About gutters

On Nov 8 I noticed some kind of guides for installing the gutters on Melville Street. I did not know what the purpose of these guides were--I expected that the construction workers would have to install forms and I thought the guides might be there to help position the forms.

On Nov 11 workers were installing the gutters. They did not use any forms at all. Rather they had a gutter machine. It ate concrete from a concrete truck, and it extruded finished gutters. Since the gutters did not sag and lose their shape, the concrete must have been very stiff when it was still wet.

 

Below is a picture from another angle. You can see the gutter being extruded in the lower left. The guides that the workers had installed earlier must tell the machine exactly where it is supposed to be going.

A bunch of workmen were busy smoothing the concrete.

 

If you know more about modern ways of forming concrete, feel free to share what you know.

My guess is that something very similar was happening when the new runways were installed at the airport, and that the machine there was just a much bigger version of the gutter machine.