The Bunker Hill Bridge is the visual centrepiece of Boston’s giant Central Artery/Tunnel Project. The entire project consists of the reconstruction of an 8 km portion of Interstate Highway 93 through downtown Boston, the extension of I-90 to Logan Airport through the new underwater Ted Williams Tunnel, and the reconstruction of the extremely complex interchange of highways I-93 and I-90. The project in downtown Boston imposed severe constraints on design
and construction, including difficult geological and ground-water conditions, the presence of a complex network of existing underground utilities, and the need to maintain intensive highway and commuter rail traffic at all times during construction.

The fundamental challenge of the art of bridge design is to develop a structural concept that provides maximum economy and aesthetic significance simultaneously. Safety, serviceability, and durability have been codified in great detail in design standards and must be satisfied as specified for any structural system. In this sense, therefore, these requirements are not relevant to the art of bridge design, which by its nature defies codification.

The autors address the numerous challenges faced in this project.