How do engineers know that the pillars supporting a bridge can withstand the force of thousands of cars driving over them for decades? How do we know what would happen to that bridge during an earthquake? What about an earthquake in winter?
Buildings, roads and bridges are all designed with a buffer of safety—basically, engineers round up on the numbers, a lot, and design these things to be far more sturdy than they actually have to be. But to make those decisions, they first have to know the physical limits of the materials they're working with. The best way to do that: Take a scaled version of a girder, pillar, or concrete slab and push it past the breaking point. Yes, this is, in fact, as awesome as it sounds.
The Constructed Facilities Laboratory at North Carolina State University is one of the places in the United States where this kind of research happens. In this lab, engineering researchers shake, bend, freeze, and crush the stuff that supports our world. I got to take a tour of this lab back in January, led by lab manager, Greg Lucier.
The videos here will take you through the 4500-square-foot lab and introduce you to the equipment these engineers use—from giant compression machines to something called a "Thermotron environmental chamber."
We'll start with a quick spin around the lab, just to get acquainted with the space. Then, you'll learn how some of the systems you see here work and why they're so important. Read the rest
I love this video of an iceberg collapsing in on itself in Wilhelmina Bay, Antarctica. (Word of warning, the people filming this loved the experience even more than I loved watching it, so much so that you may want to turn your speakers down.)
There are two kinds of icebergs, tabular and non-tabular. The tabular ones are what they sound like, big flat sheets of ice. Non-tabular are different—irregular shapes that become even more irregular as bits and pieces of them melt. Judging by the arched shape this iceberg had taken on, it probably falls into the non-tabular category. Implosion happens when melting weakens key structural support within that shape and bits of the iceberg begin to crash in on itself, accelerating the breakup. Both tabular and non-tabular icebergs and catastrophically fail like this, though.
Another fun iceberg fact: There are six size categories we sort icebergs by. Four of them have pretty predictable names: "Small", "Medium", "Large", and "Very Large". But below "small" are two size categories with a little more whimsy.
Icebergs with a hight of less than 3.3 feet and a length less than 16 feet are called "Growlers".
If the height shorter than 16 feet and the length shorter than 49 feet, then the iceberg is called, adorably, "a Bergy Bit". Yes, that is a technical term.