Understanding and Reducing Overdesign in Structural Engineering

2019年，英国议会宣布气候变化为气候紧急状态。结构工程师协会（IStructE）遵循这一宣言，成立了气候紧急情况工作组（CETG），并从那时起通过出版物，杂志文章和研讨会强调了结构工程师在应对气候紧急情况方面的责任。例如，最近IStructE出版物《零设计》指出，结构工程师需要“在计算中将碳与安全同等重要”。研究表明，过度设计在结构工程中很常见，从使用高于欧洲规范推荐的外加荷载，到典型的利用系数0.8。研究表明，这种过度设计部分来自设计的不确定性，对现场质量保证的担忧，以及对结构行为的潜在缺乏了解。一些超设计是不可避免的，利用系数很难达到1-例如，钢筋梁中所需的钢筋面积可能必须根据可用的钢筋尺寸进行四舍五入。然而，结构工程师需要意识到设计决策的碳影响，并避免不必要的过度设计。本研究旨在了解过度设计的原因，并考虑如何降低过度设计的水平。为了实现这一目标，将采访影响结构工程设计和施工决策的个人，以确定他们认为过度设计是什么，为什么他们认为过度设计会发生，以及气候紧急状态的宣布是否改变了他们的设计决策方法。将进行这种定性分析，为更大规模的定量研究提供问题信息。通过对调查结果的分析，将调查一些已确定原因的潜在解决方案。

Climate change was declared a climate emergency by the UK Parliament in 2019. The Institute of Structural Engineers (IStructE) followed this declaration with the creation of the Climate Emergency Task Group (CETG) and since then have highlighted the responsibility of the structural engineer in tackling this climate emergency through publications, magazine articles and seminars. For example, a recent IStructE publication, Design for zero, stated that structural engineers need to "make carbon as important as safety in our calculations".Research shows that overdesign is common in structural engineering, from the use of imposed loads that are higher than recommended by the Eurocode, to a utilisation factor of 0.8 being typical. Research suggests that some of this overdesign comes from design uncertainty, concerns about quality assurance onsite, and a potential lack of understanding of structural behaviour. Some overdesign is unavoidable, a utilisation factor of exactly 1 is difficult to achieve - for example, the required area of steel in a reinforced beam will likely have to be rounded up based on available bar dimensions. However, structural engineers need to be aware of the carbon impact of design decisions and avoid unnecessary overdesign. This research aims to understand the causes of overdesign and consider ways to reduce the level of overdesign that takes place. To achieve this aim, individuals who influence structural engineering design and construction decisions will be interviewed to determine what they consider overdesign, why they think overdesign occurs and if the declaration of the climate emergency has changed their approach to design decisions. This qualitative analysis will be carried out to inform the questions for a larger quantitative study.From the analysis of the findings, potential solutions to some of the identified causes will be investigated.