Morandi Bridges: the famous engineer has built several scattered throughout Italy and abroad from the post-war period up to the 1980s. Some are used, others have been closed.
Riccardo Morandi studied prestressed reinforced concrete for several years and in 1948 studied his first patent on the prestressing system. His ability to exploit this economic material contributed to the spread of
the Morandi bridges in the world .
Morandi Bridges: Italian excellence in the world
The Morandi bridges designed and built are many. In the past they have been synonymous with
Italian engineering excellence . In fact, Riccardo Morandi was an innovator of reinforced concrete, who knew how to exploit its strength, economy and functionality.
Riccardo Morandi was of Roman origins, born in the early twentieth century and died on Christmas Eve 1989.
Morandi began his work in Calabria repairing buildings damaged by the 1908 earthquake, and then specialized in concrete structures at the end of the 1940s. Thus were born bridges and industrial constructions and thermoelectric power plants.
The Polcevera viaduct, the symbol of a tragedy
The
Polcevera viaduct (also called Ponte Morandi or Ponte delle Condotte) was a motorway bridge that crossed the Polcevera stream and the districts of Sampierdarena and Cornigliano in Genoa.
Unfortunately, the Morandi bridges have become known for the absurd tragedy of the Polcevera viaduct. We must remember that the tragedy of 14 August 2018 is not to be attributed to design deficiencies as to the failure of maintenance and checks, paid but not performed.
In fact, the bridge was last renovated in the early 1990s. The restoration did not include the tower where the corroded cables would have touched the collapse 20 years later, despite the inspection by the engineers found problems with the water resistance of the concrete.
Engineers suggested annual maintenance, but, according to the report, the next inspection didn't come until 2012, and the necessary investments were still under discussion the year the bridge collapsed. Experts argue that the collapse could have been predicted had the proper investigations been carried out on the tower and its defective supports.
Where are the Morandi bridges located? Let's see together what are the other Morandi Bridges, in addition to the Morandi bridge in Genoa known for the terrible collapse.
1 - Ponte General Rafael Urdaneta, Maracaibo - Venezuela
The bridge connects Maracaibo with much of the rest of the country. It is named after General Rafael Urdaneta, a Venezuelan hero of independence born in Maracaibo.
Made of reinforced and prestressed concrete, the cable-stayed bridge spans 8,678 kilometers (5,392 miles) from shore to shore. The five main spans are each 235 meters long. They are supported by 92-meter-high towers and provide 46 meters of free space for the water below. The bridge carries only vehicles.
The competition for the design of the bridge began in 1957 and was won by Riccardo Morandi, an Italian civil engineer. Morandi's was the only twelve-part concrete project and was expected to be less expensive to maintain, as well as providing valuable expertise in prestressed concrete technology for Venezuela.
Unfortunately, this bridge too was at the center of a tragic accident. In fact, in 1964, less than two years after its inauguration, an oil tanker hit one of the pylons causing the collapse of a part of the structure and the fall of four vehicles into the water. Seven people died in the accident, but the ship remained unharmed.
2 - Ponte Amerigo Vespucci, Florence
Bridge built between 1955 and 1957, cantilevered to cross the Arno river. It is a modern and linear bridge.
The architects Giorgio Giuseppe Gori, Enzo Gori and Ernesto Nelli took care of its aesthetics and integration into the pre-existing Florentine historical context with the choice of materials and sculptures.
The drawings show that one of the key ideas was to use concrete frames by staggering them on the piles of the structure (like when two combs fit together).
At the moment the Amerigo Vespucci bridge is undergoing maintenance.
3 - Viaduct Bisantis, Catanzaro
Built between 1959 and 1962 on a single reinforced concrete arch, it is a road and pedestrian arch bridge.
For a long time it was the second single arch reinforced concrete bridge in Europe and in the world (after the Swedish Sandöbron). Today it continues to represent a great example of Morandi's genius.
4 - Ponte di Vagli Sotto, Lucca
Another Morandi bridge built in Tuscany, this time in Garfagnana, this small bridge is reserved for the passage of pedestrians. The structure consists of a three-hinged arch supported by two crutch frames.
5 - Paul Sauer Bridge, Cape Town - South Africa
“
Storms River Bridge ”, built by Morandi between 1953 and 1956. It is the smallest copy of the Bisantis bridge in Catanzaro. It is an arch bridge with a span of 100 m.
The bridge is located on the Garden Route section of National Route 2, between Cape Town and Port Elizabeth. At a maximum height of 120 meters (394 feet) above the Storms River, it was the tallest concrete arch in Africa until the Bloukrans Bridge, 216 meters (709 feet), was opened on the same road in 1984.
The main arch structure was built in a unique way: the complete arch was divided into four semi-arches which were built with rampant formworks in an essentially vertical position on opposite sides of the gorge. These were then rotated and lowered into a position in pairs to meet in the center, thus forming the completed arch structure.
6 - Wadi al-Kuf, Beida - Libya
Bridge built in prestressed reinforced concrete between 1967 and 1971, it was until the 1980s the cable-stayed bridge with the highest point of light in Africa (282 m). The oblique tie rods were made with the prestressed reinforced concrete technique.
In 1999 it was renovated after some landslides and changed from the original pink color to white.
In 2017, inspections were carried out which identified potential cracks. The structure was then reopened to traffic, despite a distance of 10 cm between the metal fittings that relax in the heat due to the accumulation of sand or debris.
7 - Ponte Pumarejo, Barranquilla - Colombia
The 1536 m long cable-stayed bridge, made of prestressed reinforced concrete, which crosses the Magdalena river. This Morandi bridge was built in the early seventies.
For a long time it was the longest in the country. In addition to serving as a thoroughfare of the departments of the Atlantic Coast, it has been a fundamental element of its socio-economic development.
The bridge has facilitated immigration and trade, but has also caused controversy because the dimensions have compromised navigation on the river. It will be replaced by a new bridge and then demolished.
8 - Carpineto Viaduct, Vietri di Potenza - PZ
The Carpineto bridge of the late seventies, is made up of two parallel cable-stayed bridges for two directional carriageways (each with two lanes). The structure has steel and prestressed concrete pylons. In fact, the bridge crosses a slope and for this reason it was not possible to build pillars.
In 2013, studies and analyzes were carried out on the state of the structures. Structural degradation and the need to carry out further investigations emerged.
9 - Ponte di San Niccolò, Florence
The bridge, built in the nineteenth century with a metal structure and named after San Ferdinando, was mined and destroyed by the retreating Germans. After the war it was rebuilt on a project by the engineer Morandi with an arched structure in reinforced concrete.
The San Niccolò bridge has recently undergone maintenance.
10 - Akragas Viaduct, Agrigento
Built between 1967 and 1970, this bridge too unfortunately does not have a good state of repair. The bridge was closed in 2015 due to extensive structural damage and in order to be able to carry out the necessary maintenance and safety interventions.
11 - Ponte Costanzo - Ragusa
The Costanzo bridge connects Ragusa to Modica. This bridge is made up of a series of concrete pillars and steel cross spans.
Completed in 1984, it was the highest bridge in Italy (168 m) and still today the highest in Sicily.
12 - Viaduct Ansa del Tevere, Rome
Built in 1967, it is the oldest cable-stayed suspension bridge in the city and the only one with a curved carriageway. It is located in the Magliana district along the A91 motorway.
13 - Kinnaird Bridge, Castlegar - Canada
Officially called the
Columbia Bridge , it is a two-lane road bridge that allows you to cross the Columbia River. The Columbia Bridge was built in 1965.
The clients for the bridge construction were looking for something different from the normal steel trusses widely used in North America, so Riccardo Morandi was asked to design a concrete bridge.
After the collapse of the Genoa bridge, the Candese public has openly discussed the design validity and safety of the Columbia bridge.
