A replacement bridge under construction at the second-busiest port in the U.S. isn’t just a crucial route for cargo trucks and Southern California commuters – it’s a concrete-and-steel science experiment for engineers and seismologists.

The new bridge, which will stretch 8,800 feet over the Port of Long Beach, is being built with about 75 seismic sensors that will measure the forces imparted on the span when one of several nearby faults set off an earthquake. It will replace the Gerald Desmond Bridge, though it’s unclear if it will retain that name.

The new bridge is due to open next year.

“New bridges don’t come along very often, so it’s exciting,” said Dr. John Parrish, head of the California Geological Survey. His agency’s Strong Motion Instrumentation Program will be among those crunching the information the sensors capture. The data will be added to the state’s database of earthquake knowledge.

California’s bridges and other infrastructure have been outfitted with quake sensors called accelerometers since the 1970s. The eastern span replacement of the San Francisco-Oakland Bay Bridge that opened in 2013 has more than 200.

But the building of the new Long Beach span, south of Los Angeles, marks the first time the sensors have been incorporated into the design of a California bridge from Day One, said Duane L. Kenagy, an engineer and the port’s interim deputy executive director.

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