The transition towards a more sustainable construction sector is increasingly acknowledged as essential for mitigating environmental impacts and improving the resilience of the built environment. By integrating Life Cycle Thinking (LCT) principles from the early stages of design, structural engineers can significantly influence the sustainability of a structure throughout its entire life cycle. Life Cycle Structural Engineering (LCSE) can indeed foster the design and construction of buildings that are not only efficient and resilient but also minimize environmental impacts over their entire life cycle. This approach ensures that sustainability is embedded into the construction process, contributing significantly to achieve broader environmental and societal goals.
In this paper, the concept of LCSE is further investigated. First, the macro-objectives to be pursuit for a more sustainable and resilient construction sector are described, also analyzing the compliance with the global and European goals for sustainability. Then, LCT-based design criteria to be introduced since the early stages of the design are discussed, e.g., design for disassembly, for adaptability, for durability, etc. Technical choices, design targets and structural models/schemes aimed at translating the sustainable objectives into current practice are introduced. For instance, incorporating time-dependent structural models that represent the potential progression of material decay can enhance the understanding of how structural performance evolves over time, leading to more precise maintenance of buildings and infrastructures; adopting novel design targets, such as full operability at LSLS with damage control, can remarkably reduce indirect losses and impacts associated to recovery; conceiving novel structural schemes, such as shell structural systems, can reduce overstresses of the foundation, thus avoiding the construction of relevant foundation works; or adopting LCT-based structural details, such as standardized, demountable, plug-and-play connections, may reduce impacts during the construction, maintenance and deconstruction phases and increase the reuse rate. Some best practice examples, both in terms of innovative techniques and real applications, are thus presented. Finally, LC metrics/KPI able to verify the sustainability of the technical choices are reviewed.