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  • Writer's pictureNed Patton

Composites in Infrastructure 2 - the Building Blocks


This is the first of two posts about the materials and product shapes that are starting to be used in a big way in the infrastructure business, mostly commercial buildings, but coming to your new house soon. What you see here are the basics that are needed to make most buildings, bridges, boat docks, highways, tunnels, dams, you name it, pretty much anything commercial, government, or residential.

Most of what you see in pics here is fiberglass in some form or other. With the dropping price of glass fiber and resin, and the increase in the cost of steel and wood for structural framing, fiberglass framing – beams, studs, even door frames – is becoming ubiquitous in the US and in most of the developed world.

One of the first things that was created is fiberglass reinforcing bar (rebar for those of you that know about this stuff). Rebar has traditionally been steel, so with something like a bridge, especially in the Northeast and upper Midwest where they salt the roads in the winter, the steel rebar that is buried inside a concrete bridge rusts and corrodes, leading to having to replace the bridge itself in 15-20 years. With fiberglass rebar, since it doesn’t corrode, the bridge will last for 30 years or more, even in what is a very corrosive environment. Fiberglass is so corrosion resistant that it is eventually the concrete itself that starts to decay, and that process takes a long time, even in the Northeast.


Some other things you see here are I-beams, square and rectangular beams, and even a door frame (top of this post). All of these are fiberglass, and all of them can be used either inside or outside. For commercial buildings where you used to have to have a steel frame for an exterior door and paint it every other year or so, now what is becoming common in new construction is a fiberglass frame and a fiberglass door. Then all you need is stainless steel hardware and the door and frame will last nearly forever – and you don’t even need to paint it. What the manufacturers do is to put a UV and moisture resistant gel coat over the entire surface of the door and frame, making the entire door set have as long a life as the building has.

The I-Beams in the pic to the right are also a dead giveaway to how far the industry has come in developing the basic building blocks of the infrastructure business. Not only are the fiberglass I-Beams as strong as steel, they weigh about a quarter to a third as much as a steel beam the same size. This makes the construction of whatever building they are being put in a much easier task. (I have a photo of a guy carrying two of these on his shoulder for next week’s newsletter – just to make a point.) This is another one of those reasons that people have been moving toward the use of composites in the infrastructure business.


Now that all of the basic building blocks are available and at a cost that is competitive with steel and cheaper than wood, the real benefits of composites in infrastructure are starting to be realized. These include easier (read as less expensive) construction because of their light weight, less man power to install also because of their light weight, extremely long life, and much less attention needing to be paid to corrosion and corrosion inspection.

This last reason that composites win out over steel is critically important for things like bridges. The Golden Gate Bridge in San Francisco was originally painted orange because that was the color of paint that had a rust indicator in its formulation. If you think about San Francisco Bay, there is a fog that moves in most days which keeps everything wet. And it rains a lot here in the Bay Area, so steel has a tendency to rust. And of course, the bridge spans a salt water bay, so the footings of the bridge need to be really well protected. The California Department of Transportation has to constantly monitor that bridge so there are inspections ongoing most of the time on the bridge structure to see where there might be signs of corrosion. And they repaint the bridge with the same orange paint every few years which is quite an undertaking. Of course, it wouldn’t be the Golden Gate Bridge if it were fiberglass, because it wouldn’t have to be orange. And we’re pretty proud of that thing here in the Bay Area, so we pay the price gladly to be able to see the bridge every time we go up to the City.

In the next post in this series I want to continue along this vein a little bit and talk about how each of these composite material basic building blocks is used, primarily in commercial and civil infrastructure projects. One thing to note is that while these building blocks have not made large inroads into residential construction, there is a yet that follows that last statement. In 5-10 years expect to see fiberglass studs and framing at your local Home Depot. It’s just a matter of time.

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