ABSTRACT
Railway subgrade is particularly important in ensuring that track quality reaches the standard necessary for the safe and comfortable operation of trains. Railway authorities make serious efforts to improve passenger comfort. These efforts, however, concentrate usually on track superstructure (rails, sleepers, ballast, subballast) (see Figure 7.1) and often disregard the fact that many problems appearing at the track superstructure level are traceable to the subgrade, rather than to the superstructure.
