Testing concrete-encased steel from the 1950s for direct reuse

钢是最有用的建筑材料之一。它坚固、耐用、高效，自19世纪中期以来一直在我们的建筑环境中发挥作用。它也很容易回收--事实上，废物流中的大部分废钢已经被捕获并适当地回收成新的钢铁。但这只是故事的一半。制造新的钢铁需要包括煤在内的有限的材料。制造新的和回收的钢铁需要1500摄氏度以上的炉温，这意味着大量的能源使用。即使能源可以来自可再生能源，化学过程本身也会释放二氧化碳，一种温室气体。目前的钢铁制造方法不可能脱碳。这意味着我们将无法在净零经济中使用现有方法制造钢铁。钢铁通常存在于现有建筑物中。当这些建筑物被拆除时，钢铁被废弃，熔化并回收到新的钢铁制品中。虽然这听起来很积极，但这是一个非常耗能的过程。一些制造方法不能容纳大量的废钢。在英国，我们产生的废料超过了我们的处理能力，其中75%最终被出口。我们需要关闭材料循环，避免再制造，因为现有钢材可以完美地重复使用。再利用钢材的碳足迹比传统钢材小八倍。1970年以后生产的钢材遵循标准制造工艺和尺寸，因此很容易验证其可再利用性。钢结构研究所有一个标准的方法来遵循这些部分进行检查，以重复使用。但现代炼钢始于1855年，因此这遗漏了很大一部分现有钢材。该项目旨在通过进行严格的材料测试和质量分析，验证伦敦四座被拆除的建筑中的大量20世纪50年代钢材库存，并提出了一个再利用的潜力，以保持钢铁在其最高价值。该项目是创新的，因为它扩展了知识和理解的范围目前的协议没有涵盖的材料库存，可能有助于更大比例的现有钢铁制品的再利用，有助于进一步关闭材料循环。

Steel is one of the most useful construction materials. It is strong, durable and efficient, it has been instrumental in our built environment since the mid-1800s. It is also easy to recycle -- in fact, most of the scrap steel in waste streams is already captured and properly recycled into new steel.But this is only one half of the story. Making new steel requires finite materials including coal. Making new and recycled steel requires furnace temperatures above 1500 degrees C, which means intense energy use. Even if the energy could be sourced from renewables, the chemical process itself releases carbon dioxide, a greenhouse gas. Current methods of steel manufacture are impossible to decarbonise.This means we will not be able to manufacture steel using current methods in a net zero economy.Steel is commonly found in existing buildings. When those buildings are demolished, the steel scrapped, melted and recycled into new steelwork. While it sounds positive, it is very energy-intensive process. Some manufacturing methods cannot accommodate high volumes of scrap steel. In the UK, we generate more scrap than we can deal with, and 75% of it ends up being exported.We need to close the materials loop and avoid remanufacturing when existing steel can be in perfect shape to be simply reused. Reused steel has a carbon footprint eight times smaller than traditional steel.Steel made after 1970 was subject to standard manufacturing processes and sizes, so it is easy to validate for reuse. The Steel Construction Institute has a standard method to follow for those sections to be checked for reuse. But modern steelmaking started in 1855, so this leaves out a significant proportion of existing steel.This project aims to validate a large stock of 1950s steel from four deconstructed buildings in London, by undertaking rigorous materials testing and quality analysis, and coming up with a reuse potential to keep the steel at its highest value.The project is innovative because it extends the scope of knowledge and understanding to a stock of materials that is not covered by current protocols and might facilitate the road to reuse for a larger proportion of existing steelwork, helping to further close the materials loop.