How Quicksand Causes Dam Failures

In civil engineering, quicksand is more than just a puddle of mud! The "quick condition" occurs when seepage reduces the effective stress of a soil. This can lead to some dangerous conditions, especially if the seepage causes piping erosion to occur at a dam. Thanks for watching!
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[@jsal7666]

This video is so good, *soil* subscribe to your channel.

[@clonewarrior1999]

J Sal What?

[@AnthonyRagus]

J Sal ಠ_ಠ

[@catcrisst5277]

"So i'll

[@MajesticDemonLord]

Wow. You really had to dig deep for that pun.

[@cuppa.j0o]

J Sal i’m soilscribing to you

[@ThisOldTony]

i blame science (& you by extension) for the lack of quicksand plot devices in today's television programming.

[@PracticalEngineeringChannel]

My life's greatest achievement

[@Bird_Dog00]

Ah, Hollywood quicksand. aka, how an object that floats on water just fine, suddenly sinks in a fluid much denser than water... The only people whom I would expect to sink in quicksand are screenwriters and producers...

[@HPD1171]

there are still tar pits which have the benefit of not only trapping you from being able to move but you also sink since tar like most petroleum based compounds is less dense then water so animals being made mostly of water simply sink while not being able to move to get out. I am not sure why they aren't used as lot devices more often as they are truly terrifying and ARE a death sentence if you have no help to get out. thought there is the problem that they are too viscous to be used in movies as the movement is so slow that you would need a scene that is several hours or even a couple days depending on the viscosity to get the point across so not the most practical.

[@EebstertheGreat]

@@HPD1171 As far as I am aware, there is no record of a human ever getting stuck and dying in a tar pit. The remains of a single ancient woman were found in the La Brea tar pits, but it is believed that she was buried intentionally. They seem to pose a much greater threat to quadrupeds.

[@kvakerbillduck9500]

Indy 4 was not good for you? But i must admit princes bride is way way better

[@RealEngineering]

Fascinating stuff. Could see myself getting into soil mechanics

[@saitenotoshuitsnaini]

Wait. How could the seepage water possibly goes up?

[@syntheovaldy5173]

@@guyfriends1843 ???

[@zombieregime]

It is a deep subject, but the basics can be compressed into a manageable size. This video just scratches the surface, the subject can expand layer by layer.... ....Ok ill stop. Of course im fun at parties. Why do you ask?

[@Abcwhatever]

Now that it's been three years, did you get into it?

[@shubhamraj25]

@@Abcwhatever lol

[@PracticalEngineeringChannel]

Leave a dam comment and let me know what you think!

[@unvergebeneid]

You dam well, know what we think!

[@brozach1394]

Would you be able to achieve a similar effect to the "cutoff wall" by making the base of the dam longer? It obviously wouldn't be as efficient, but would it work?

[@jevaikramullah8798]

Practical Engineering hi grady great video as always ,could you make a video about ground vaccum and how it reduced water ,thanks before and sorry for my bad english

[@TheBrokenLife]

I'll be dammed if I do, sir!

[@cojawfee]

Where can I get some dam bait?

[@miniman3112]

"Engineers generally try to avoid building civil structures out of liquids." :D

[@gennadyreshetnikov5948]

True story!

[@stratosoundvox]

Well, concrete, technically...

[@Zheeraffa1]

Well, they let it set and become a solid first, technically...

[@athenseed6041]

it isn't a solid when set

[@ZilogBob]

Only a real engineer would say that.

[@RandallStephens397]

@3:16 "Engineers generally try to avoid building civil structures out of liquids" [citation needed]

[@zanmerd3033]

Water makes soil liquidy, so engineers try to avoid such areas.

[@wacky.racoon]

I also need a citation for this

[@exhumedlegume8870]

Concrete: Am I a joke to you?

[@stevengiallourakis5816]

Not sure where to leave this comment. I just had surgery for my 4th cancer and i found your channel while i was in the hospital. It has been the perfect thing to help get through this. I am about to graduate with my degree in Applied Mathematics and i love engineering. The demonstrations you do are great and i have really enjoyed watching them. I know its something that most patients might necessarily find entertaining while in the hospital, but i did lol. So thank you friend! Keep up the great work!

[@poster99999999]

Great video! However I felt like it was only the introduction. I was hoping you were going to spend a bit more time on the model and the various conditions or examples.

[@mspeir]

Agreed!

[@moritzkockritz5710]

poster99999999 yeah, I was a little surprised when the outro started

[@cantsolvesudokus]

me too, think he could have build a cutoff wall on the new model and have shown the difference between failure and a stable dam.

[@mrreymundo5383]

I too would have enjoyed more discussion of mitigation techniques, and some demonstrations of those techniques. Also some animations of actual dam failures and their causes would have been great.

[@TheForcedinductn]

Same.

[@theKashConnoisseur]

Practical Engineering: Where you learn more in a 5 minute video than you did in an entire semester of classes.

[@thaton3guy100]

The Kush Connoisseur you must be doing something wrong in your class then

[@theKashConnoisseur]

Yeah joe, it's definitely got nothing to do with the quality of the instructors.

[@suchaccountwow4858]

The Kush Connoisseur But dont blame it all on the instructors tho. No matter how good the instructor is if you still foolin around it will be the same.

[@thatjared4303]

I have to say that my teacher, talked about Donald Trump all semester instead of teaching the subject. The only way i do learn is by watching videos like this.

[@theKashConnoisseur]

@Such Account Wow No matter how studious the student is, they cannot learn if the teacher doesn't teach.

[@wolfbd5950]

3:16 "Engineers generally try to avoid building civil structures out of liquids" is the best sentence I've heard this year.

[@ibtgb2]

These videos actually really help. I'm a general contractor so it's nice having at least a basic understanding of these things when I'm working with civil and soils engineers or when we run into problems in a job.

[@MegaJonSA]

Greetings from South Africa. I'm a recently graduated civil engineer. I remember learning about this at university and manually calculating flow rates by drawing flow nets. It's great that you're making these concepts more understandable to the general public and hopefully, in doing so, inspiring some young minds while you're at it. Great work!

[@Orsan_]

This is absolutely fantastic! As a civil engineering student myself in a land full of sub-soil water, I get really excited about this kind of videos analizing soil mechanics failures general,because we don't tend to visualize the phenomena this precisely. You are an inspiration and a great source of knowledge. Keep going! Hopefully, if someday I get to be a teacher, I'll make my students understad what they're learning through this kind of amazing demonstrations. Greetings from Mexico!

[@thefjk]

"seabitch"

[@raysilins6326]

That is exactly what I thought

[@justindie7543]

led by captain Theon Greyjoy

[@stevewalston7089]

You beat me to it ...

[@lexibigcheese]

that's me.

[@alephkasai9384]

What is he actually saying

[@TheOrangeAngle]

Dam that was a good video

[@Yonatan24]

*_Thlake you :)_*

[@colonelstriker2519]

Did you two just

[@Yonatan24]

Make horrible puns? Yes.

[@Cynyr]

I think you meant it was a great dam video :)

[@phuturephunk]

OH YOU!

[@joanalbertmirallespascual3606]

"Engineers generally try to avoid building civil structures out of liquids." That's what water benders are for.

[@MaximKretsch]

No, that's what ground freezing is for. :-)

[@cryptfire3158]

I'm guessing "water bender" is from the same movie i watched last night. "The last air bender"

[@blackfox2885]

@@cryptfire3158 That movie doesn't exist. Watch the show it's much better.

[@edwardteach3000]

@@cryptfire3158 Movie? What movie? The never made an ATLA movie!

[@cryptfire3158]

@@edwardteach3000 i watched the last air bender on netflix, it's probably still there. In the movie, the kid comes out of frozen state like 500 years later, he has a bunch of powers, there are only pockets of people who can control elements.

[@Mortumnus]

That's a quality video. I wish there was more channels like this on youtube.

[@WonderfulBoness]

Mortumnus does someone know anyone like him on yt

[@feynstein1004]

For physics, PBS Space Time is definitely the best. And Kurzgesagt is good for science in general. Don't know about others.

[@asdfghyter]

There are actually many channels like this on youtube. The difficult thing is to find them.

[@lontongtepungroti2777]

3blue1brown, welch lab, real engineering

[@saketshelke5912]

There's Vsauce, Physics Girl,Simone Giertz etc

[@Geolojas]

Nice! Engineering geologist here, and that was one of the best descriptions of liquefaction I've ever seen. Subscribed!

[@ramsaimaruti4923]

Saw this channel for the first time. Great video and accurate description. To prevent piping, along with cut-off walls/ sheet piles, inverted filters are used too. Inverted filters are the ones with coarse grained on the top and fine grained on the bottom. With increase in surcharge on the d/s side, the critical condition of hydraulic gradient is hard to occur

[@Bird_Dog00]

That got me thinking. Could you mitigate the effects of piping by one of these measures? -driving piles deep into the ground below the dam -excavating deeper and filling the ground below the dam with a mix of soil, gravel and larger rocks -injecting concrete into the ground below the dam

[@HighFidelityFox]

This is litteraly the best channel ever. Complicated things explained in less then 20 minutes with visuals? Better than paid classes.

[@Fwumiko]

What? I wanted to see more of the model in detail with technical explanations!

[@mhhuusko]

Yeah, a slowed more thorough explanation of the mechanics instead of just short jumpcuts.

[@felixbade2879]

Yeah! More demo, less talking face, please! The talking itself is great, but I can’t concentrate when the visuals are gone. I could watch those demo model clips like 20 time without getting bored.

[@AV1461]

My thoughts exactly. I was waiting for a case by case demonstration with time-lapse sequences or so.

[@TomJakobW]

Koishi Komeiji it's quite a fine "line" (well, it's actually continuous, you could always increase the depth a bit and a bit more); popular science or in-depth science. This video could be 2 hours long with formulas and simulations (I would love that, honestly), but that would change the target audience. It's basically the difficult situation for a content creator to decide, how much to "dumb down" but still keep it interesting and scientifically correct. But still I agree with you, I want more, too.

[@AV1461]

That's not quite the point. The thing is that he seems to have got a bunch of awesome footage, but none of the experiments were presented from end to end. Maybe they're on another video. I personally was waiting for the point were he would stop speaking and let the experiment run. But you're right when you say that it's tough to produce a 5min video with everything necessary.

[@keegan707]

Your build and use of dye makes it really easy to see exactly what is happening. Thank you, your awesome.

[@mute8s]

Grady if you ever become a super villain you need to call yourself "The Hydraulic Gradient" get it? Because your name is Grady.... Dam it seemed more funny in my head... :) Anyhow keep up the good work.

[@TheMrblessed]

i laughed; so, it was kinda funny!

[@feynstein1004]

Take your like and get outta here

[@y0h0nk27]

@@feynstein1004 but why?

[@jeffreyquinn3820]

@@feynstein1004 Dammed if you do, dammed if you don't.

[@feynstein1004]

@Jeffrey Quinn Hah

[@Lillireify]

Had my teachers shown me your videos during my studies... Nobody would fail their classes :) your videos are not only very informative, but also extremely interesting and easy to understand :) keep up your amazing work!

[@volvok7749]

Even among YT channels dedicated to science the quality of your content stands out. Thank you very much!

[@Tiandesta]

Currently im majoring in hydrology engineering on campus. This video is so helpful for me to understand about seepage. Thank you so much you dont know how much it helps.

[@montykoolaid]

I seriously hate seepage. Ruins my underwear.

[@lescovar693]

Excuse me what the fuck

[@anitadervishi3807]

Hahaha The first time i heard him say it i thought he said "sea bitch"... 🙉

[@M4xxey]

@@anitadervishi3807 i had to come to the comments to stop hearing "sea bitch"...

[@blahblahblahblah2837]

3:56

[@Agaetis181]

@@lescovar693 hey don't be racist

[@gustavfranklin]

your videos could easily be 20-30 minutes! they're a joy to watch and I ALWAYS learn something new. thank you!

[@ElNeroDiablo]

This video was good. It was dam good! I love how practical demonstrations such as model actually give you physical and easily seen information about the situation being modeled! :D

[@bullymaguire793]

Every Engineering college in this world should demonstrate in this particular way. In india, our college are just making us memorise things without understanding how things are actually happening. Great video.👍

[@smurfendrek4791]

Amazing video, your demonstrations really make this stick with you forever, instead of it just being some formulas you forget.

[@ImOblivious]

Great video. I'm really glad your channel exists for this engineering info. On a side note, you're the only blue apron sponsored channel I've seen actually cook the meal on camera as part of the plug, so props to you for that too.

[@BakerCountyTrashPickup]

Dam, you must be under a lot of pressure.

[@MateusSponch]

Man, I love your videos. I like that you put formulas and we can understand it easily this way. I just wish that video were longer. You could show, for example, dams that failed because of this effect. Thanks for sharing information!

[@calyodelphi124]

That outro suddenly coming up after only a couple of minutes kinda caught me off-guard. It felt like the video ended just as you were in the middle of giving the lesson about this phenomenon. D: I'd be interested to know how quicksand and liquefaction poses dangers to infrastructure and just structures in general, particularly in seismically active areas like the San Francisco and San Jose Bay Area where land has been reclaimed or even outright built using soil fill, as well as the considerations that civil engineers must make when designing for infrastructure and structures in such areas.

[@Renegade30]

liquefaction is a major concern for civil engineers. It can be helped in a number of ways, 1. Avoid saturation of the soil by providing surface drainage or dewatering pumps 2. Create what's called a floating structure that is neutrally buoyant with the soil (usually by making a large basement) 3. Allow relief of soil pore water pressure through some mechanism such as an underground drain These issues are well known and only really an issue in poorer countries where lack of maintenance, shortcuts or corruption occurs.

[@calyodelphi124]

Although these issues are well known, they can still affect more economically developed regions as well. Particularly in areas that haven't been updated with infrastructure retrofits to solve these issues. Especially if it's a region that has a tendency to either neglect or conveniently forget about (or simply can't afford) infrastructure maintenance, upkeep, and replacement, until it just decays to the point where it fails outright and absolutely must be replaced.

[@Ktulu789]

Calyo, I felt that the video was short too. I think that he took more time building the model than showing it's effects and behaviours. For one thing, the building "time lapse" seems longer than the demonstration footage xD

[@nuttynut242]

All soil liquefy if you shake hard enough. However you can do stuff to the soil to make it more resistant to liquefaction. Ground improvement like jet grouting to increase the overall shear strength of soil is one method. For land reclamation projects, the use of a correctly graded soil followed by sufficient degree of consolidation is one way of dealing with liquefaction risks during a designed seismic event.

[@nuttynut242]

@@Renegade30 Longterm mass dewatering cause other problems mate. Don't do it mate. The other 2 ways you mentioned are methods to deal with settlement and consolidation not liquefaction.

[@jeeee3f]

MUCH better into videos and audio than it used to be. Keep up the good work

[@Fred_uyz]

"engineers generally try avoid build civil structures out of liquids" i'd say thats an understatement

[@YTBKd]

You got me all excited with the clear explanation and the beautiful model of the dam and Bam!! The video ends all of a sudden!!

[@YouPlague]

I'd love to see longer footage of the model, possibly the whole process.

[@andrewblack7852]

My father was an engineer. Your videos are wonderful. Articulate and concise. I’d love to see a video that details more methods to overcome seepage and piping in dams.

[@GuyNamedSean]

This is a great way to start my day.

[@leeeric6626]

a civil engineering student here !it is a great channel for me !

[@movingheadmau8128]

wow your videos are very high quality and also very informational thx for sharing! :)

[@steveno0007]

Thank you for putting so much effort to make regular people understand these concepts.

[@Taytyaaytyat]

"Engineers generally try to avoid building civil structures out of liquids" LOL!

[@diwakarkumar7407]

I'm an an engieneer from India...and I really like this video .. looking forward to more videos of soil mechanics

[@MordecaiSumarai]

I wish our dams here in South Africa had more water in them.

[@MarktheRude]

Well you could fill those reservois with communist; they're not human but they are still made out of around 60% of water.

[@halimceria]

but communist is red. no one want to drink red water. they all want aqua-blue capitalistic democratic water.

[@TheUserid82]

Bennie Pretorius perfect time to enlarge the reservoirs when the water is low to get normal equipment in. Even if you make them so deep you can't get flow from them they still let water seep into the ground to recharge the ground water. More capacity means when you do get rain more is captured and not lost out to sea.

[@TheIndogamer]

Deep.

[@Marmocet]

Reverse osmosis desalination plants powered by a nuclear reactor can deliver huge volumes of fresh water for hundreths of a cent per liter and they can run almost continuously for at least half a century. They're a good solution if water shortages are chronic and you live somewhere where people are capable of maintaining infrastructure.

[@IAMCUBEMAN]

The animations are much higher quality since last time I watched a video from you. Top notch

[@elitegamer468]

First quick, think of somehting funny... . . . Dam failure is what my parents call me. Edit: wow internet engineering man likes me now.

[@OutOfNamesToChoose]

I still get seepage after two shakes :(

[@jogodeplanilha]

lol: internet engineering man

[@rudyanggara]

this man explained everything in one semester for five minutes (sorry for my bad english languange)

[@marcelowind]

Just wanted to let you know that I really enjoy your videos. This might get buried under an 'seepage' of other comments.. But just putting it out there

[@fatyredhot]

as a mechanical engineering student your videos are great. i love what you cover， keep up the good work。

[@Jemboj2895]

3 Gorges Dam has been real quiet since this video.

[@nikanj]

The animations are really helpful in illustrating these concepts. I feel like more people should appreciate the work that goes into them. I don't know if Grady produces everything by himself but the production quality is really top class.

[@patrickeh696]

Which is why you bring the footing down to bedrock.

[@PracticalEngineeringChannel]

Not everywhere has bedrock close to the surface.

[@patrickeh696]

Of course not. I learned that in geology class over 40 years ago. But, that just means not everywhere is suitable for a damn. ;) I left the latter unsaid as it is obvious to anyone who knows a bit of geology.

[@dicksonteoh]

And over overconsolidated soil, clayey soil's bearing capacity is dependent of cohesion too.

[@WarrenGarabrandt]

This got me thinking: does everywhere have bedrock? I mean, do we just dig down until we hit a lot of rocks and call that "bedrock", or is it a solid slab of rock that literally spans the entire tectonic plate with no gaps (except volcanos I guess) and no way around it?

[@massimookissed1023]

Warren Garabrandt , different areas have different types of bedrock and at different depths. Sometimes a decent bedrock is just too deep to be economically viable to reach. Manhattan has skyscrapers at either end because of decent hard schist bedrock; not so much in the middle though.

[@rotulaelectrica]

Your video reminds me of a story that the professor of hydraulic structures told us during a class, in the University. "The mayor o a small town decides he wants to have a dam on a creek. He builds it and soon after its completion and fill-up, the supervisor comes rushing to him. Mr. mayor, there is no more water in the lake. How can that be? It's impossible. No sir, there is no more water... ... Soon after, discovering that 10 km downstream a village was flooded" Btw, awesome videos you have. Thanks for sharing the good stuff, the engineering stuff.

[@ZweiSpeedruns]

I'd like to see the full time-lapse of the dam failure if possible, I'm a bit sad there were only a few scattered clips of it

[@VoodooTrashPanda]

Practical Engineering has some great videos discussing liquefaction. Highly recommended

[@thumbnail8087]

If this happens in real life .... You will say "DAMN"

[@privateinformation9384]

Could you build a model showing the affects of fracking? With all the dialogue going on about this subject (both for and against), it would be interesting to see an engineer put it to the test in a controlled environment.

[@ancientmonkey5327]

Did you know the Hover Dam was supposed to be twice as tall as it is now? After some re-evaluation, they thought it would be 2 dam high. I’ll see myself out...

[@AksamRafiz]

Stay out.

[@patrykmazurkiewicz3128]

You ar a very good engineering educator! Great to listen to you! All the best!

[@PyreVulpimorph]

The quantity of puns in these comments IS TOO DAM HIGH! ;P

[@folf]

Pyre Vulpimorph DAM RIGHT!

[@derricka7751]

I sea you tried to fix that by lowering the quality of puns with your comment.

[@paulkurilecz4209]

Great explanation. It also explains why the method to deal with a sand boil on a levee is to stack sandbags around to a height where the flow then stops.

[@PixelBytesPixelArtist]

“Oh no, we’ve fallen into nesquick sand!”

[@skippyjones180]

I LOVE how you actually build the example!

[@probablynaz1731]

"that damn seabithch"

[@GabrielTobing]

2:10 I love how the water just goes up, forgetting all about the 9.8m/s gravity acceleration that is supposed to make it go downwards.

[@mbainrot]

I'll be Dammed if any structure I build ever stands the test of time :) #dadjokeoftheday? Thanks for the very informative videos, it's interesting to see how such inanimate stuff like dirt can reek havoc. Particularly how the piping causes a positive feedback loop

[@VanessaScrillions]

My major was soil science in college. I graduated years ago but I adore your videos. It makes me wish I had pursued a career in soil 😢

[@Abdega]

"Dam Failure" Hey that's my nickname! Haha…ha… *sob*

[@rp003.0]

nice one m8!

[@gideonmiles7161]

Great video! I really enjoyed learning why my sandcastles always fall down whenever Im at the beach... and why dams could collapse if we arent careful...

[@tisFrancesfault]

Nobody likes seepage.. it gets ...messy.

[@TheUserid82]

Unless they are trying to get larger ground water reserves.

[@benritchsmith]

I would like to know of other ways in which water dams control for seepage: aprons on the detainment side; usage certain soils / materials on retainment side; and soil compaction. And how are existing dams fixed after seepage starts. I love your work and am always excited to see what is next! -Ben Ritch-Smith

[@greenmario3011]

> S E E P A G E

[@Nelster]

This video makes all the time I spent drawing flow nets in school worthwhile.

[@alangrant5278]

I love your stuff Grady. It’s always a please to watch and learn. Thanks.

[@ASCENDANTGAMERSAGE]

This video was a bit quiet but a joy to watch as usual!

[@gtrdude4]

Ok now this person has everything I love to watch I’m subbing

[@hyenalingo]

I'm pretty certain you are single handedly keeping the acrylic Industry alive

[@jashencloma7690]

as a CE student this is really helpful to me as it helps me understand diff terms and how they occur

[@LeCharles07]

The humor is so dry I need a glass of water. 10/10 I loved it.

[@gabrielrodriguesdasilva4305]

Wonderful explanation about piping ( "sand move" )!! ( I'm brazilian's student and my teacher indicate your video for us class. )

[@LogicBob]

Another excellent episode Grady!

[@ngm_4092]

fantastic job and a fantastic presentation. You help me wrap my head around the concept

[@wbscherner]

What an incredible videol. I'm civil engineering student and I'm in love with this channel

[@prafullgupta5248]

Awesome work! Nice to see so much enthusiasm.

[@kenmuggli4613]

Thank you Grady, you do excellent work.

[@amayizingnicollama]

Your videos are such great quality! some of the best on youtube

[@RedWingsninetyone]

Very strange that I've been watching a lot of your videos on dams recently just prior to 2 dam failures near my brother's house.

[@zipp4everyone263]

I love these videos. You take a complex matter and make it easy to understand and start the theorising process in your viewers. Thats great! However in this video you didnt really spend a lot of time adressing the problem, something id love to see more of. Like: * used methods for displacing or removing the issue. * Mitigation tactics after the issue has established itsself * Theories surrounding the issue and what the theories can teach us about solutions. Those points would be really nice to cover in my opinion :)

[@BruceAUlrich]

Learned a lot! Thanks for putting this together!

[@라라라-z5p]

what a nice demonstration! thanks for the video!

[@bdot02]

I have always wanted to see demonstrations like you have on your channel. Thanks for building these awesome props!

[@martinstent5339]

Seepage can be good too! We live near the Rhein river and get our drinking water through seepage. Specially constructed “filters” or buried sandbanks allow the river water to seep into collection points from where it is pumped to the water treatment plants where it is turned into drinking water.

[@ven950]

These videos are extremely enjoyable and interesting. I love your content, man.

[@trevordavis7396]

From watching your videos i feel like i have become a engineer!! Thanks for another great video!! 🙏🏽

[@FecheVolta]

Hey Grady great video as always, but a little on the short side. Would've liked to see some more examples. Can't wait for the next one!

[@jcr723]

Grady, here's your dam comment...this is one of your best videos. I live in N. California and have been watching the work done to repair the Oroville dam spillway. Have you thought of discussing that event? Or perhaps talking about the reason a spillway is needed in an earthen dam - to prevent water going over the top of the dam itself. I'm not entirely clear on why water over the top of the same is so dangerous. Perhaps that could be a topic. Thank you and keep up the great work!

[@WorBlux]

An earthen dam can have a good strength, but they don't resist erosion at all being made of unconsolidated materials. Water flow over the top washes material of the dam away faster than the water level drops, leading to a cascading failure. A spillway is supposed to allow an exit path for the water and energy behind it in a way that does not erode the dam.

[@tiffanyg85455]

Wow! You just made me realize i might be interested in geotech! Thank you! Very cool video and demos.