Charles C. Sunderland was an engineer at John A. Roebling’s Sons Co. (JARSCO) for 50 years, who developed several advancements in the engineering of steel wires and ropes, as well as prestressed concrete. His days at JARSCOs began in 1901 when he was hired as a draftsman. It was during the following years when he climbed the l
adder until the 1920s when he worked on the Delaware River Bridge.
The Delaware River Bridge, better known as the Benjamin Franklin Bridge that connects Philadelphia to Camden, was considered the longest suspension bridge when it first opened in 1926 till 1929. The two primary cables were produced by Page Steel & Wire Co., woven together with 18,666 No. 6 Wires, reaching a total diameter of 30 inches, however, it was JARSCO who tested the integrity of the No. 6 Wires.
On left: Elastic Curve Test and handwritten notes from John A. Roebling’s Sons Co. On right: Photographs of Wire Testing
By 1929, Charles Cecil Sunderland was appointed as the Chief Bridge Engineer in JARSCO’s new Bridge Division. JARSCO specialized in the fabrication of wire ropes, since the 1840s when first invented the 80-ton wire rope machine. The company famously finished the construction of the Brooklyn Bridge and secured their reputation as a bridge building company. However, it was Charles C. Sunderland, who carried the Roebling Company as a major bridge construction firm in the first half of the 20th century through his innovation.
Sunderland developed new methods of fabricating wire ropes which were responsible for some of the longest spans in the world. During his lifetime, he would make lasting impressions on the civil engineering world with his work in prestressed wire cables and concrete. Blair Birdsall, who worked under Sunderland’s guidance for a brief time, mentions and references to Sunderland’s works, considering Sunderland his mentor. It’s evident in his footnote writings in his files that Sunderland was a brilliant man.
In the margin of an article written by Gustav Lindenthal on long-span bridge design, Sunderland constructively criticizes, “If an inexperienced man like Lindenthal were to make a cable, he would surely produce a slack bight in the bottom of the strands at middle of cables – This is eliminated by clamping the cables every 20 or 30 feet.”
By Zion Um
Gasparini, Dario A. “Charles C. Sunderland and the Diffusion of Prestressing Technologies in the Americas.” Proceedings of the Third International Congress on Construction History, Cottbus, May 2009. pg 655-661. http://engineering.case.edu/eciv/sites/engineering.case.edu.eciv/files/Cottbus2009Sunderland1.pdf. Accessed on 6 June 2014.
Williams, Russell Byron. “New Delaware Suspension Bridge.” Engineering World. 1926, pp 317-318.