Performance study and engineering application of grouting materials with a large content of solid waste

With the proposal of "2030 carbon peak, 2060 carbon neutralization" of China, cement was one of the high emission industries, which urgently needs to reduce the content of cement in cement products as much as possible. In this work, the pre-stressed grouting materials with a large content of fly ash (FA) or steel slag powder (SS) was prepared. The effect of FA and SS on the fluidity, mechanical properties and pressure bleeding rate of grouting materials was comparatively studied, and the maximum content was thus determined. The effect of FA and SS on the microscopic properties of grouting materials was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and Thermogravimetric analysis (TG) tests. Economic and environmental benefits also were analyzed. Box girder scale model experiment was performed to study the process adaptability and grouting ability of the grouting material with 40% FA (FA40). Finally, FA40 was successfully applied to a box girder with the length of 30 m, and nondestructive determination was conducted to analyze the grouting ability. The results showed that the optimum content of FA and SS was determined as 40% and 20% respectively. FA40 and the grouting materials with 20% SS (SS20) both showed good fluidity, bleeding performance and mechanical properties, as well as good economic and environmental benefits. FA40 showed excellent filling property and process adaptability in box girder scale model and box girder with the length of 30 m. The bellow was densely filled and the steel strand was tightly wrapped by FA40, and no defects had been detected.