requirements:
- quick to erect
- cheap materials
- hard to move
Landscaping boulder. You could probably get it delivered.
200L water barrel/tank. Though getting the water into it might be more challenging, depending on location.
A 4"x4" fence post and anchor bracket and concrete anchors, you’ll need a hammer drill to drill the holes for the anchors.
We stan tactical urbanism
4.5" PVC pipe, premixed concrete bag, yellow spray paint.
The hardest part will be breaking through the asphalt and down a couple feet for anchoring.
Hole pipe concrete,
Giant rock
IBC container a lot of water
Get a cheap plastic form- a large plastic plant pot would work well. Line with tinfoil or plastic wrap. Cut a large hole in the bottom of the pot and the tinfoil. Turn it upside down in the spot you want the bollard. Fill with quick-set concrete. When the concrete is set, take the pot with you so you can make more, the foil should keep it from sticking. If you can work out a way to get some metal wire into the concrete form before you pour, it’ll be much stronger.
Downsides to this could be getting enough concrete and water to the site- shit is heavy. Also, while it should be set in an hour or two, getting knocked by a car right away might kill it.
I looked it up and an 80 pound bag of concrete needs about 3L of water. That all seems doable.
Anyone know how long it would take to set?
Make sure you get fast-setting concrete. It’s the difference between the time being about an hour vs about a day.
I would expect it to be set enough that you could remove the form after a half hour to an hour
Have you looked into land mines?
Believe me I have thought about figuring out a way to make a tire shredder that won’t trigger for even the heaviest e-bike, but would for cars. Don’t think it’s worth the risk. Primary goal is not to hurt anyone.
Find the biggest plastic tub at a home improvement store
8-10 bags of concrete
Place container, fill with concrete, water appropriately.
Preferably do this in the early evening so it has time to cure over night