Study on Enhancing the Mechanical Properties of Solid Waste Based Solidification Materials Using Response Surface Methodology

To enhance the efficient utilization of solid waste, such as tailings and steel slag, in solidification materials for green mining, achieving high material performance through precise compatibility is essential. This study employed the response surface methodology to optimize solidification materials primarily composed of iron tailings, steel slag, and blast furnace slag. During the optimization process, the contents of basalt fiber (BF), polypropylene fiber (PPF), and desulfurized gypsum (DG) were selected as variable factors, while the 28-day flexural and compressive strengths of the mortar served as evaluation indices. A mathematical prediction model was established to provide parameters for optimizing these variables. Experimental results indicated that the optimal mechanical properties were achieved when the mass contents of BF, PPF, and DG were 0.1%, 0.05%, and 8%, respectively. The primary phases of the samples included ettringite, calcite, clinoferrosilite, and anorthite. The experimental and predicted values for 28-day flexural and compressive strengths were 5.5/5.7 MPa and 26.3/26.9 MPa, respectively, with relative errors of only 3.64% and 2.28%. The response surface methodology exhibited high prediction accuracy and scientific validity, offering a novel approach and a solid basis for the multi-objective optimization of solidification materials in green mining.