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Anchor test setup at SKA South Africa Karoo site

Submitter: Marco Drost
Description: During the holiday season, some of us sleep in tents and rely on tent pegs to hold up these light and nimble structures. It can be a frustrating experience to hammer down the pegs into a hard soil. For each situation, there is a specific type of peg to ensure a good night's sleep.

Some of us also use such ground anchors to secure other types of structure. For instance the SKA Mid-Frequency Aperture Array (MFAA) environmental prototypes, which will be placed at the South African SKA site. Some of these prototypes are also light and large like tents, and need good anchoring to ensure their location over time.

Two experienced camping enthusiasts where sent to the site to investigate which type of anchor is best for this case.

The investigation was executed in two phases. First the maximum holding power of each type of anchor was tested by sheer muscle power, in combination with a spring balance. After that, an endurance test setup was assembled and placed near the PAPER array. This setup will be there for several years to see how aspects like corrosion, flooding and creep will influence the different anchoring methods.

Both camping enthusiast concluded that the SKA South Africa soil (compact sand) is hard to penetrate with for instance a screw type of anchor. However, the pin anchor which is hammered into the soil will hold very well. Holding strengths exceeding 150 kg were measured, which allows the safe installation of the environmental prototypes in the near future.
Copyright: ASTRON
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