Research on geotextiles for heavy haul railways

Abstract

Research has been conducted over the last several years on the use of geotextiles for mainline heavy tonnage railroad tracks. A wide range of geotextiles was observed to provide improvements in many short-term applications. However, many of these improvements were not long lasting. For longevity of the application a much greater discrimination between geotextile types, geotextile weight, polymer types, and fiber denier was found to be desirable. Also found important was the necessity to match the geotextile properties with the soils engineering properties and to follow correct construction procedures.Drainage was found to be the most critical aspect for achieving long-term stability in the track structure. Excess moisture within the roadbed was found to reduce the subgrade strength and provide easy access for fine grain soils to foul the open ballast. Proper drainage techniques combined with geotextiles are given special consideration.Conclusions are drawn regarding the desirable attributes that should be specified in preparing quality requirements for geotextiles to be obtained under conditions of competitive tendering. Keywords: geotextiles, synthetic fabric, fabric, railroad, tracks, track support, rehabilitation, soil mechanics.