Improving Railway Track Durability: Evaluating Sand and Emulsion Effects on Cement Asphalt Mortar

The degradation of railway substructures due to fouled ballast is a critical concern in railway infrastructure management. This study explores the use of Cement Asphalt Mortar (CAM) as a novel stabilizing agent to address fouled ballast issues. The research systematically examines the influence of sand content and various emulsifiers on CAM’s engineering properties through comprehensive testing. Notably, anionic and nonionic emulsifier mixtures exhibited exceptional stability, with residue content ranging from 0.5% to 4%, while cationic emulsifier mixtures showed higher residue content (9% to 14%). Moreover, the inclusion of sand significantly enhanced CAM mixture strength, with a Sand/Cement (S/C) ratio of 50% demonstrating the highest strength, reaching 0.35 MPa after 2 hours and substantial strength gains over 28 days of curing. Dynamic modulus testing underscored the favorable impact of sand content, particularly at lower temperatures, emphasizing the importance of sand and emulsifier types in improving CAM’s engineering properties.