From the Dardanelles Strait to China, The Great Bridges That Won Earthquakes

The Sea of Japan and San Francisco Bay, the Bosphorus Strait, and Central and South America—all areas known for their high seismic risk and infamous for catastrophic events such as the 1905 San Francisco earthquake, the 1960 Valdivia earthquake in Chile, and the 1995 Kobe earthquake in Japan.

Yet, in precisely these high-risk zones, engineering science has developed increasingly advanced solutions to build spectacular and safe bridges. It is no coincidence that the world’s longest and second-longest suspension bridges—the 1915 Çanakkale Bridge in Turkey and the Akashi Bridge in Japan—stand in two of the most earthquake-prone regions on the planet.

Materials, design, flexibility, and countless other scientific innovations have made these engineering feats increasingly resilient, capable of withstanding high-magnitude earthquakes and extreme weather calamities such as typhoons with winds reaching up to 286 km/h.

Here is the story of the bridges that have triumphed over the forces of nature.

The Dardanelles Strait is one of the most seismically active areas in the world. According to researchers, the Anatolian Plate, which runs through the Strait and horizontally along Turkey’s northern borders, shifts by two centimeters per year relative to the Arabian Plate, increasing stress that could trigger earthquakes.

Over the past two decades, Turkey has experienced three earthquakes exceeding seven on the Richter scale, confirming that 90% of the country is highly seismically active.

This has not prevented the construction of major Turkey bridges over the Bosphorus—two of which were built by the Webuild Group—nor the recent completion of what is now the longest suspension bridge in the world. The 1915 Çanakkale Bridge spans the Dardanelles Strait with a central span of 2,023 meters.

The first idea for a bridge over this isthmus dates back to 1989, but in 1995, the project was shelved due to seismic concerns. However, advances in modern engineering science led to a revived project in 2010 that ensured structural stability even in extreme seismic events.

One of the most innovative features of the 1915 Çanakkale Bridge was inspired by plans for the Messina Strait Bridge. The Turkish bridge has indeed adopted the “Messina deck” technique, which involves the construction of a deck made with two caissons placed at a considerable distance from each other, thus creating a perforated structure that makes it more stable and aerodynamic, capable in this way of withstanding even the most violent winds.

These engineering achievements have given Turkey a strategic infrastructure, as the bridge connects Eastern Thrace with Anatolia, bypassing Istanbul—a megacity of 15 million people—and reducing traffic congestion on the Bosphorus.

The resilience of the Akashi Bridge, which connects Kobe to Awaji Island across the Akashi Strait, was tested even during its construction.

On January 17, 1995, while the bridge was being built and its two 300-meter-high towers had already been erected, the area was struck by a 7.2-magnitude earthquake. The quake, which claimed 6,000 lives in Japan, caused no damage to the under-construction bridge. Engineers had designed the structure to withstand even stronger earthquakes, up to a magnitude of 8.5 on the Richter scale.

To prove its resistance to powerful winds, two 1:100 scale towers were tested in wind tunnels, demonstrating their ability to withstand forces exceeding 150 km/h.

Completed in 1998, the bridge spans a total of 3,911 meters with a main span of 1,991 meters. It remains the world’s second-longest suspension bridge and a testament to modern engineering achievements.

Building a bridge in the very region where the most powerful earthquake in human history occurred is the challenge Chile has undertaken.

The Chacao Channel Bridge, a suspension bridge expected to span 2,750 meters, is currently under construction in the Chacao Channel between Chiloé Island and mainland Chile. This is the same region where, in 1960, a 9.5-magnitude earthquake—the strongest ever recorded—struck.

Beyond the seismic risk, the channel where the bridge is being built experiences strong currents and winds reaching 200 km/h. Nonetheless, the Chilean government aims to complete the project by 2028. The bridge will significantly impact transportation in the region, reducing crossing times to just three minutes compared to the current 30-45 minutes required by ferry.

Apart from the West Coast—especially California—the Memphis region is considered the most earthquake-prone area in the U.S. Known as the New Madrid Seismic Zone, it spans 193 kilometers from Illinois to Arkansas, crossing the Mississippi River near Interstate 40, a critical transportation artery.

Recognizing this risk, in the early 2000s, the Arkansas State Highway and Transportation Department and the Tennessee Department of Transportation funded an ambitious project to modernize the Hernando de Soto Bridge, which carries Interstate 40 across the Mississippi River.

The Hernando de Soto Bridge, 5.3 kilometers long and built in the late 1960s, is one of only two Mississippi River bridges near Memphis. Completed in 2005, the upgrades reinforced all parts of the bridge—including its 164 decks and 160 supporting piers—transforming it into a highly modern structure capable of withstanding even the most severe catastrophic events.