来自MSN1 个月
A Guide to Helical PiersA type of deep foundation system that supports various structures. Helical piers (aka helical piles, screw piles and ground anchors) are screwed into the soil, instead of being buried or rammed in ...
Let us know if you try! Helical antennas aren’t new, but this is an unusual construction. They are popular as satellite antennas because of their polarization characteristics among other things.
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