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A concrete foundation

The construction industry may not seem like a logical home for a physicist, but Luke Pinkerton believes that a degree in physics has been a big asset in his civil engineering career.

Luke Pinkerton

Two decades ago, when I was studying for my degree in engineering physics, I never imagined I would use it to start a business in the construction industry. I mean, what a stereotypically boring, slow-moving field! And why, after conquering all those advanced maths and physics classes (and doing some really cool research in a zero-gravity environment on NASA's KC135 aircraft) would I want to go into civil engineering? Bear in mind that this is a field that barely requires calculus and is also highly regulated, with prescriptive design codes that limit your creativity. Worse yet, civil engineers are at the bottom of the engineering pay scale (although that still puts them above lots of other professions). What was I thinking?

Sometimes I still ask myself why I chose to work in civil engineering, but whatever my reasons were, I know it was one of the best decisions of my life. My physics background has given me an unusual perspective on the field, one that many of my peers do not have. For example, I don't see things through the limiting framework of the design codes, restrictive as they are. Instead, I'm constantly looking at what is really going on and how I can make it better. Whether it's a building design or a new manufacturing machine design, I love a challenge; something I attribute to a combination of curiosity and a desire to take over the world (just kidding; sort of).

Twisting fibres

Luke Pinkerton's Helix

My company, Helix Steel, produces a twisted steel micro reinforcement that turns brittle concrete into a more flexible composite. Individual pieces of Helix don't look very exciting – they're little twists of metal about as long as the diameter of a US quarter or a 10 pence piece. However, when they are mixed into concrete at a ratio of (typically) less than a dozen kilograms of Helix per cubic metre of concrete, they are strong enough to replace reinforcing bars, or rebar, which is the traditional method of strengthening concrete.

The way Helix does this is based on one of the simplest principles of physics: Hooke's law. Basically, the individual twists of Helix act like torsional/rotational springs in the concrete. In order for concrete with Helix embedded in it to crack, the Helix must untwist. The screw-like shape of the fibres creates a very efficient bond with the concrete, and because the torsional stiffness of the composite material is so high, load is effectively transferred into the Helix even before cracks form in the concrete. Conversely, concrete must crack before rebar carries any load.

In effect, Helix is a marriage between the hi-tech world of aerospace composite materials and low-tech concrete. The result is a lower-cost, better-performing type of concrete. After 15 years of success, a building code approval and a lot of sweat and tears, Helix is now manufactured and sold globally. It is used in applications ranging from high-rise buildings to tunnels and everything in-between, and my goal is to get it into every drop of concrete worldwide; there is no reason not to.

Getting your hands dirty
When I first started working with Helix in the late 1990s as an engineering Master's student at the University of Michigan, the material was made in the lab at a rate of less than a gram per hour by underpaid students using a drill and a pair of pliers. To turn Helix into a commercial technology, I needed to build a machine that could make hundreds of tonnes per hour. This was a seemingly impossible task, one that involved everything from basic mechanics to electronics to operations (and also a lot of patience).

Although I am the president of the company, I spent years building our factory here in Michigan, and yes, I got my hands greasy every day. But it was fun, and I naturally gravitated to the dirtier side of the business because for me it was more comfortable than working in sales. Putting myself out there to sell was not natural for me, and it still isn't. However, I learned quickly that although I enjoyed this refuge of working in the factory, I had to face the challenge of selling if I was ever to see the fruits of my labour.

By late 2003 I still had only one Helix-making machine (built with financing I got from an organization called the National Collegiate Innovators and Inventors Alliance), and I needed sales to keep the company afloat and raise the money required to get us off the ground. As a result, I found myself making cold calls and visiting factories that made things like concrete burial vaults; a far cry from my days of doing research with NASA in Houston! It took me a tremendous amount of energy to do this, given that I had to force myself to be more extroverted and personable than I am naturally. However, because of my confidence in the product, I was able to collect purchase orders for $250 000 worth of Helix. At that point, I had no way to make enough Helix to fill those orders, but I was able to use them to raise the money I needed to expand our operations.

Today, our biggest challenge is pushing the product out of the early adopter phase and into the more mainstream market. This involves all kinds of engineering, physics and business challenges, including sales, new product and manufacturing method development, distribution strategy, logistics, finance and (hardest of all) human resources. Given the amount of regulation in the industry, there are also lobbying challenges, and my latest achievement in this area has been to get approval for Helix under the International Building Code, an important bar for building component acceptability, and one that required extensive testing at independent laboratories.

A case for physics
While I am no expert in all of these areas, I was successful at addressing these challenges in part because my interest and education in physics taught me to ask hard questions and solve problems. Although university tuition fees are going up and the job market is very competitive, I hope that people will not feel that they need to avoid degrees in basic sciences in favour of more "practical" courses. If I had been trained as a civil engineer from the start as an undergraduate, I doubt I would have had the motivation to question the way things are done.

I have not lost touch with my interest in physics, and when I get to the point where I feel that I have done all I can with Helix, I will continue to look for hard problems and attack them. My advice is never to accept someone else's opinion of what can or can't be done; unless, of course, they're talking about a law of physics. Instead, look for problems that you know deep down you can solve, but that you think few others would dare to try. Those are your million-dollar business opportunities. Whether it's figuring out how to sell concrete without rebar or detecting dark matter in the lab (admittedly these are not exactly at the same level, but you get my point), the world is full of challenging problems that invite solutions.

Luke Pinkerton is the president of Helix Steel, which is based in Ann Arbor, Michigan, US.
Email: luke.pinkerton@helixsteel.com



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