Concrete Sidewalk Solution

Posted by John B. Kelly

Left: Amherst sidewalk with diagonal joint lines.
Photo: Rob DuBuske

This post is a follow-up to my posting of July 24, Concrete Sidewalk Primer

Some construction workers in Amherst told me about this new stretch of sidewalk, which is laid on a diagonal. I think the main joint line (which runs from the bottom right corner of the photo up and to the left) between the slabs of concrete is wider than necessary, but it was nevertheless a joy to drive over these lines on wheel at a time.

Last weekend, I got a chance to talk to a construction engineer who works for the Connecticut State highway department, and he was intrigued by the idea of diagonal joint lines.

Although not much involved with sidewalk construction these days, he was familiar with the common rationale that I've been hearing everywhere, namely that these "cracks" exist to guide beginning cracks in an invisible direction, thereby preserving the appearance of the sidewalk.

In other words, these "control joint lines" are installed for aesthetic reasons, and if they should inflict suffering on some pedestrians -- wheelchair users, specifically -- why not cut the lines at an angle?

What scares me is that maybe no one has ever asked wheelchair users what kind of sidewalk we would prefer. One word says it all: Smooth.