Well, they’ve shut down yet another set of lanes today on the I-94 inbound, as if the first few miles weren’t enough. :mad: :mad: :mad: :mad:
What I’m wanting to know, is why? What type of construction, and what does it help when they cut square sections out of the road? The sections are cut, left for weeks, and then filled in again. What is the point of all this?
It is concrete panel or joint repair and rehabilitation. Concrete pavement is made up of square or rectangular panels. Typical dimensions are 12 feet wide by 15 feet long. They can have cracks form or, with loss of the underlying sand/gravel support, they may rock slightly as traffic passes from one panel to another. (Traffic passing from one panel to the next is called load transfer.) Most often the panels are connected with reinforcement bars (rebar) sunk half in the side of one panel, and the other half in the adjacent panel. This assists with load transfer. Cracks may form from the underlying support (the sand/gravel layer) not being supportive enough, heavier than anticipated loads, the concrete used was a bad mixture, or the concrete simply has reached the end of its design life.
The repair work involves digging out the bad concrete panels. This may involve cutting the concrete with saws if the whole panel is not broken. Otherwise the whole panel is removed back to the existing joints. The underlying base material is checked and, if necessary, dug out, replaced and compacted to make it firm. Then new concrete is poured.
Sometimes the concrete pavement was constructed without the rebar, and later they retrofit it by digging small sections out across the joint boundary between two panels, placing a rebar, and pouring the concrete. This is a case where I wonder why they couldn’t get it right in the first place. 
As to why it takes several weeks, it is most cost effective to finish all of the removal and preparation before pouring any of the concrete.
I see now, that makes more sense. Now that I understand if better, I can just get pissed off at the other drivers instead of the actual construction. 