings considering the mechanical and physical properties of these elements as well as the implementation and construction advantages. In this project, two 20-story steel buildings were compared, which have seismic stiffening systems that were located symmetrically in the structure, for modeling the ETABS 2016 software was used, applying the Ecuadorian Construction Standard (NEC-15). ), as well as the verification of compliance with the AISC 341-16 standard, from which an optimal seismic-resistant structural design was obtained that is within the permitted parameters. The use of concentric and eccentric diagonals allows to guarantee the stability in the structure, to obtain an appropriate structural behavior that allows to be able to minimize the horizontal movements caused by the earthquakes and the wind, it requires a greater rigidity and stability to the structure. The result was obtained by using concentric diagonals a vibration period of 2.037 seconds, the inelastic floor drift was 0.0129 mm, likewise the value of static and dynamic shear were 580.78 and 464.62 respectively, while when using eccentric diagonals the period of vibration was 1.921 seconds, with inelastic floor deviations of 0.0118 mm, complying with the requirements established by the NEC-15 norm, in the same way a static shear of 615.868 and a dynamic shear of 492.695. Additionally, a non-linear static analysis (Pushover) was carried out, where a load pattern was applied to all the nodes that join the main beams and columns, which is related to the modal shapes of the first two vibration modes of the steel structure. of medium height, where from the static capacity curve it was possible to observe that in the two models used concentric diagonals as well as eccentric diagonals the result is similar in terms of resistance drops, however compared to the concentric system, the system of Eccentric diagonals have higher ductility.