Editing Track ballast (section)

== Quantities ==

The quantity of ballast used tends to vary with gauge, with the wider gauges tending to have wider formations, although one report states that for a given load and speed, narrowing the gauge only slightly reduces the quantity of earthwork and ballast needed. The depth of ballast also tends to vary with the density of rail traffic, as faster and heavier traffic requires greater stability. The quantity of ballast also tends to increase over the years as more and more ballast is piled onto an existing roadbed. Some figures from an 1897 report listing requirements for light railways (usually narrower than standard gauge) are:

* first class line – {{convert|60|lb/yd|kg/m|1|abbr=on}} [[Rail profile|rail]] – {{convert|1700|cuyd/mi|m3/km|abbr=on|lk=on}}.
* second class line – {{convert|41.5|lb/yd|kg/m|1|abbr=on}} rail – {{convert|1135|cuyd/mi|m3/km|abbr=on}}.
* third class line – {{convert|30|lb/yd|kg/m|1|abbr=on}} rail – {{convert|600|cuyd/mi|m3/km|abbr=on}}.<ref>{{cite news |url=http://nla.gov.au/nla.news-article3658726 |title=Light Railways. |newspaper=[[The Brisbane Courier]] |date=29 September 1897 |access-date=21 May 2011 |page=5 |publisher=National Library of Australia}}</ref>