I was walking down a residential street in Fredericksburg, VA today. I noticed a strange pattern with the sidewalk. In regular intervals (about every 30 feet), a small section of the cement was swapped out for dirt. The dirt was fine gravel, not like the regular dirt you’d expect to find underneath a sidewalk. The dirt patches stretched across the sidewalk, not just where the tree box would go, and were about two feet wide. Except for these dirt patches, the sidewalk looked relatively new. No cracks or buckling anything. The whole street was like this. I counted twenty five patches in my little walking tour of the town.
Can someone come up with a WAG for what this is all about? I’m afraid I won’t fall asleep until I find the answer. Thanks.
Concrete expands and contracts with temperature changes. If you have a long slab of concrete, it will eventually crack. That’s why people put in “control joints”. An alternative to that would be the patches you’re describing. 30 feet is a bit much, but I don’t know what thickness the concrete in the sidewalk is.
Sounds like the filler the gas company used in my neighborhood last year, on the sections of sidewalk they took out to lay new gas lines, and before new concrete was put down.
