text

The rock and ice mechanics lab at Lamont-Doherty is led by PIs Heather Savage, Christine McCarthy and Ben Holtzman. We are in the process of growing our lab and building our experimental program. Along with a team of postdocs, undergrads, grads, and longtime staff engineer Ted, we are rehabilitating and revamping some of the old equipment and building new rigs for exciting new experiments on both rock and ice. You can follow along with our progress here.

Friday, 30 September 2011

a library grows at lamont

Today we cleared some counter space and pulled out all the old dusty reference books out of boxes. Need to know anything about metals, alloys, pressure vessels, analog to digital conversion?....we've got it covered! And nice bookends, don't you think? 

Wednesday, 28 September 2011

a gaggle of strain gauges

Today we moved another big step closer to running an experiment by connecting strain gauges to the sample. Ted affixed various kinds of gauges along the business edge of the sample in order to measure strain that is parallel, perpendicular, and at 45 degrees to the frictional surface. The gauges are then soldered to a rainbow of wires that lead to that little green breakout box. Coming from the box are wired connectors that will plug into individual signal conditioners.
Each of 10 signal conditioners below are used to zero-out and amplify the response from the gauges and will then send a voltage output to the computer.
We were getting a little interference from the rainbow of wires and the output connections in the back were hard to reach, so Ted reconfigured it as below, with the strain wires now hiding safely inside the silver mesh tube. Although it looks a bit hectic this way, it works really well.
And "how on earth do we plug all those things into the computer?" you may ask. Well they first get connected to this BNC box. Then the BNC box is connected to a thing called a chassis (more on that later) that is, in turn, connected to a card in the back of the PC.


Thursday, 22 September 2011

a clean, well-lighted place to talk about rocks

Big addition to the lab yesterday: the facilities folks found us a table! I don't know where they found it, but it's new-ish, relatively clean, and can be wheeled around the lab easily. Today I came in to find a cute little plant in the middle of it. Now we have a place to sit around and plan the next step. Since our housecleaning is generally finished, it is time to start rehabilitating the testing machinery. First on the list is that rig in the center back. It is called a "biaxial" friction apparatus because it applies stress on the top and on one side, but there is no confining pressure.

Tuesday, 20 September 2011

a little calibrating

Today was a very productive day. While Ted worked on the strain gauges (they each have to be glued onto the side of the sample and then soldered to wires), I calibrated the LVDT. The box on the left provides an excitation voltage to the LVDT, which is a cylinder with a hollow in the middle. Using that little Schaevitz tool in the foreground, I systematically inserted a core piece into the hollow of the LVDT a half millimeter at a time. With each increment, the LVDT puts out a different voltage, which is measured by the box on the right. I make a plot of distance versus voltage that tells us the calibration factor for our experiments. 
Meanwhile, Heather checked the gauges and put a protective coating on the load cells. We use homemade load cells here, which is unusual I think. We will put one on the side of the sample to measure the horizontal load and one on the top to measure the vertical.


a little outreach

This weekend I volunteered at the Maker Faire in Queens. The event is a big collection of folks interested in science, engineering, do-it-yourself home projects, crafts...the list goes on and on.
Next to the home-still biodiesel guy was Dr. Buckner from Science for Citizens talking about dinosaur teeth and a mastodon fossil that was found here in New York.
Science-Cheerleaders were there, along with Gen-Space (a DIY science lab in Brooklyn), to help kids and adults do some hands-on science experiments.
The project was to extract the DNA from strawberries using everyday household items. Here's a primer on how you can do it at your home!  That's me in the lab coat below.

I also brought some of the rock and mineral samples from the lab for kids to play with.

Friday, 16 September 2011

off-site adventure

This week Heather and I attended a conference for the Southern California Earthquake Center (SCEC), held annually in Palm Springs. I got a gorgeous view of the Grand Canyon during the flight over.
Heather and her colleague presented a poster about earthquakes in the US "triggered" by the 9.0 Tohoku-Oki earthquake.
In between talks and posters, I was able to sneak away to our hotel room to catch up on my journal reading and enjoy the unusually mild Palm Springs weather.

Friday, 9 September 2011

meet the new barista!

Over there behind the chair, next to the presses is a refrigerator. You'll just have to trust me on this.
Today we installed a little coffee station on top of that fridge. Since the campus is far far away from any Starbucks (the horror!!), we need to supply our own. Come 3:00 I am always in serious need of some java. Now we're set. Yay!

Wednesday, 7 September 2011

Resistors 101

So what do you know about resistors? I thought I knew a lot. I knew that they were the little nubby balls connected to two wires and soldered to a circuit board. I knew that they were the squiggly lines on a circuit diagram and are used to control the current in the system. What I didn't know was just how many different kinds (shapes, sizes, range of values) of these things were available. Now I know this all too well.

Today's project was to consolidate the lab's various collections of resistors. Specifically, we were taking the ones in these green metal drawers and putting them with those of matching resistance in these little plastic drawers.
 

Which often meant reading the teeny tiny numbers on each individual resistor in the drawer. I learned that not only do we have resistors for every value from 10 ohms to 10 megaohms, we also have multiple brands and sizes for each.
These three different resistors offer the same resistance but have different size beads (RN55, RN60, and RN65, in case you are curious).
Success!

Tuesday, 6 September 2011

baby steps

My first very small contribution to the lab was to clear off a section of the countertop and designate it the paperwork station. That way we have some clean space to sit and plan, make lists, etc. Seems like a very small change, but oh so important for my mental state.

Monday, 5 September 2011

An Introduction to the lab

So here is our rock mechanics lab. The thing is, the old lab used to be really big and full of lots of stuff. Lots and lots of stuff. They even had some stuff stored over in another building. Before they hired my boss, the University split this old lab into two smaller labs. With her "start up" fund, my boss had the floors and walls redone and new shelves and counter space installed.

When it was time to move back all the old equipment--including the stuff from that other building--there just wasn't enough room. So it was all piled up everywhere. I wish I took a picture of the way it looked a month ago when I first arrived. We have already done a lot of work finding new homes for things. But these pictures will give you the general idea.
 Above is the view from the front. This doesn't even look that bad. The blue and green metal cabinets behind the tool box and the mini drawers above the yellow box on the left are recent installations.
 Here is a view from the back of the lab. That lathe in the foreground is actually up on rollers and may or may not be fully operational. 
 Along the desktop. That section down at the end will eventually be a soldering station. Currently it is just known as the area where I throw the soldering irons (5 so far) when I find them in various parts of the lab.
 This is one of the back rooms, where the high pressure rig is kept. This is what the whole lab looked like one month ago.
And here is the other small back room. That big gray block in the middle is concrete that is connected to the building and the underlying foundation. It will be a great place to do creep experiments or other tests in which you want to reduce any outside vibrations. Right now we just use this as the room where we put the junkiest of the junk that we don't want to deal with any time soon.