Sanjuán Miguel Ángel, Menéndez Esperanza, Recino Hairon
Spanish Institute of Cement and its Applications (IECA), C/José Abascal, 53, 28003 Madrid, Spain.
The Eduardo Torroja Institute for Construction Science (Spanish National Research Council, CSIC), C/Serrano Galvache, 4, 28033 Madrid, Spain.
Materials (Basel). 2022 Apr 18;15(8):2933. doi: 10.3390/ma15082933.
Ternary Portland cements composed of coarse silica fume (SF), limestone (LS), and Portland cement (PC) can afford some environmental advantages by reducing the clinker content in Portland cements. These cements will help to reduce the clinker factor target from 0.78 to 0.60 by 2050 with the aim to be climate neutral. Silica fume (SF) possesses pozzolanic properties that enhance mechanical strength and durability. By contrast, limestone powder has three main outcomes, i.e., filler, dilution, and chemical effects. The first reduces porosity and refines the microstructure of mortars and concretes. The second decreases the amount of hydration products and increases the porosity; the third one promotes the appearance of carboaluminates and reduces porosity. This paper covers the mechanical properties of Portland cement-limestone-coarse silica fume ternary cements, and its synergetic mechanism. Compressive and flexural strength of mortar at 2, 7, 14 and 28 days was performed. Coarse silica fume has a minor contribution on the nucleation effect compared to ground limestone at early ages. The nucleation and filler effects, at early ages, are less pronounced in coarse and very fine limestone powder. The highest compressive strength at 28 days is reached with the lowest content of coarse silica fume (3%). Mortar mixes made with a high level of limestone presented a delay in the compressive strength development.
由粗硅灰（SF）、石灰石（LS）和波特兰水泥（PC）组成的三元波特兰水泥，通过降低波特兰水泥中的熟料含量，可带来一些环境效益。这些水泥将有助于到2050年将熟料系数目标从0.78降至0.60，目标是实现气候中和。硅灰（SF）具有火山灰特性，可提高机械强度和耐久性。相比之下，石灰石粉有三个主要作用，即填充、稀释和化学作用。第一个作用是降低孔隙率并细化砂浆和混凝土的微观结构。第二个作用是减少水化产物的数量并增加孔隙率；第三个作用是促进碳铝酸盐的出现并降低孔隙率。本文涵盖了波特兰水泥 - 石灰石 - 粗硅灰三元水泥的力学性能及其协同机理。对2、7、14和28天龄期的砂浆抗压强度和抗折强度进行了测试。与磨细石灰石相比，早期粗硅灰对成核效应的贡献较小。在早期，粗石灰石粉和极细石灰石粉中的成核和填充效应不太明显。粗硅灰含量最低（3%）时，28天抗压强度最高。高石灰石含量的砂浆混合物抗压强度发展出现延迟。
