How Much Do You Know About Ballasted Railway Track

The main argument for different railway designs bases on the cost, the installation cost and maintenance cost. Besides the cost, there are still other issues that affect the railway construction, such as environment, the noise, dust and vibration. Or engineering issues, such as space, location, climate and the type of service intended for the railway. There are a wide variety of railway forms and systems incorporating some form of concrete base or support which doesn't need ballast. Almost all of these require less depth of construction than ballasted railway. However, the accuracy of installation must be higher than that needed for ballasted railway. Slab railway will not be adjusted after installation but ballast can be packed to align railway as required.
The ability of ballast to allow railway realignment is one of its most serious weaknesses.  The lateral movement caused by passing trains on curved railway is one of the major causes of maintenance costs added to which is the crushing caused by axle weight and damage due to weather and water. Ballast damage leads to railways "pumping" as a train passes and, eventually, steel rail or railway sleeper damage will occur, to say nothing of the reduced comfort inside the train and the additional wear on rolling stock. Apart from regular repacking or "tamping", ballast will have to be cleaned or replaced every few years. 
Another aspect to the ballasted railway design, is the dust which is caused during installation and as it wears or gets crushed. It does however, offer a useful sound deadening quality. Fixed railway formations using slab railway or a concrete base of some sort do not suffer from such problems. However, the installation of slab railway is reported to cost about 20% more than ballasted railway.  To balance this cost, the maintenance costs have been quoted as reduced by 3 to 5 times that of ballasted railway on a high-speed line in Japan. 
If low levels of use are foreseen, or if low capital cost is a more important requirement, ballasted railway would be the choice. For a heavily used railway, particularly one in a structurally restricted area like a tunnel or viaduct, non-ballasted railway must be the best option on grounds of low maintenance cost and reduced space requirements. However, care must be taken during design and installation to ensure the best out of the system.