1 December 2014

Landslides in the Movies Part 2: The Railway Children (1970)

Posted by Dave Petley

The Railway Children – Landslides in the Movies Part 2

This is Part 2 in my new series on Landslides in the Movies.  Part 1 is here.  The 1970 movie The Railway Children, which was based on a novel of the same name by Edith Nesbit, stars a very young Jenny Agutter.  Probably the most famous scene in this film occurs when a landslide blocks the railway line at a time when a train is approaching.  The three children run up the line to flag down the approaching train, thus preventing a disaster.  This scenario is far from impossible – indeed I have featured landslide-induced derailings of trains on many occasions on this blog, and some of them do indeed have catastrophic consequences.

The landslide scene in the film is shown in this sequence on Youtube:

If nothing else it makes you realise how far special effects have come in the last 45 years.  The movement starts as a translational slide – note how the trees remain perfectly upright as they displace – although the movement of the trees whilst the grass around them remains static is quite amusing in some ways.  A really nice element is that the landslide occurs on a cut slope that clearly has an inadequate retaining structure at the toe – it looks like poor engineering by the construction crew to me.  The should never have expected to retain a slope of this size with old railway sleepers.  In addition, the way that the wooden posts topple onto the line suggests that they had very shallow foundations – surely a recipe for disaster:

 

The Railway Children

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It is this poor engineering that probably accounts for the collapse on a beautiful sunny day and in a dry condition (note the dust that is kicked up by the collapse at various points).  The boulders on the line at this point is a nice touch, suggesting some precursory deformation..  Of course the sequencing of the failure is a little odd, in that the upslope section moves before there is much deformation in the retaining structure – there is clearly a complex process at work here.

The Railway Children

The post-failure landslide

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I’m not sure that the film crew managed to depict the post-failure landslide scar particularly well – the deformation at the start suggests that the scar should extend right up the slope.

Finally, I think that the children need to study natural hazards at school, given that they diagnose the event as an earthquake.