Delihowski Jurij, Izak Piotr, Wojcik Łukasz, Stempkowska Agata, Jarosz Marcin
Faculty of Materials Science and Ceramics, AGH University of Kraków, Krakow, Poland.
Faculty of Civil Engineering and Resources Management, AGH University of Kraków, Krakow, Poland.
Sci Rep. 2024 Sep 14;14(1):21485. doi: 10.1038/s41598-024-72315-0.
This study examines the influence of different grain size fractions of coal fly ash on the properties of clay-cement mortars used in flood levee construction. Dry aerodynamic separation and mesh sieving were used to obtain ultrafine, fine, and medium fractions of high-calcium and silica fly ash. The experimental results reveal that the rheological properties of fresh mortars are significantly influenced by these fractions. High-calcium fly ash mortars exhibit high reactivity and rapid increase in viscosity, with finer fractions showing the highest reactivity. Silica ashes show increased reactivity in the later stages of suspension hardening. Their spherical shape contributes to reducing internal friction during flow in initial technological operations. Furthermore, the compressive strength of hardened mortars improves as the particle size decreases for both ashes, resulting in a dense and uniform microstructure. The separation and fractionation of fly ashes contribute to the obtaining of fractions that influence the parameters of clay-cement suspension application on different scales. The results show the potential benefits of ash separation, which can bring advantages in terms of economic viability, engineering performance, and ecological sustainability.
本研究考察了不同粒度级分的粉煤灰对防洪堤建设中使用的黏土水泥砂浆性能的影响。采用干式空气动力分选和筛网筛分法，获得了高钙粉煤灰和硅灰的超细、细和中等粒度级分。实验结果表明，这些级分对新拌砂浆的流变性能有显著影响。高钙粉煤灰砂浆表现出高反应活性和粘度快速增加的特性，粒度越细反应活性越高。硅灰在悬浮硬化后期反应活性增加。其球形形状有助于在初始工艺操作的流动过程中降低内摩擦力。此外，两种粉煤灰硬化砂浆的抗压强度均随粒径减小而提高，从而形成致密均匀的微观结构。粉煤灰的分离和分级有助于获得能在不同尺度上影响黏土水泥悬浮液应用参数的级分。结果显示了灰分分离的潜在益处，这在经济可行性、工程性能和生态可持续性方面都能带来优势。
