Optimización de mallas estructurales de acero envolventes de edificios en altura. Análisis de las direcciones principales identificadas por sus líneas isostáticas

Resumen

The Dissertation's main aim is to establish a procedure for the optimization of space grid as a framed tube (spatial mesh) structural typology envelope for tall buildings given the increasing interest in this recent constructive and architectural trend. As to accomplish this aim, a comparative structural study is driven, rooted in the analysis of the principal stresses, to determine whether spatial mesh envelopes for tall buildings are more optimal and efficient if their design is adapted to the principal stress directions. Thus, meaning when the design of this structural typology is based on the isostatic lines of their equivalent continuous structural elements according to their solicitations. This approach requires to establish, previously, the fundamental relationship formed by the basic concepts of geometry, shape and structural function. The first chapter, therefore, is a deep overview oft hese concepts. The chapter outlines the historical knowledge to determine the state-of-the-art according to their use in the design and analysis of architectural projects, based on a documentary compilation in which the baseline is to seek of understanding structural. Hence, allowing to establish a basic historical conceptual thread that in the course of its evolution shells the various formal aspects of the function-form relationship. In chapter 2, a basic comparative study is performed, in two dimensions, around different triangulations of lattice girder to determine the relationship between structural efficiency and the arrangement of the bars that make up the trusses, as adapted to the isostatic lines trajectory of their equivalent continuous structural elements, previously mentioned. The basic study, around efficiency and structural behavior, is implemented later in the analysis of more complex spatial structures, which are the main object of this research. Matter of factly, this concept of structural optimization, used according to the form, allows this research to address the study of skyscrapers based on spatial mesh as a framed tube resistant system in the field of architecture. As justified in the third chapter and more thoroughly discussed in chapter 4 this current trend is frequently used. lts use is due to the high architectural and structural features offered by this structural type, which is characterized by the close relationship of the binomial that conform the architectural design and structural concept. In chapter 5, a proposal is outlined according to the final structural comparative studies. by presenting an architectural proposal that includes the so-called concept "structural aesthetics" that emerges from the binary concept previously mentioned, which is widely used in the design and analysis of architectural structures. Chapter 6 is devoted to the analysis of the data, the findings of the comparative studies conducted, in accordance with the structural efficiency, are presented. These results will determine if the mesh or framed tube structures are more efficient if they adopt the isostatic lines trajectory generated by the main and dominant lateral load, in the high-rise buildings case, the wind. Conjointly, in this chapter the possible future research lines derived from the above conclusions are outlined .