Optimización del diseño de conexiones para arriostramientos verticales en estructuras mixtas de hormigón-acero
2021
Tesis
es
Autores
Profesor/a Guía
Notas
Memoria (Ingeniero Civil)
Resumen
El documento se centra en evaluar las conexiones en arriostramientos verticales en estructuras
mixtas, debido al diseño por capacidad que se exige en el acápite 8.5.2 de la NCh2369.Of2003.
Considerando que chile es un país sísmico, en donde, más de un 80% de las riostras son utilizadas para
limitar la deformación de la estructura y su perfil no está definido por el esfuerzo que recibe, se presentan
conexiones sobredimensionadas bajo el diseño que propone la normativa. Para abordar esta problemática,
basado en información recopilada de papers, normas y verificaciones descritas en los códigos ANSI/AISC,
se diseñaron conexiones para el esfuerzo que recibe el perfil y por capacidad, para una estructura en
particular diseñada bajo un sistema sismorresistente mixto, en donde, se realizó una comparación de área,
peso y gasto económico en las conexiones entre ambos diseños, para finalmente realizar una verificación a
través de elementos finitos a cada conexión y ver cómo responden. Basado en los resultados se observó una
disminución de área y peso en el diseño de las conexiones mayor al 60%, lo que representa en la estructura
una diferencia de 10.817 kgf entre ambos diseños, reduciendo así el gasto económico en $6.598.514.
Teniendo en consideración lo mencionado y que todas las conexiones pasaron las verificaciones por
elementos finitos, se puede concluir que el diseño más conveniente es considerando el esfuerzo último,
debido a las ventajas de poder reducir el acero que se utilizará en un proyecto y el gasto económico que esto
significa, evidenciando un sobredimensionamiento por parte del diseño por capacidad, al tener un perfil
definido por el drift en estructuras mixtas.
The document focuses on evaluating the connections in vertical bracing in mixed structures, due to the capacity design required in section 8.5.2 of NCh2369.Of2003. Considering that Chile is a seismic country, where more than 80% of the bracing are used to limit the deformation of the structure and its profile is not defined by the stress it receives, consequently occur oversized connections under the design proposed by the normative. To address this problem, based on information collected from papers, normative and verifications described in the ANSI / AISC codes, connections were designed for the effort received by the profile and by capacity, for a particular structure designed under a mixed seismic-resistant system, where, a comparison of area, weight and economic expense was made in the connections between both designs, to finally carry out a verification through finite elements to each connection and see how they respond. Based on the results, a decrease in area and weight was observed in the design of the connections greater than 60%, which in the structure represents a difference of 10,817 kgf between both designs, thus reducing the economic expense by $ 6,598,514. Taking into consideration the aforementioned and that all the connections passed the finite element verifications, it can be concluded that the most convenient design is considering the last effort, due to the advantages of being able to reduce the steel used in a project and the economic expense, evidencing an oversizing by capacity design, having a profile defined by the drift in mixed structures.
The document focuses on evaluating the connections in vertical bracing in mixed structures, due to the capacity design required in section 8.5.2 of NCh2369.Of2003. Considering that Chile is a seismic country, where more than 80% of the bracing are used to limit the deformation of the structure and its profile is not defined by the stress it receives, consequently occur oversized connections under the design proposed by the normative. To address this problem, based on information collected from papers, normative and verifications described in the ANSI / AISC codes, connections were designed for the effort received by the profile and by capacity, for a particular structure designed under a mixed seismic-resistant system, where, a comparison of area, weight and economic expense was made in the connections between both designs, to finally carry out a verification through finite elements to each connection and see how they respond. Based on the results, a decrease in area and weight was observed in the design of the connections greater than 60%, which in the structure represents a difference of 10,817 kgf between both designs, thus reducing the economic expense by $ 6,598,514. Taking into consideration the aforementioned and that all the connections passed the finite element verifications, it can be concluded that the most convenient design is considering the last effort, due to the advantages of being able to reduce the steel used in a project and the economic expense, evidencing an oversizing by capacity design, having a profile defined by the drift in mixed structures.
Editor
Universidad Andrés Bello