This paper presents an objective methodology to assess material overuse through the determination of a Structural Efficiency parameter for building structures, and to demonstrate the feasibility of such measurement while providing preliminary results to support its importance.

Despite the current scenario of climate emergency, building structures are evolving towards more material-demanding systems while designers, industry and the general public remain unaware of the related resource and energy waste. This may be, in part, because of the lack of an absolute, unified, consistent and objective way to assess material usage in building structures.

The proposed methodology can be consistently applied across all materials, layouts and building uses, providing absolute measurements while considering the project-specific features. The initial results obtained show how floor typologies have evolved towards less efficient solutions driven by labour costs and the quest for thinner floors and longer spans. They also indicate that current buildings are consuming at least 16 to 80 times more structural material (equivalent to efficiencies between 6.25% and 1.25%) than the minimum theoretically required. Theoretical models do not follow the same parameters as the real designs, thus 100% efficiency is not necessarily the final goal; realistic targets could be those obtained from the energy sector and, once the efficiency measurement becomes mainstream, improvements from current average 4% efficiency to around 25% should be achievable within 20 years.

In near-optimal solutions, structural requirements are sensitive to the building layout but less sensitive to site conditions (wind, snow, ground conditions, etc.). Self-weight is small compared to typical existing systems hence it becomes secondary. Selecting materials with a low working strain is key in highly efficient floor systems, to avoid over-sizing for serviceability.

Considering the global importance of building structures’ material consumption and embodied carbon, the construction industry must start measuring Structural Efficiency to systematically appraise the current material overspend and the potential savings, while investing in R&D of new structural systems driven by material efficiency, incorporating the latest technologies in automation and digital manufacturing.

Material research should shift towards lower working strains instead of focusing on material strength.

本文提出了一种客观的方法，可以通过确定 建筑结构的结构效率参数来评估材料的过度使用 ，并说明这种测量的可行性，同时提供初步结果以支持其重要性。

尽管当前存在气候紧急情况，但是建筑结构正在朝着对材料更加苛刻的方向发展，而设计师，工业界和公众仍然不了解相关的资源和能源浪费。这可能部分是由于缺乏一种绝对，统一，一致和客观的方法来评估建筑结构中的材料使用情况。

所提出的方法可以始终适用于所有材料，布局和建筑用途，在考虑项目特定功能的同时提供绝对测量。获得的初步结果表明，地板类型是如何朝着由人工成本以及对更薄地板和更长跨度的追求驱动的效率较低的解决方案发展的。他们还指出，目前的建筑物消耗的结构材料比理论上的最低要求至少高16到80倍（相当于6.25％至1.25％之间的效率）。理论模型没有遵循与实际设计相同的参数，因此100％的效率不一定是最终目标。现实的目标可以是从能源部门获得的目标，一旦效率衡量成为主流，

在接近最佳的解决方案中，结构要求对建筑物布局敏感，但对工地条件（风，雪，地面条件等）较不敏感。与典型的现有系统相比，自重很小，因此它成为次要的。选择具有低工作应变的材料是高效地板系统的关键，以避免尺寸过大的可维修性。

考虑到建筑结构材料消耗和内含碳的全球重要性，建筑行业必须开始测量结构效率，以系统地评估当前的材料超支和潜在节省，同时投资于由材料效率驱动的新结构系统的研发，并结合最新自动化和数字制造技术。

材料研究应该转向较低的工作应力，而不是专注于材料强度。