Bamboo Reinforced Concrete

Bamboo is a grass. That's a hard concept for me because some bamboo stalks are 40 feet tall. Bamboo is also composed of many different species in different countries. Some are short, some are tall. Some green, some black, some other colors as well. Pandas eat it. Bamboo is great stuff, apparently.

So imagine you are building a flagpole 40 feet tall. You will have a lot of bending forces at your base. You would want to use a material that had high compressive and tensile strength to meet the moment requirement. You would want to make sure that you could resist the wind from any direction. Nature already took a look at the problem and came up with bamboo.

We can use bamboo in all kinds of applications that mother nature didn't intend, like tension reinforcing in concrete beams. It even has ridges on the outside that prevent bond slip. It's extremely high tensile strength can rival conventional steel reinforcing. For anyone looking to lower the cost of their steel reinforcing budget, bamboo might be a good alternative.

Now for the issues...
1) you still need to tie it up, so labor costs remain high
2) it's not code approved for reinforced concrete, so you'll have to design as unreinforced
3) it's quite expensive if supplies are short in your region
4) you'll need to keep it dry and insect free

But hey, if you are looking for an alternative and green building material, I think combining bamboo reinforcing with other proven options like ICF construction, high fly ash content concrete, and other bamboo/sustainable products throughout would gain a lot of respect in the design world. Bamboo reinforcing is completely accepted in certain parts of Asia, so there is a lot of information about it already. See this for a very well done thesis by Leena Khare at UTA regarding bamboo reinforcing, with test data. See this for other examples of natural fiber reinforcement.

Now, bamboo is getting a lot of good press right now because of it's environmentally friendly properties. It grows superfast and can generally replace any conventional building material, as long as it stays dry and insect free. But be careful if you are considering using bamboo that you only select sustainably farmed products, because we don't want to lose more panda habitat.