Abstract:
This research investigates conditions of railway substructures at Mae Tarn Noi Station, Hangchat District, Lampang Province. The specimens are collected from railway substructure at several points in a cross-section. The specimens are subjected to laboratory tests as follows: sieve analysis, hydrometer, specific gravity, water absorption, Los Angeles abrasion, aggregate
compression value, aggregate impact value, flat and elongation, sulfate soundness, Atterberg limit, and scanning electron microscopy. In-situ tests, i.e. unit weight and water content, are also performed at these locations in a cross-section. Test results indicate substructure conditions of Northern line railway and they are compared with AREMA standard. The results
are employed to analyze ballast fouling characteristics by various theories to obtain quantitative indexes of the quality of ballast. Moreover, fouling materials are investigated to reveal the mechanism of railway sub-structure deterioration