Crawford, Robert H
CATEGORIES2022 Conference Papers Conference Papers
In mitigating the effects of climate change, life cycle assessment (LCA) has been proposed as a design tool to facilitate the choice of structural typologies, materials and floor plan layouts for tall buildings. Existing studies that use LCA to compare alternative structural systems for tall buildings adopt regular floor plans, whereby their centres of mass, stiffness and strength coincide throughout the building height. Thus, existing comparative LCA studies of structural systems exclude torsionally unbalanced tall buildings. The aim of this paper is to demonstrate the detrimental influence of plan irregularity on the embodied greenhouse gas emissions (EGHGE) of structural systems for tall buildings. This influence is evaluated using three finite element models of structural systems with varying degrees of plan irregularity for a 15-storey building scenario. The eccentric placement of shear walls is amplified across the alternative structural designs for each scenario, yet the materials and typology are kept constant to isolate the influence of plan irregularity on the EGHGE of the structural systems. All three structural systems comprise reinforced concrete shear walls and a moment-resisting frame that consists of band beams, columns and one-way slabs. A hybrid life cycle inventory analysis method is used to quantify the EGHGE of the structural systems. The findings of this study provide an initial estimation of the EGHGE premium for plan irregularity and confirm the need to reduce and eliminate these irregularities in the aim of minimising the EGHGE of structural systems for tall buildings.
Keywords: embodied environmental flows; high-rise; premium for height; structural systems.