Correlation of petrographic and chemical characteristics with strength and durability of basalts as railway aggregates determined by ballast fouling

The most important methods that are used to estimate ballast fouling are the Los Angeles abrasion and MgSO₄ tests. The effects of chemical and mineralogical properties of basalts on ballast fouling have not been investigated sufficiently. The aim of this study was to investigate the chemical, mineralogical, and aggregate properties of different basaltic rocks and to evaluate them for ballast fouling. Aggregate samples were collected from different locations in Turkey. Their mineralogical, petrographic, chemical, and physicomechanical properties were determined. Aggregate tests were conducted on these samples. Los Angeles abrasion and MgSO₄ test results were compared with other test results, and their effect on ballast fouling was investigated. The test results were analysed using simple linear regression. The Los Angeles abrasion value increased with an increase in SiO₂ and Al₂O₃ content but decreased with the amount of Fe₂O₃, CaO, and MgO. The MgSO₄ value decreased with the amount of SiO₂ and plagioclase content. The content of plagioclase and opaque minerals affected ballast fouling more than other minerals in basalt aggregates.