Rapidly melting snow causes rlwy embankment to subside

[bikkuri bahn]

YUBARI, Hokkaido -- Services on a train line here have been seriously disrupted after a massive landslide along a railway embankment, probably due to snowmelt, left part of the line's tracks hanging in the air.

 

According to Hokkaido Railway Co. (JR Hokkaido) officials, the driver of a local train on the JR Sekisho Line reported experiencing "a vertical shake" at around 7:10 a.m. on April 27, when it was passing between Yubari and Shikanotani stations.

 

The landslide, which swept the earth out from under the tracks for some 50 meters, reaching a nearby municipal road, is presumed to have occurred shortly after the train passed by, officials say.

 

http://mainichi.jp/english/english/newsselect/news/20120428p2a00m0na012000c.html

 

[The_Ghan]

That fill is looking pretty loose to me.  I'm surprised the snow isn't factored into the design.

 

Cheers

 

The_Ghan

[miyakoji]

Seems like it's been a rough while for JRH.  There was some kind of budgeting change before that tunnel fire wasn't there?  I remember we were talking here about possible changes in rolling stock maintenance because of that, I wonder if track maintenance could have suffered as well.

[bikkuri bahn]

That fill is looking pretty loose to me.  I'm surprised the snow isn't factored into the design.

 

The winter was especially long and cold this year, and suddenly it got warmer- the snow melted much faster than usual, saturating the ground.  Today it got up to 26C here in Sapporo, the warmest in 14 years for this date.  Extremes in weather have become the norm, it seems.

[The_Ghan]

That fill is looking pretty loose to me.  I'm surprised the snow isn't factored into the design.

 

The winter was especially long and cold this year, and suddenly it got warmer- the snow melted much faster than usual, saturating the ground.  Today it got up to 26C here in Sapporo, the warmest in 14 years for this date.  Extremes in weather have become the norm, it seems.

 

I've been involved with similar sized earth structures for dams and mining here in Australia.  It is normal practice to lay gabions and cover with a geotech fabric in order to both promote drainage and provide some retaining structure.  I'm not an expert - just familiar with experts work.  But I don't see any drainage design in the photo.

 

Cheers

 

The_Ghan

[bikkuri bahn]

It's a minor line that sees few trains a day (just single diesel railcars, I believe).  I doubt JR Hokkaido would have thought about any extensive embankment reinforcement, at least until this incident.

[bikkuri bahn]

Service was restored to the line yesterday, though the affected portion has trains traversing it at under 25km/h.  JR Hokkaido was quoted as saying 214 trains were cancelled by the embankment collapse, with 1400 passengers being affected, which averages out to 6.5 passengers a train.

[The_Ghan]

Clearly they are learning from Sydney's CityRail press releases.

 

Cheers

 

The_Ghan