Cantilever Beam Test
A cantilever beam is excavated in the snow. This can be used as a measure of tensile strength or changes in it.
A standard mechanical cantilever beam loaded only with it's own weight is shown here. (In many engineering tests a single load is applied on the end and increased until the beam fails.)
A cantilever beam test as performed in snow is shown below. No additional load is added, the only weight is from the beam itself. The tensile strength at the top of the beam where it is connected to the rest of the snowpack is a function of the thickness (T) and the length (L) of the beam. The bottom is generally undercut until failure and the length recorded. This must be done relatively quickly so that the snow behaves elastically and has a brittle failure. Slow loading on snow can result in ductile deformation without failure, or prior to failure. (See visco-elastic.)
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