Open House Day 2: Working in West Town

For day two of the open house events, we decided to visit sites that were in more on our side of town, and also sites that made stuff. Really, the focus was the Prairie Material concrete works. I have been somewhere between appreciative and obsessed with the concrete factory at the corner of Chicago and Halsted for a loooooong time now. Getting to take a tour was really a dream come true!

In the yard area between the silos and the conveyors, they had samples set up. There were a lot of concrete cores, and depending on the density of their aggregates the weight varied considerably. We of course thought of Liam and the brick project that he did for his Materials Science class earlier this semester!

I’m sure if readers haven’t figured out what kind of buildings I’m talking about, this overview of the silos will help. Isn’t it meta that a concrete factory would be made out of … concrete?

Prairie Material is located on the north branch of the Chicago River. This allows materials to be brought by barge. Two barges of materials are brought from the quarry in Joliet every day, and each barge keeps 77 trucks off the roads by transporting so efficiently by water. This energy saving transporation allows Prairie to bid for jobs that require higher environmental standards.

Here’s an empty barge, sitting very high in the river. Right behind it is a full barge, sitting much lower! A clamshell crane unloads aggregate from the barge and puts it into the little train car, which then wheels toward where I was standing to take the photo before unloading the material into a conveyor to take it to the top of the silos.

Aggregate, or rocks of different sizes, weights and properties, are stored in each of the 11 silos. To make a particular kind of concrete, the correct proportions of aggregate are released down via gravity power onto conveyor belts, then brought up to this mixing area. This big mixer mixes the aggregate with cement, which is stored in huge tanks, then it’s put into a truck super fast and brought to a job site. This factory is known (within the concrete production world) for it’s incredible speed.

Command central: this control panel tells which silos are full and supposedly makes it all happen. They were not in production for the day because of the open house, but on a working day if a person like Miles here reached over and flipped a switch, all kinds of concrete production would start to happen.

Can’t get enough of these silos!

Underneath the big row of 11 silos, there is a conveyor room. Each silo has two chutes with gates at the bottom, and that’s how the aggregate dumps out onto the conveyor and goes on to its next spot. The aggregate has to be kept moist or else it can clump and cause problems at the gate.

Hugely interesting! But the tour was finished and it was time to move on. We then rode our bikes to the Ignite Glassworks studio. Glass doesn’t need much introduction, it’s just always so fun to look at.

An unexpected treat there was the view from the roof deck. Not only was there a great view of the Sears/Willis Tower and other skyscrapers, other west side industrial buildings are in view, as well as this really amazing mural in the foreground!