Concrete stalactites
June 3, 2010
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| From my photo album; Illinois State University |
Under this plaza is constant leakage, a problem that was not even solved by the… interesting… canopy structure. Each day I go up the stairs to the plaza and get a close look at some concrete stalactites that form where water makes it through cracks to the long walkway below.
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| From my photo album; Beautiful Evidence |
The walkway has white and brown stalactites. My guess would be this one is stained by rust from re-bar.
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| From Beautiful Evidence |
People reach up and break them off; it’s interesting how quickly they re-form. No corresponding stalagmites can form because the water falls where people walk.
Categories: Uncategorized
Acid rain. The more acid, the quicker the stalactites form. Yeah, the reddish-brown color looks like iron oxide. I hope the bridge maintenance people are watching that as closely as you are—you’re making a good case that the thing is corroding away very rapidly.
The Lincoln Memorial in Washington, D.C., was built originally about two stories up off the level of the swamp—they had to go back and push the foundation pillars down to bedrock to stabilize it. The marble walkway from the Reflecting Pool to the marble stairs of the Memorial itself create a cave underneath.
And, since the Memorial opened in the FDR years, some very nice stalactites and stalagmites have formed. The National Park Service does tours in the summer months—you also get to see graffiti left by the workers lampooning their boss. If you’re going, check it out.
In Washington, as the rains got more acid, the growth of the columns increased measurably. Cleaner air in the American Midwest means less acid rain in D.C., and the growth has slowed a bit in recent years.
Cool observation. Call your road or street department. Seriously.