Slope or retaining wall failure: geohazard tank model

This is an example of a retaining wall failure; a familiar hazard in ground engineering.
An engineer designed a wall to hold the dry sandy soil whilst houses have been built above.
Examples of this can be seen where roads or railways or other excavations have been built that cut into the land.
Unfortunately, this wall has not been designed correctly and has started to fail. This slope failure is translational in nature and you can see the slip planes that have formed.
Slope failures in (wet) clays and silts tend to fail at shallower angles and be of a 'rotational' or 'flow' type failure.
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