The Effect of Water on Soil Strength
Вставка
- Опубліковано 21 січ 2014
- In the fifth video in the Bare Essentials of Soil Mechanics series, Professor John Burland explains how important water pressure in the voids between soil particles is in determining the soil's strength. John describes how major disasters can take place if geotechnical engineers don't take into account water pressure in soils. More engineering teaching resources available on expeditionworshed.org
To reinforce the importance of taking water pressure into account, Professor Burland cites the Abervan disaster in which an unstable manmade soil mound above the village of Abervan engulfed a school, killing 116 children and 28 adults.
In the first of two demonstrations, Professor Burland shows how important water pressure is at the contact point between two soil particles. The conclusion is that water pressure reduces the shearing force between particles, reducing overall soil strength.
In the second demonstration, Professor Burland uses the example of building sandcastles at the beach to show how a small amount of water can increase soil strength. He explains this phenomenon by introducing the concept of surface tension.
Learning outcomes
This video will help learners answer questions such as:
Does soil contain air?
Does soil contain water?
Does water make soil stronger or weaker?
How does pore water pressure affect soil strength?
How do I build the strongest sand castle?
What is surface tension?
About the Bare Essentials of Soil Mechanics Series
This video is part of the Bare Essentials of Soil Mechanics series, funded by the Ove Arup Foundation, in which Professor John Burland draws on his many years of practice in geotechnical engineering and teaching to provide listeners with what he regards to be the key knowledge that geotechnical engineers need to understand about soil mechanics in engineering practice.
Prof Burland is based at Imperial College London and has worked on hundreds of interesting projects, the most famous of which was stabilising the Leaning Tower of Pisa.
This work is licensed under the Creative Commons Attribution-NonCommercial 3.0 Unported License. To view a copy of this license, visit creativecommons.org/licenses/b...
Credits
Written and presented by: Prof John Burland, Imperial College, London.
Concept design: www.thinkup.org/
Graphic design:thomasmatthews.com/
Direction/Production: www.ariesfilms.com/
Image credits: coming soon
1:53 I like how he calls friction "sheering resistance".
*shearing resistance
there is a bit of difference between those two
Friction is general term whereas shearing resistance is used in soil mechanics quite often
One of the best demonstrations for a soil mechanics course! love to use it in my undergraduate geotechnical engineering course.
these are a series of good videos !thx for uploading!
i wish there were more videos......his explanation made my day
The best explaination!
This was a fascinating video. I'm a mechanical engineer so I never learned about strength of soils. This is more for civil engineers.
One of the best demonstrations for a soil mechanics course
Great set of videos. Really helped
Thank you for the great explanations.
Wonderfully put together. Well done sir.
Thank you for your contribution !
Brilliant presentation Prof.
what a mind blowing explanation........!
roshan took the words right out my mind seriously kinda creepy.
Thank You for that explanation.
Brilliant explanation by Prof. Burland
Beautiful demonstration!
Really kudos to his calm and clear voice which makes it easier to undertsand. (uni proffs rush their lesson for gods know why reason and ultimately their sentence structure were in mess) The words and phrases his used were precise.
Water actually reduce the effective stress. And shear strength is proportional to effective stress 🤸🏻♂️, that's why it losses it's shear strength.
outstanding video , very helpfull
thanks a lot
Very well explained!
Thanks a lot. Wish I was taught like this
Great experiments to explain the concepts.
what an ingenious explanation and experiment design.
Extraordinary teacher..
what a great explanation, thank you sir
excellent explanation that I have ever seen !!
It is really amazing!!
Thank you so much!
THank you for this video ! Would you do a video to explain negative and positive pore pressure (plz)?
Thank you very much sir. Difficult concepts explained in best possible manner. Thanks for sharing your invaluable knowledge with all engineers and students of engineering. Much appreciated.
this is amazing. I love this.
Wonderful.clear explaination
Thank you. If you can upload with subtitles It will more helps to understand quickly
Well explanation and good examples and understanding
thanks for this great video :)
At 2:10 I first thought: "Is he a bloody magician?"
My man John Burland doing the explanation :O. Thanks sir
Good video for explaining some soil Civil Engineering concepts.
thankyou sir...that is how vetern professors make complex looking things on books so easy...
Excellent info.
Mind opening explanation.
Very good! Thanks sir!
the best one__amazing
Great and Simply explained vedio.❣️Thank you sir.
Nice explanation with physics experiment for High School
But for an Geotechinal Engineer:
1) Moisture Content
2) Surface tension
3) friction or shear strength
4) Optimum Moisture Content
Other than the fact that this knowledge is useful, I could listen to Mr Burland for days! His voice is an instant stress-reducer! (helpful when exams are in two days) :-)
wow.... 😍
looking forward for your next videos eagerly...
tnx alot professor
good job my friend
Thank You.!
Such a nice person!
U explain very well sir
The best explanation ever
very good information
Great ! Great ! Great !
Thank you so much ..
As a civil engineer, I agree with everything that you have just said.
Brilliant explanation of pwp
wow keren beautiful explanation
Profesor, i lived in high tide area, every year i saw many building start to shift to the left or right side. I lived in west borneo. What best advice to build a foundation in high tide area especially if the land is peat most or gambut area?
Thank you so much.
Sir please make an video of skempton pore water parameters
Thanks sir
wow I came here cause my teacher has no clue what his talking about, I might share this with him. Brilliant!
thank sir, i have one question the failure occurs by friction between two particles or water pressure change (hydro -static pressure )
Beautiful
This is master class concept for most of land slide.sir,can u explain the pore water pressure generation in NC-OC clay.I am requesting you plz enplane the Drained and Undrained shear strength behavior of pure clay(whose liquid limit is greater then 250%) .
great
sir can u explain the of shear strength of an expansive soil
I love it!
Nice explanation I am seeing from India
hello, i'm a student who worked on triaxial consolidated undrained on peat soil.. i would like to know if is it okay if pore pressure more higher then back pressure...if not okay..please explain to me why its happen.
Impressive
So the surface tension - is that why we apply some moisture to soils when compacting? Is this the point of reaching the optimum moisture content?
water pressure acting upward which reduce the contact force between solid and beaker is due to water head between solid and bottom of beaker ?
Is shearing resistance same as frictional force?
Excllent
So does this mean that for granular materials, a little bit of water increases the stability, but too much water offsets this increase?
I didn't understand the last concept!
Why the second one is strongest? Even when 2nd & 3rd are same soil? 3rd just have bit more water content. So what .. 2nd will also increase its water content when tied will come in!?
Wow!!!
i like ur video
As surface tension is caused by water and also shear is also caused by water then how can u justify it?
Wish I went to Imperial
I may be dumb, but for the hole in the cup demonstration, wouldnt a nicer explanation be "the water flowing out pushes the cup up so that the cup glides on the water instead of the grippy wood"
Simplified explanation for Engineers at globe
this video is about effects of water to soil?
Empuxo e índice de saturação do solo
I don’t really understand this. Is what he means in a damp soil the surface tension between the grain increases its sheer strength but if you give it too much water it reduces its sheer strength? So how do you check if the soil is too wet?
check the water content.
its like he is from westeros and good explanation
INTENSE
sumpah,,,,, cuma demonstrasi ini yang bikin saya yakin,,, selama ini saya ragu
*But if two particles are fully submerged in water, the increase in water pressure has no effect in the effective stress between particles*
Water is remarkable.
Sheer explanation.
Doing god's work
like explantion keep explain us in future
you never have the "tide come in on the second one"
I think because he's trying to show the difference between a damp soil, and a damp soil affected by a tide. the surface tension on its own will increase the shear strength of a damp soil, but if that damp soil were to be affected by a tide, the water pressure introduced because of that tide will reduce its shear strength.
i think.
@@killadog84 you think, but still clueless right cause this video is completely stupid, and with a cup has a hole was bad a explantion
gteat....great...great
Cup, it is a cup.
The middle sand did not slide because he didn't pour water.
CIVL2210 lol...
Regenerative agriculture is the way forward.
Just like what the GOD says in the HOLY QURAN in Surrah al hij sign 5 GOD says ( we make the soil vibrating by the water )
can you speak little slower please