# Oobleck for Potholes

From AAAS ScienceNOW:

So-called non-Newtonian fluids are the stars of high school science demonstrations. In one example, an ooey-gooey batter made from corn starch and water oozes like a liquid when moved slowly. But punch it, or run across a giant puddle of it, and it becomes stiff like a solid. Pour it on top of a speaker cone, and the vibrations cause the fluid to stiffen and form strange tendril-like shapes. Now, a group of college students has figured out a new use for the strange stuff: filler for potholes.

Clever! The prototype, from a group Case Western Reserve University undergraduates, consists of a waterproof Kevlar-reinforced pouch filled with shear-thickening fluid that can be simply dropped into a pothole to effect a quick fix. Under its own weight, the fluid is Newtonian and flows to take the shape of its container (i.e. the pothole). But when a car drives over, it thickens in response and supports the weight. Apparently it works very well as a temporary fix, but questions remain about long-term and cold-weather performance.

[Thanks, Alan Dove!]

Silly Putty for Potholes

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### BY Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I write for MAKE, serve as Technical Editor for MAKE magazine, and develop original DIY content for Make: Projects.

### 4 Responses to Oobleck for Potholes

1. The question I’ve seen posted elsewhere – what happens when a car stops on the pothole, and it returns to a Newtonian fluid?

• Nevermind… I was thinking of people running on oobleck, where we have to run to increase the force, and thus, pressure each footfall applies to it so we don’t sink. But a car’s horizontal velocity shouldn’t have an effect on the downward force it applies to the oobleck. Guess I just need my morning coffee. Sorry about that. Carry on.

• I think you were right the first time. A stopped car tire will slowly sink into the hole as far as the bag permits, but that won’t cause any tire/suspension damage.

2. miroslava von schlochbaum on said:

yes “Kevlar-reinforced pouch” but studded tires on a 3 tons of truck optionally loaded with another half ton of load which is braking across it? in anycase, it’s quite an ingenious notion.