Such media giants as the New York Times and BBC sought the help of engineering experts, including Sanjay Arwade, Professor of Civil Engineering at UMass Amherst, to help explain the disastrous collapse of the Francis Scott Key Bridge in Baltimore on March 26, when a 95,000-ton container vessel collided with one of the supporting pillars, and the massive southern and central spans of the bridge collapsed within seconds. Arwade told the Times that, if the vessel took out one of the bridge’s support piers, a collapse would be almost inevitable. “For any long-span bridge,” he said, “the complete loss of one of the piers is going to be catastrophic.”

Among other comments, Arwade also explained to the BBC that “This is a really big ship. And the momentum and energy associated with that ship moving even at just a couple of kilometers an hour is tremendous.”

The Times article colorfully set the scene of the disaster. “As a spring tide rushed out of Baltimore harbor just after midnight on Tuesday, the hulking outlines of a cargo ship, nearly three football-fields long and stacked high with thousands of containers, sliced through frigid waters toward the Francis Scott Key Bridge. The vessel, the Dali, was a half-hour into its 27-day journey from Baltimore to Colombo, Sri Lanka. 

“Then the lights on the Dali went dark. The crew urgently reported to local authorities that they had lost power and propulsion. The ship bore down on the bridge. In a scene captured from a livestreaming camera, the ship smashed into a pillar of the bridge with so much force that the massive southern and central spans of the bridge collapsed within seconds.”

The BBC reported that “At a press conference on Wednesday [March 27], U.S. Transport Secretary Pete Buttigieg said the Key Bridge was "simply not made to withstand a direct impact on a critical support pier from a vessel that weighs about 200-million pounds. The Key Bridge was completed in 1977. At the time, the vessels it would have been designed to allow to pass under were much smaller than today's behemoths, including the 95,000-gross-ton Dali.”

As Arwade commented to the BBC, “Design lifetimes are so long - over 100 years sometimes - that the demands on the structure can change in ways that are hard to foresee at the time of design and construction.” Then Arwade explained that designing supporting redundancy into the columns holding up a long span bridge would be “exceedingly difficult to impossible.” 

Arwade’s wide-ranging research interests include: probabilistic mechanics; material mechanics; historic structures; structural reliability; computational solid mechanics; structural aspects of wind-energy development; and structural design of green buildings. 

In addition to his many other accomplishments, Arwade was recently named the director of an important national wind-energy center that will be based at UMass Amherst. The $11.9-million Academic Center for Reliability and Resilience of Offshore Wind (ARROW) is a new national center of excellence designed to accelerate reliable and equitable offshore-wind-energy deployment across the nation and produce a well-educated domestic offshore-wind workforce. See (April 2024)

Article posted in Faculty