Robert Silman, known for repairing ailing structures, died July 31. The 83-year-old structural engineer succumbed to cancer—first diagnosed in 1984.


“Bob had the ability to do wonders by weaving structural systems into the historic fabric” of aging landmarks, says John H. Beyer, founding partner of Beyer Blinder Belle Architects and Planners. "He had a remarkable sensitivity" to both architecture and restoration, unafraid to do the "minimum amount to make something work," adds Beyer, who collaborated with Silman for 50 years, initially on federal subsidized housing. 

Robert A.M. Stern, founder-senior partner of the eponymous architect, calls Silman “a gentleman, a humanist, a preservationist to the core and a great engineer.”

Silman earned a bachelor of arts from Cornell University, followed by a bachelor’s and master’s of civil engineering from New York University. In 1957, he started working for Tishman Realty & Construction Co. Stints at engineers Severud Associates, Ove Arup &  Partners and Ammann & Whitney followed, before he founded Robert Silman Associates in 1966. He led the firm through 2012, when he became its president emeritus. At the time of his death, Silman was on a summer break from his routine of four-day work weeks, building up the New York City-based firm's Boston office.

“He taught us to find joy in everything we do, serve clients through excellent engineering and nurture young professionals,” says Joseph F. Tortorella, president of the 165-person firm, now named Silman. 

For Frank Lloyd Wright’s Fallingwater, Silman devised a post-tensioned-concrete-slab solution to sagging, caused by insufficient reinforcement of the 15-ft by 62-ft cantilevered portion of the landmarked house (ENR 3/25/2002 p. 17).

After the discovery of cracks and movement of the exterior walls of Wright's iconic Solomon R. Gugenheim Museum in New York City, Silman's team developed a monitoring plan to measure the movement; laser-scanned the building's unusual geometry; and did nondestructive testing and material testing to determine the construction. The firm then created a finite element model of the main rotunda and designed structural repairs, which included carbon-fiber reinforcement on the inside of the walls and dampers at their tops. 

To fix sagging Z-profile beams of the tiered roof of Wright’s Wingspread near Racine, Wis., Silman turned to sailboat composites and aircraft aluminum (ENR 8/18/1997 p. 76).

Inspiring the Next Generation

Silman was devoted to inspiring the next generation, especially by teaching architecture students. Since 2014, he lectured at the Harvard University Graduate School of Design. He also had taught at Columbia University, Yale University, City College of New York and Cornell University. From 1973-85 he taught at the Institute for Architecture and Urban Studies (IAUS) in New York City.

One former student, in Silman's philosophy of technology course at Columbia, reflects on his teacher, who later became a collaborator. "The lesson of most significance for me at Columbia was his insight into the holistic approach where engineering, design, social [considerations] and culture blend to achieve remarkable things," says Jack Phillips, a principal with Bergen Street Studio in Brooklyn, N.Y.

Nick Winton, a former student at IAUS and co-founder and partner of Anmahian Winton Architects in Cambridge, Mass., adds, "Bob was a mentor to me as a young architecture student. He taught us structures but he also inspired us with curiosity and respect for design that solved so many complex problems for so many great buildings, and architects, around the world. He was one of a kind."

Silman was involved with historic preservation and sustainability long before they became commonplace, says Tortorella. In 2004, the International Association of Bridge and Structural Engineers gave him its Anton Tedesko Medal for pioneering work on sustainability in structural engineering. In 2013, the Association for Preservation Technology International granted Silman its highest honor--the Harley J. McKee Award. In 2015, the National Trust for Historic Preservation singled him out for its highest honor for an individual--the Louis de Pont Crowninshield Award.

Silman, who was involved in civic works as a volunteer and as a consultant, is credited with helping save the World Trade Center’s survivors’ staircase for an exhibit at the 9/11 museum in Lower Manhattan. In the face of skepticism, “Bob figured out how to remove the treads and risers” and then he designed a lifting cradle to set them into place, recalls Peg Breen, president of the New York Landmarks Conservancy, which gave him its Lucy G. Moses Preservation Leadership Award, in 2010.

"Bob was not only a brilliant engineer, he was one of the loveliest people you could meet," says Breen. "You didn't just like Bob, you loved him."