The Verrazano-Narrows Bridge

Abstract

This outstanding suspension bridge underwent a long process of preparation, and it has finally served to solve a most urgent and intense problem of communication between Brooking and Staten Island. This bridge represents an exceptional engineering achievement firstly because of the 1,298 m span between its two towers, and the two side spans of 370 m; secondly due to the vast amounts of materials involved in its construction. The suspended deck will have two directions of traffic, each consisting of six lanes, the two directions separated by a central division. The anchorage and foundations reach down to a depth of 50 m. The towers supporting the main suspension cables are 210 m high above the mean sea level. Their prefabricated external metal shell contain inside a complex system of thousands of metal cells. The deck hangs from four main suspension cables, each 90 cm in diameter. Hanger cables, each 55 cm in diameter, support the deck. The cable spinning over the main towers was a difficult and highly complicated operation. Details of this are given in the accompanying diagrams. Simultaneous with the construction of the bridge, the main access roads to it have been improved and altered, in order to chanalise the heavy traffic more effectively towards it. The whole project, including the construction of the bridge and alterations to the approaches, has amounted to a total cost of the order of 400 million dollars. The safety of the personnel working on this project has been very carefully studied. Ellaborate arrangements are being rigidly enforced for the protection of human lives. It is hoped that this huge project will be completed within the present year.