Linz-Donawitz (LD) slag, solid waste produced during steel manufacture in basic oxygen furnace, is difficult when it comes to handling and disposal and has very limited utilization. To increase its reusability, the suitability of supplanting cement with LD slag in concrete was examined. To study the impact of partially replacing cement with LD slag on strength, microstructure, and durability of concrete, more than 150 samples were cast. The test results reveal that the highest compressive and flexural strengths were attained at 20% LD slag replacement and, beyond that, the strength decreased. The hydration products detected by X-ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) were calcium silicate hydrate (C-S-H), ettringite, and calcium aluminosilicate hydrate (C-A-S-H). The scanning electron microscope (SEM) images of binary cement concrete showed denser microstructure and lesser voids. The sulphuric acid resistance, electrical resistivity, and carbonation resistance tests done reveal that acceptable durability could be achieved when cement is replaced by LD slag. It is deduced that LD slag can be utilized in partially replacing cement to achieve the desired strength. This research gives another comprehension of simultaneously managing steel industry waste for sustainable development and contributing added advantages to the economy.

中文翻译：

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Linz-Donawitz炉渣废料替代水泥中水泥的可持续方法：机械，微观结构和耐久性能

Linz-Donawitz（LD）炉渣是碱性氧气炉在炼钢过程中产生的固体废物，在处理和处置方面非常困难，并且利用率非常有限。为了提高其可重复使用性，研究了用LD矿渣替代水泥在混凝土中的适用性。为了研究用LD炉渣部分替代水泥对混凝土强度，微观结构和耐久性的影响，共铸造了150多个样品。测试结果表明，在20％LD炉渣置换量下，可获得最高的抗压强度和抗弯强度，除此之外，强度降低。通过X射线衍射（XRD）和傅立叶变换红外光谱（FTIR）检测到的水合产物为硅酸钙水合物（CSH），钙矾石和硅铝酸钙水合物（CASH）。二元水泥混凝土的扫描电子显微镜（SEM）图像显示出更致密的微观结构和更少的空隙。进行的耐硫酸，电阻率和抗碳化性能测试表明，用LD炉渣代替水泥可以达到可接受的耐久性。可以推断出LD渣可用于部分替代水泥以获得所需强度。这项研究为同时管理钢铁工业废物以促进可持续发展和为经济带来更多优势提供了另一种理解。可以推断出LD渣可用于部分替代水泥以获得所需强度。这项研究为同时管理钢铁工业废物以促进可持续发展和为经济带来更多优势提供了另一种理解。可以推断出LD渣可用于部分替代水泥以获得所需强度。这项研究为同时管理钢铁工业废物以促进可持续发展和为经济带来更多优势提供了另一种理解。