Analysis of Reinforced Concrete Spatial Structures with Different Structural Openings and Forms

Abstract

The first reinforced concrete spatial structures date from 1920. Since then, their popularity has increased as a new structural system with widely used materials like reinforced concrete. The building trend of these structures faded near 1970s, because of the high costs in formwork and labor work compared to other structural systems, but also the high calculations difficulty and the lack of knowledge for their structural behavior strongly connected with their form. The technological evolution of formworks, like air inflated forms or polymer modular formwork, as well as the technological advance of computer and software industry for civil engineering through automation of numerical methods and creation of new algorithms, have helped to reach new levels of expertise during the conceptual and structural design process. The scope of this analytical study is the use of structural openings to create new lighter, sustainable and architectural forms of structures, using a new approach to the form finding process. The paper includes structure cyclic analysis due to finding the appropriate position and geometrical form of the openings considering stresses, deformations and boundary conditions of specific cases. Optimizations and analysis are made using advanced optimization algorithms of form finding and topological optimization (ATOM – Abaqus Topology Optimization Module ®) and FEM based software for static and seismic analysis. Based on the analysis data of the case examples for the new designing approach to structural openings and forms, presented on this paper with the use of advanced software technology, we conclude that spatial structural system in 21st century should be considered as the next engineering challenge in conjunction to architectural trends for free, irregular and diverse forms.