Some Questions Answered

I've had a few thoughts floating through my head that I haven't really been able to answer but it seems I've found a magazine article that explains some of it. Found here, the article, written by Zach Zorich back in 2005 for Discover Magazine, helped answer the questions, "Who's studying flexible concrete?" and "How much does flexible concrete cost?" With this article and the video I found 2 weeks ago, it seems that, if I want to look into the studies done on flexible concrete, I should look for professor Victor Li of the University of Michigan. He seems to be one of the main Civil Engineers working on this type of project. Also from the article, it was stated that flexible concrete is approximately 3 times more expensive than standard concrete. Standard concrete is somewhere close to $100 for every cubic yard created. That means flexible concrete would be in the $300 range for every cubic yard. To put this into perspective, a single car driveway is usually designed to be 10 feet wide and 18 feet long. Then, on top of that information, the slabs of concrete are designed to be, at a minimum, 4 inches thick. With a bit of math, this driveway uses 2.22 cubic yards of concrete resulting in costs of $222 for standard concrete use and $666 for flexible concrete use. While this doesn't seem like much, think about trying to do this on thousands of miles of roads throughout the country which, due to heavier loads like tractor trailers and hundreds of cars passing over per hour, the cost would be astronomical. But, this is information from almost 11 years ago (hard to think it has been 11 years since 2005) which means that it is entirely possible the Professor Li, along with many other Civil Engineers who may have tasked themselves with studying this relatively new material, were able to reduce the cost of flexible concrete. These were just a couple things I have been thinking about and now have a basis on where to look next.

Carbon Nanotubes and Cement

In class the other day, while working in the library, I found an interesting study done that I was actually curious about (which can be founder here). I was curious about how the use of carbon nanotubes would effect flexible concrete. This conducted test measured multiple different strengths with multiple different forms of carbon nanotubes and was able to show that they actually do increase the strength within a cement mixture, a key part in concrete and flexible concrete. The amazing thing about carbon nanotubes is just how ridiculously small they are. As seen within the study, images were taken of the various forms of nanotubes tested and have to be referenced on the micrometer scale. That's .000001 meters or 1/39360000". Due to their size and tested strengths, they are a material that has one of the highest strength to weight ratios ever recorded. The only issue is that they, currently, can only be made to be extremely short in length, short enough that the nanotubes can still be measured in that micrometer scale. This also leads to an economical issue since the production of these ridiculously small objects tends to be very expensive. Hopefully one day they won't be and who knows what can come of this relatively new material. I'm looking forward to seeing if there is a way to make the nanotubes possible on the economic side in my next bout of research because, as seen in the conducted study, they worked extremely well on the strength side.

Professor Li | University of Michigan

Beginning my research, this was one video that came up. Professor Li of the University of Michigan College of Engineering has been studying bendable concrete for some time now. He has even gone as far as placing test strips on roads to see if it is a feasible replacement to standard concrete. It was very interesting to learn about some other things about flexible concrete. It had never crossed my mind that the steel could rust and expand causing the concrete to crack which is a force that can easily be mitigated by the flexible concrete. I also didn't think that the flexible concrete could fix its cracks with just air and water. This is important considering, in places like Buffalo where the winter weather tears roads apart, pot holes may never be able to form since the water that would fill the cracks could then help fix those cracks.

This video is also helpful in showing how differently standard and flexible concrete act under normal, every-day loading capacities and even how much higher of a load the flexible concrete can take when compared to standard concrete.

Introduction

Hello, welcome to my blog. For this blog I will be discussing some of the research I am doing for my University at Buffalo English 201 paper. For this paper I am looking to research flexible concrete.

Normally, concrete is a mixture of water, sand, small rocks (also known as aggregate), and cement. This mixture remains slightly fluid and allows you to pour it over steel rebar and form it into any shape needed for the structure. When the concrete is loaded with a weight, whether this is a car on a driveway or a house on its foundation, the concrete wants to bend downward which causes the bottom side of the concrete to separate and crack. This is where the rebar comes into play. The rebar takes the tensile loading that causes the concrete to crack. It is fairly easy to imagine how these two different materials act in tensile loading. To imagine concrete, take a granola bar and pull on both ends. Then, to imagine steel rebar, take a piece of string and pull on both ends. You should notice that, when compared, the string takes a lot more force to break than the granola bar. When putting concrete together with steel, a high strength material is created.

For flexible concrete, the aggregate and steel are replaced by high strength fibers and allow for a similar material to be built. The only exception to this is that it will be a much lighter weight material and, possibly, a cheaper and higher strength material. With this paper, I'm hoping to research the feasibility of flexible concrete as a replacement to standard concrete for home foundations, driveways, load-bearing columns, and explore some of its other uses along with exploring its financial feasibility.