Coatings Industry News

Main News Page


Italy's Morandi Bridge Towers Demolished

Tuesday, July 23, 2019

Comment | More

Late last month, the towers of Genoa, Italy’s Morandi Bridge were demolished, marking nearly a year since the bridge collapse occurred. Thousands were evacuated prior to demolition.

According to the BBC, the two towers brought down amounted to around 4,500 tons of concrete and steel. Water tanks were also put around the tower bases to help prevent dust becoming an issue in the immediate area.

Bridge Collapse History

Late in the morning on Aug. 14, 2018, lightning struck the Morandi Bridge. At the time, 35-mile-per-hour winds were recorded with a thunderstorm moving through the area. A 200-meter (656-foot) section of the prestressed concrete span collapsed, creating a gulf between two sections of the bridge.

The cable-stayed concrete bridge, also known as the Polcevera Viaduct, completed in 1968, was designed by Italian civil engineer Riccardo Morandi. According to the website Retrofutur, the bridge is characterized, as are other Morandi structures, by thin prestressed concrete girders and relatively few stays. Three A-shaped concrete pylons hold four prestressed stays apiece. The website has chronicled numerous projects over the years to reinforce the structure, including steel sheaths over the concrete pylons.

While experts believe that structural weakness contributed to the collapse, previous warnings about the condition of the bridge were issued years before disaster struck. For example, in 2012, the leader of Genoa's business federation noted that the bridge could collapse within 10 years. In 2011, a report from Autostrade per l'Italia, the operator of the A10 highway that ran over the bridge, warned of intense decay.

Morandi penned his warning partially due to the perplexity of the degradation problem—the amount of corrosion that the bridge exhibited even early on wasn't seen on similar structures in different environmental circumstances. At the end of August, Piano offered to help design a replacement structure signifying rebirth and redemption for the affected area.

In late November, testing of bridge debris began, which will help determine what caused the collapse. Demolition began in December. The new structure will have a 3,600-foot-long main steel deck running across 20 spans, supported by 19 piers placed at 164-foot increments.

The new bridge is slated to be open for traffic in April 2020.

Demolition and Research

Tower legs, along with other parts of the bridge, were equipped with explosives, and roads within an almost 1,000-foot radius of the demolition site were closed. The towers were brought down in around seven seconds.

The demolition also occurred 37 minutes behind schedule due to concerns over an elderly man who reportedly refused to leave his home. While his home was found empty, two non-EU citizens were in another building, unaware of the demolition. Genoa Mayor Marco Bucci noted that the work went according to plan.

According to NBC News, after the Morandi Bridge collapsed, research commenced on developing ways to spot bridges that may be at risk. The technique involves computer modeling and high-resolution satellite images to read for shifts in a structure, signs that it may be starting to fail. Some of these changes may be so minute that they will not be caught by visual inspection.

Pietro Milillo, a scientist working for NASA’s Jet Propulsion Laboratory, created a computer model of the Morandi Bridge, using images taken by satellite from 2003 and 2018. Using this information, an algorithm was able to ferret out troublesome shifts, with information running back to 2015.

One of the limitations of satellite-based inspections, however, is being able to tell the difference between alarming changes in the structure and normal changes, which include expansion and contraction. There is also the question of having these kinds of satellites, equipped with what is known as synthetic aperture radar, which can create 3D, high-resolution images, in orbit. The next satellite equipped with this kind of tool is set to launch in 2022.

   

Tagged categories: Bridges; Demolition; Disasters; Infrastructure; NA; North America; Program/Project Management

Comment Join the Conversation:

Sign in to our community to add your comments.


Advertisements
 
DeFelsko Corporation

 
KTA-Tator, Inc. - Corporate Office

 
SAFE Systems, Inc.

 
Tarps manufacturing, Inc.

 
Strategic Materials Inc.

 
Sauereisen, Inc.

 
 
 

Technology Publishing Co., 1501 Reedsdale Street, Suite 2008, Pittsburgh, PA 15233

TEL 1-412-431-8300  • FAX  1-412-431-5428  •  EMAIL webmaster@paintsquare.com


The Technology Publishing Network

PaintSquare the Journal of Protective Coatings & Linings Paint BidTracker

 
EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About PaintSquare.com   |   Privacy Policy   |   Terms & Conditions   |   Support   |   Site Map   |   Search   |   Contact Us