This article is about a kind of landslide. For the place in Cornwall, see Washaway, Cornwall.
A washaway is a particular kind of landslide that can affect man-made structures such as cuttings, embankments and bridges. They are thus a hazard to railways and road traffic.
Flood damage to rail track in Queensland, Australia, showing complete washaway leaving rails suspended
The biggest danger with washaways is that they may be difficult to spot in time to stop short of the point where one falls over the edge and/or into the water where one may drown.
An embankment that is washed away can be repaired or restored by replacing the washed away earth, which is necessarily large because embankments have a gentle slope.
A quicker method is to replace the washed out earth with a criss-cross structure of timber steepers called a pigsty which is only slightly wider than the track itself. The pigsty has alternating layers of transverse and longitudinal layers of these sleepers, which contains a lot of air which saves weight.[1][2] Steel and concrete sleepers are not necessarily suitable for this purpose as they are either not square or fragile.
The sleepers in the pigsty can be reused when the washaway is fully repaired. Rails can substitute for the sleepers. The hollow space inside the pigsty should be able to act as a culvert.[3]
Warning devicesedit
A mechanical railway signal that is normally "green" can be put to "red" if a link in the pulling wire is disengaged by a slump of the earth beneath.
An electrical railway signal that is normally green can be put to red if a contact is opened circuited by a slump of the earth beneath. One side of contact might be attached to the sleepers, while the other side is buried in the ballast beneath. To protect against a false feed keeping the warning signal green, the circuit should be double cut so that false feeds will connect positive to negative and blow a fuse, forcing the warning signal to red. A similar setup might be used to protect bridges likely to be hit by ship collisions, as with the 1993 Big Bayou Canot train wreck.
27 September 1923 – near Glenrock, Wyoming - a bridge over Coal Creek was washed away and a passenger train derailed, killing 30 of the train's 66 passengers.
24 December 1953 - Tangiwai disaster - lahar caused bridge washaway; train thrown into river; 151 killed.
^"A Washaway on the Northampton Railway". Sunday Times (Perth, WA : 1902 - 1954). Perth, WA: National Library of Australia. 12 July 1925. p. 13. Retrieved 9 September 2011.
washaway, this, article, about, kind, landslide, place, cornwall, cornwall, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, s. This article is about a kind of landslide For the place in Cornwall see Washaway Cornwall This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Washaway news newspapers books scholar JSTOR March 2018 Learn how and when to remove this template message A washaway is a particular kind of landslide that can affect man made structures such as cuttings embankments and bridges They are thus a hazard to railways and road traffic Flood damage to rail track in Queensland Australia showing complete washaway leaving rails suspendedThe biggest danger with washaways is that they may be difficult to spot in time to stop short of the point where one falls over the edge and or into the water where one may drown Contents 1 Repairs 2 Warning devices 3 Accidents 3 1 Cause unclear 4 See also 5 ReferencesRepairs editAn embankment that is washed away can be repaired or restored by replacing the washed away earth which is necessarily large because embankments have a gentle slope A quicker method is to replace the washed out earth with a criss cross structure of timber steepers called a pigsty which is only slightly wider than the track itself The pigsty has alternating layers of transverse and longitudinal layers of these sleepers which contains a lot of air which saves weight 1 2 Steel and concrete sleepers are not necessarily suitable for this purpose as they are either not square or fragile The sleepers in the pigsty can be reused when the washaway is fully repaired Rails can substitute for the sleepers The hollow space inside the pigsty should be able to act as a culvert 3 Warning devices editA mechanical railway signal that is normally green can be put to red if a link in the pulling wire is disengaged by a slump of the earth beneath An electrical railway signal that is normally green can be put to red if a contact is opened circuited by a slump of the earth beneath One side of contact might be attached to the sleepers while the other side is buried in the ballast beneath To protect against a false feed keeping the warning signal green the circuit should be double cut so that false feeds will connect positive to negative and blow a fuse forcing the warning signal to red A similar setup might be used to protect bridges likely to be hit by ship collisions as with the 1993 Big Bayou Canot train wreck Accidents editRailway accidents involving bridge washaways include nbsp 27 September 1923 near Glenrock Wyoming a bridge over Coal Creek was washed away and a passenger train derailed killing 30 of the train s 66 passengers nbsp 24 December 1953 Tangiwai disaster lahar caused bridge washaway train thrown into river 151 killed nbsp 1974 Crystal Brook South Australia train thrown into river after washaway collapses bridge nbsp 1993 114 perished in a passenger train that plunged into a river after floods washaway a bridge at Ngai Ndethya nbsp 29 October 2005 Veligonda train disaster 114 killed nbsp November 2011 Feroleto Marcellinara Italy 4 Cause unclear edit nbsp Peruman railway accident 1988 105 killedSee also editList of rail accidents WashoutReferences edit A Washaway on the Northampton Railway Sunday Times Perth WA 1902 1954 Perth WA National Library of Australia 12 July 1925 p 13 Retrieved 9 September 2011 THE WASHAWAYS Geraldton Guardian WA 1906 1928 WA National Library of Australia 14 March 1925 p 4 Retrieved 9 September 2011 WILUNA FOOD SHORTAGE Western Mail Perth WA 1885 1954 Perth WA National Library of Australia 5 April 1934 p 18 Retrieved 9 September 2011 Today s Railway Europe 213 pg 55 Retrieved from https en wikipedia org w index php title Washaway amp oldid 1212384854, wikipedia, wiki, book, books, library,
