Life Cycle Analyses Integration in Structural and Environmental optimizations of Steel-Framed Structures

Lowering environmental effects has lately been a key objective of structural optimization due to the significant amount of CO2 emissions in the civil engineering sector and the increased attention on environmental concerns and sustainable development. This thesis introduces an approach for the simultaneous optimization of steel space frame structures’ size, shape, and topology. The study’s originality stems from the specification of the objective function, which takes into consideration environmental issues by integrating the Life Cycle Assessment method in addition to conventional mass minimization. More specifically, the ideal number of elements, in terms of beams and nodes, has been investigated based on manufacturing and practical considerations. Additionally, structural buckling verification, which is the most problematic type of instability for steel structures to control, has been incorporated into the OF. The introduction of structural optimization techniques’ fundamental concepts, their application in civil engineering, and the terminology needed to comprehend how the LCA methodology works served as the foundation for the dissertation. In Chapter 2, an in-depth review of the recent literature on environmental structural optimization is presented. To appropriately examine the structural typology in a subsequent phase, the major theoretical case study has been studied and depicted in Chapter 3. First, a brief description of space frame structures has been provided, highlighting the key characteristics, issues, and civil engineering applications. After then, the effectiveness of the software and the parametric design method were covered. In an attempt to go closer to the case study’s primary highlights, a summary of the design variables taken into consideration has been presented and detailed in depth, along with the model’s description and any pertinent analysis choices. The purpose of this initial phase, which focuses on fully understanding the behavior of such internally hyperstatic structures, is to optimize the structure only by minimizing mass. The efficiency of the developed structure and the suggested objective function were analyzed. Once the method had been tested on a theoretical level, it was possible to advance to a greater scale by considering the real-world case of an industrial structure with a single story in Chapter 4. Both gravitational and lateral loadings have been taken into consideration to create a more realistic portrayal. The environmental formulation of the OF is now covered and discussed in terms of both internal tool development and data collecting. The numerical outcomes for the industrial building’s size, shape, and topology optimization have been provided in Chapter 5. To demonstrate how the findings of this study might inspire other innovations, and more especially to build a more sophisticated tool in the future to integrate environmental considerations in the early design phases, potential future advances for such analysis have been outlined in Chapter 6.