Optimal analysis of tall building form to improve urban livability and energy efficiency using the Caramba plugin

Abstract

In recent decades, the increasing development of tall buildings in metropolitan areas has become one of the main indicators of the vertical expansion of cities. These structures are of particular importance not only due to their specific requirements in design and implementation, but also as prominent elements in the urban landscape, they play a key role in spatial identity. One of the most important challenges in designing tall buildings is choosing architectural forms that can simultaneously meet the requirements of aesthetics, structural efficiency, and stability against lateral loads such as earthquakes.

The present study aims to investigate the effect of floor plan geometry and their height scale on the structural performance of tall buildings, using the genetic algorithm optimization method in the Grasshopper environment and the Caramba plugin. In this regard, lateral displacement as an indicator of seismic vulnerability and unit weight of the structure surface as an indicator of structural efficiency have been analyzed as objective functions. By performing multi-objective analysis and defining geometric variables in the form of a parametric model, a set of optimal forms was produced that can be used as the basis for the designer's decision-making, depending on the design priorities. The research findings indicate that forms with a simple (triangular) roof plan and a compact scale in height have better performance from a seismic and weight perspective. On the other hand, the results show that the final design response does not simply have a definitive answer, but rather in the form of a "Pareto set of answers" the designer can select the final form based on criteria such as visual beauty, harmony with the climate and the project context. The final analysis of the models was performed in the Grasshopper parametric environment and its results can be used in a generalizable format for similar projects with diverse climatic and structural conditions