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How to Topple a Statue Using Science

This is just crazy interesting. And subversive! From Popular Mechanics! Who knew? Closet outside agitators, lol? I thought a minute before doing the repost. We remember what happened to comrade Coronado when someone publicly asked him how he made incendiary devices - back in prison. So wrong. Political persecution for sure.

So, I am just passing this along without encouraging anyone to destroy private or public property. (Wink wink.) ~ alza.
How to Topple a Statue Using Science

Bring that sucker down without anyone getting hurt.

It hasn't been a great past few weeks great past few weeks for statues.

From Bristol, England to Birmingham, Alabama, people all over the world have been grappling with the legacy of racism by tossing their grappling hooks around the heads of problematic monuments.

Should you happen to find yourself near a statue that you decide you no longer like, we asked scientists for the best, safest ways to bring it to the ground without anyone getting hurt—except, of course, for the inanimate racist who's been dead for a century anyway.

The Physical Approach

The force required to pull down a statue isn't as great as you think, says mechanical engineer Scott Holland. Most statues are bronze, using an alloy of 90 percent copper and 10 percent tin and a maximum thickness of 3/16 of an inch. The Statue of Liberty's copper sheeting is only 3/32 of an inch thick, for comparison.

Holland says your average statue of a person tops out at around 3,500 pounds. (FYI: A horse statue is approximately 7,000 pounds.) Meanwhile, the OSHA-mandated upper force limit for horizontal pulling per person is 50 pounds of force—"but that's for working every day," he says, "so you could probably do twice that."

At 100 pounds of force, then, we're talking about a 35-person job to drag the statue, Holland says. But to pull it down, "let's assume twice the force—so you'll need twice as many people." So before you start toppling, you'd better recruit 70 buddies with a bit of muscle.

Now that you have your crew, you'll need the right tools. Holland suggests grabbing a few 4x4 recovery straps, which can be rated to over 32,000 pounds and are far less cumbersome than a chain. Once you're properly equipped, you want to get leverage, Holland says, "so you need to get the straps around the head or the neck [of the statue]."

To break the statue from its base, split into two teams on either side and work in a back-and-forth motion. Most statues are attached to the base by 2 to 3 feet of rebar, so you'll actually be breaking it at the bronze above the rebar—not the rebar itself, says Holland. (That's steel.) "When the U.S. took down that statue of Saddam Hussein, you can see it folds at that spot where the rebar is in the base of it," he says.
Let's say you can't find 70 friends. If you still want to attempt this with a smaller removal squad, you have to weaken the monument itself. That's where temperature comes in.
Yield strength changes a lot with temperature. A 90 percent copper/10 percent tin statue, for example, will have a yield strength at room temperature of 31.4 megapascals—that's compared to 275 MPa for 6061 aluminum—"so structurally," Holland says, "it's not hard to break."

With 35 people, you need to cut the statue's yield strength in half by heating it up. And how do you do that? For a bronze statue, your target temperature is around 450 degrees Celsius, or 842 degrees Fahrenheit. "You could use a butane torch," says Holland, "but it would be much quicker with a propane torch. Those burn hotter. You'll be there for 15 to 20 minutes, but it's a lot easier."
Just make sure you use the proper protective equipment and look to see that nobody is underneath the statue when it falls. That means using a long rope to make sure the first person on the rope is farther away from the statue than the statue is tall. Use this handy Pythagorean triangle calculator to help figure that out.
Read the rest here.  https://www.popularmechanics.com/science/a32870657/remove-statue-science/?fbclid=IwAR0BVhM7HFNwqB_QBExV6ZQNuV2lFb2V27eOIdB5LK5K-1AKpjaf08A8jl8

Shoot! 23.Jun.2020 00:31

alza miento

The photo captions didn't get posted.

The one of beheaded Columbus was taken in Boston. The one of slave trader Edward Colston getting dunked is in Bristol, England.

Criminal Forensic Science 27.Jun.2020 12:26


Science, Bitch!
Science, Bitch!