Relation between pore structure uniformity and compressive strength of iron tailings mortar

Abstract

Pore structure uniformity is one of the key factors affecting the compressive strength of mortar. This study proposed two new methods to characterize the uniformity of pore distribution and established their relationship with compressive strength. Compressive and pore structure tests were carried out on ordinary mortar, iron tailings mortar, and iron tailings mortar containing basalt fibers and polyacrylate emulsion. The first method uses the quadrat-based method calculated based on pore area and regional distribution, while the second method utilizes the average nearest neighbor index determined based on the distance between pore boundaries. Correlation analysis was used to model the relation between pore distribution uniformity and compressive strength. The results showed that iron tailings, basalt fibers and polyacrylate emulsion all reduced the compressive strength and pore distribution uniformity of mortar. The standard deviation of porosity and the average nearest neighbor index can accurately characterize the uniformity of pore distribution of mortar. Both methods show strong linear correlations with the compressive strength, in particular with the average nearest neighbor index. By introducing new methods to accurately characterize the uniformity of the pore distribution of mortar, this study provides the theoretical basis for in-depth understanding of the influence of pores on the macroscopic properties of materials.