# is a rebar arch structure a good idea?

I am thinking of building a simple shaded Arch for agriculture. I have an idea of building it with 30 ft sections of rebar that I will bend into a rough art shape. I would then weld rebar perpendicularly to hold each Arch rigidly to the one next to it. I could then put some fabric/membrane to cover and shade the rebar. Overall, it should be very low cost and simple to build. I was thinking of putting rebar every 12 in, but I have no way of knowing if I should increase the frequency or not.

1. For example, How do I calculate the weight that a structure like this can support? Could I hang a fan from the ceiling to push air through the arch. let's say the arch is 12ft high and ~17 ft wide (a bit less than 30 ft edge length). is there a formula for determining the amount of deflection?

a. what thickness of rebar should be used?

b. how frequently should rebar arches be built? ie spacing between arches.

2. If I were to have a tree fall on it, would animals or items inside be safe?

3. Is it okay to have a structure that's fairly flexible? I imagine it would move around quite a bit, but as long as it's anchored into the foundation....is that okay?

4. is this just a bad idea?

Totally an experimental thing here so all ideas and criticisms are welcome! here's a quick pic of what i am thinking (minus the lateral pieces of rebar to prevent the arches from just falling over :P :

• Compute the force of wind with a pressure change and tie it down well. A tree, comes in many sizes. Commented Aug 24, 2022 at 4:12
• will the ridges on the rebar makes holes in the membrane easily over time due to wind moving the membrane? Commented Aug 24, 2022 at 7:00
• No, It's way too heavy, expensive, and flimsy. You can buy kits made of cheap tubing for this. They would be 1/4 the weight and 1/2 the cost, and come with all the connectors, door, and ventilation options. The shade fabric can provide most of the lateral support, you only need a few longerons to support the structure enough to get the fabric on it. farmplasticsupply.com/shade-cloth/shade-cloth-black-40 Commented Aug 24, 2022 at 9:07
• "If I were to have a tree fall on it, would animals or items inside be safe?" Even a properly constructed warehouse might not be safe. Maybe you should deal with the trees if you are expecting them to fall over. Commented Aug 24, 2022 at 14:16