A model dam on the shaking table
Shaking-table tests were carried
out on a scaled down model of a concrete
gravity dam. (Why?)
The models were 1/30th the size of a real 30 metre high
dam, so they were only one metre tall.
When a scale-model of a structure is made, sometimes materials
different to the real structure are used, as the strength
of the material is also scaled down. These models used a mixture
of plaster, sand and a very fine grained earth to represent
the concrete. To make the model,
the wet mixture was poured into a mould of the dam (Show
Me). When the mixture set hard, the mould was taken off
to reveal the model.
The model was then set up on the shaking-table.
(Show Me). Some extra mass and a tank of water were
set up behind the model (Explain)