How the Leaning Tower of Pisa Was Saved: Crash Course Engineering #40

This week we’re going underground to explore geotechnical and seismic engineering. We’ll look at how structures connect to the ground and transmit loads through their foundations, and how those foundations need to provide a high bearing capacity. We’ll see how properties of the soil, like shear strength, affect bearing capacity. We’ll also consider happens when the ground experiences stress from seismic activity and how seismic engineers work to counteract those effects.

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[curiousworld]

I'm amazed that the Hagia Sophia is still standing after 1500 years and being built on a fault line.

[Cyber_chelle]

I came here to learn about the tower of Pisa.
learns about dirt.

[WrathOfMega]

Holy cow, just last night I was watching that 'engineering catastrophies' show with my dad and Shini showed up in their portion on The Leaning Tower of Piza and now this!

[wisperingiron]

I just want to say that I think that all you lovely people at crash course do a wonderful job :) I wish such excellent studies aid had been available online back when I was in high school.
I still find it entertaining as an adult though, and it has helped me improve on some of my academic shortcomings.

[MegaAwesomeNick]

liquefaction is no joke. in 1692, Port Royal in Jamaica was hit by an earthquake and the entire city essentially sank into the sand, turned quicksand, killing thousands. People sank into the ground where they stood and when the earthquake stopped the ground solidified burying them alive.

[titlespree]

"We shape our buildings, thereafter they shape us!" - Winston Churchill

[j-sant-animations]

I couldn’t stop staring at that little dark grey Wall-E figurine in the background.

[greul_vietii]

As a geotechnical engineer myself I am happy to see Crash Course introducing its subscribers to this field. However, 10 minutes is barely enough even for a short introduction to geotechnics. Nevertheless, good video.

[tomislavrastovac]

While on the subject of leaning, those shelves in the back are triggering my ocd hard

[HasinaHr]

you summarized 4 years of my academic life in one video

[laportaho]

The sheer amount of elements that need to be factored into consideration totally overwhelms me. I can only say thank you engineers for figuring out these stuff for us.

[ElvenAngel]

I never get tired of this channel. I hope someday you guys do a series on the History of Art!

[sunstone]

Brains, beauty, AND eloquence! I'm in LOVE!

[AncientAccounts]

They just tilted the earth the opposite way

[mrdanman]

Scale model testing is generally pretty rare. It's super expensive, so it's only for more important buildings. Most of the time it's faster to run dynamic models on the computer, or even using simplified static analysis.

[daffyduck]

Ill be the first to admit im still watching this series because i have a crush on her and that accent is so charming

[colinharvey]

I wish we still had crash course history rip.

[mattheusmegdom]

Great video guys. Keep the good work!!!

[beefcurtainz]

We have to save your leaning shelves!!

[jamesryan]

She got this wrong. I did a report on geotechnical performance on Pisa in college. It was not a bearing capacity failure. Pisa is built on overconsolidated clays. During the construction of the tower which took a 100 years. The surcharge incr.reasingly started to squeeze the water from the clays. This is what caused the differential settlement. This process is still happening today. When the water is squeezed from the clays the soil will gain strength. It was calculated that if the tower was built all at once there would have been a bearing capacity failure. This would result in collapse of the towe