Engineers Have Figured Out How the Leaning Tower of Pisa Withstands Earthquakes

iStock
iStock

Builders had barely finished the second floor of the Tower of Pisa when the structure started to tilt. Despite foundational issues, the project was completed, and eight centuries and at least four major earthquakes later, the precarious landmark remains standing. Now, a team of engineers from the University of Bristol and other institutions claims to have finally solved the mystery behind its endurance.

Pisa is located between the Arno and Serchio rivers, and the city's iconic tower was built on soft ground consisting largely of clay, shells, and fine sand. The unstable foundation meant the tower had been sinking little by little until 2008, when construction workers removed 70 metric tons of soil to stabilize the site. Today it leans at a 4-degree angle—about 13 feet past perfectly vertical.

Now researchers say that the dirt responsible for the tower's lean also played a vital role in its survival. Their study, which will be presented at this year's European Conference on Earthquake Engineering in Greece, shows that the combination of the tall, stiff tower with the soft soil produced an effect known as dynamic soil-structure interaction, or DSSI. During an earthquake, the tower doesn't move and shake with the earth the same way it would with a firmer, more stable foundation. According to the engineers, the Leaning Tower of Pisa is the world's best example of the effects of DSSI.

"Ironically, the very same soil that caused the leaning instability and brought the tower to the verge of collapse can be credited for helping it survive these seismic events," study co-author George Mylonakis said in a statement.

The tower's earthquake-proof foundation was an accident, but engineers are interested in intentionally incorporating the principles of DSSI into their structures—as long as they can keep them upright at the same time.

The World’s Largest Underwater Restaurant Just Opened in Norway—Take a Peek Inside

Ivar Kvaal
Ivar Kvaal

Months before it opened, the world's largest underwater restaurant in Norway was already flooded with reservations. Recently, Business Insider reported that Under has finally started serving its first guests. If you can't book a table at the hottest restaurant below sea level, you can look at the photos taken inside to get an idea of the unique dining experience.

In addition to being the largest underwater restaurant on Earth, Under, from the architecture firm Snøhetta, is also the first of its kind in Europe. It's located in the notoriously treacherous waters off Norway's southern coast.

Underwater restaurant jutting out of the sea.
Ivar Kvaal

After entering the angled building from the shore, guests descend into a 100-person dining room with panoramic views of the ocean and passing marine life. The concrete structure is designed to blend seamlessly into the surrounding environment, eventually acting as an artificial reef that attracts plants and animals. The location boasts such biodiversity that Under is also being used as a research center for marine biologists.

Dining room of underwater restaurant.
Ivar Kvaal

Jellyfish in the ocean.
Ivar Kvaal

Once seated, diners will be treated to a seasonal meal from an international team of chefs led by Nicolai Ellitsgaard. The menu highlights locally sourced produce and sustainably caught wildlife. A full meal lasts roughly three-and-a-half to four hours.

Shellfish dish at Under restaurant.
Stian Broch

Spiny crab.
Stian Broch

Dining room of Under, the underwater restaurant.
Ivar Kvaal

Dining room of Under
Inger Marie Grini/Bo Bedre Norge

Seats at Under are fully booked from now to the end of September. If you're content with getting your name on a waiting list, you can try to reserve a table for earlier in the year through the restaurant's website.

[h/t Business Insider]

Frank Lloyd Wright's Designs Are Now Available as Bags, Phone Cases, and More

Frank Lloyd Wright Foundation, VIDA
Frank Lloyd Wright Foundation, VIDA

From Taliesin West in Scottsdale, Arizona to Fallingwater in Mill Run, Pennsylvania, the architecture of Frank Lloyd Wright is worth traveling for. Now you can wear the visionary's iconic style wherever you go with a new line of Frank Lloyd Wright-inspired apparel and accessories.

The new collaboration between VIDA and the Frank Lloyd Wright Foundation marks the first time that Wright's textile patterns have been made available as commercial products. Each item features original art and designs created by the architect. His bold, modernist creations have been printed on scarves, bags, ties, trays, and phone cases. Much like his buildings, the items use colors palettes reminiscent of what you'd see in nature.

Bags with Frank Lloyd Wright design

Frank Lloyd Wright Foundation, VIDA

Phone case with Frank Lloyd Wright design

Frank Lloyd Wright Foundation, VIDA

Wrap with Frank Lloyd Wright design.

Frank Lloyd Wright Foundation, VIDA

Products in the Frank Lloyd Wright line range in price from $30 to $120. You can shop the collection in its entirety at the VIDA online store. (Until June 15, you can use the code MENTALFLOSS25 at checkout to receive 25 percent off your entire order.)

Wearing the fashionable apparel he inspired isn't the only way to appreciate the designs of Frank Lloyd Wright. In May, The Met launched a digital catalog of the architect's forgotten fabrics and wallpapers on its website.

Tie with Frank Lloyd Wright design

Frank Lloyd Wright Foundation, VIDA

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