Over the river

What were we thinking!?! When we began building roads we soon discovered that we needed bridges. Originally they were rather basic and mostly made of wood or stone. Stone is low maintenance and wood easily replaced, unless you get ridiculous like some of those old railroad trestles; then came the modern era with its huge, steel bridges. Not satisfied with this we began building highways on elevated roadways with all kinds of criss-crossing ramps and steel girder supports. They looked cool. Then they started to fall apart.

Some of the big bridges seem to have anticipated the problem and have staff that maintains the structure, starting at one end and working to the other, then starting all over again. But there seem to be too many elevated structures. There is a whole spaghetti of ramps and roadways in Albany that I drove over for years. I never saw any maintenance going on.

How do they know when the roads are not safe anymore? Well, the dad in the Calvin and Hobbs cartoons seems to have a handle on it. When his son Calvin saw a weight limit sign while crossing a bridge in Dad’s car he asked how they knew what the limit was. Dad told him that they build a bridge first, then drive heavier and heavier trucks over it until it collapses. Then they write down the weight of the last truck to cross safely and rebuild the bridge.

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One of my many jobs over the years involved demonstrating equipment for the removal and maintenance of concrete. We got a call from the maintenance department for the Kingston-Rhinecliff bridge. The pylons that hold the bridge up are constructed of a large concrete column with steel “feet” under the bridge that rest on the columns.

Well it seems that over the years the salt used on the roadway in winter has washed down to where the feet meet the concrete. The concrete is deteriorating. They needed a way to chip away the bad concrete so they could patch things up. The thing I wondered is how long can this go on? Won’t they just run out of a good, flat concrete footing eventually? I guess it would be time to build another bridge then. Oh, and don’t forget to write down the weight of the last truck to cross safely. I hope they remembered to do that with that bridge on the New York Thruway up near Schenectady that collapsed a few years back.

A lot of our structures are slowly crumbling and losing their strength. I can identify with that. The difference is that I have doctors who watch over me. I do have one question.

Why do they keep weighing me?

Bill Abrams resides in Pine Plains; he has chosen not to share the results of his last weigh-in.