MIRED Tunnel was caught up in politics and delayed by wartime shortages but remains a recordholder.

Robert Moses, chairman of the Triborough Bridge and Tunnel Authority (TBTA) and czar of public construction in the New York City metro area, strongly advocated a bridge, which he claimed would be fastest and cheapest to build. The city council approved his plan in 1939, but many disagreed with it, claiming a bridge would destroy historic Battery Park and obscure the New York skyline. Dissidents included First Lady Eleanor Roosevelt, so it was considered more than a coincidence when Secretary of War Harry Woodring vetoed the bridge for reasons of national security.

Tunnel work started in October 1940. Construction began under two separate contracts that called for 4,000 ft of excavation on twin tunnels from both the Brooklyn and Manhattan sides. Excavations to meet at a ventilation shaft just off Governor's Island. By World War II, construction shafts at both ends were completed and tunneling was under way. Wartime material shortages forced work to stop by the end of 1942. It resumed at the end of 1945.

The first two-thirds of the Brooklyn tunnels were in soft ground that demanded shield tunneling under as much as 38 lb of compressed air. The rest was in mixed face and full-face Manhattan schist. As the shields moved forward, cast-iron rings, 32 in. wide and 31 ft in dia, were placed behind them. The Manhattan tunnels were almost entirely in rock, which was conventionally drilled, blasted and mucked out. When they were enlarged to their full dimension, shields were built and used to erect lining rings. A ventilation building at each end and a shaft off Governor's Island serves the tunnel's two center sections. A total of 53 supply and exhaust fans completely changes the air every 1.5 minutes.

The two-lane tubes opened for traffic in May 1950, but under different management. The original managing agency was the New York City Tunnel Authority, whose chief engineer Ole Singstad distinguished himself as chief construction engineer of the Holland and Queens-Midtown tunnels. Back in the 1930s, he had campaigned for a tunnel, rather than a bridge, to link Brooklyn and the Battery. But in 1946, after the authority was merged into Robert Moses' TBTA, the vengeful chief fired Singstad.

The Future Is Now
Fifty years ago ENR celebrated its 75th Anniversary. The editors published a special issue on Sept. 1, 1949, that took stock of the progress of the past years and offered ideas for the future of the industry. The first section, called "Building a Greater America," outlined the key role construction played in shaping American civilization. It gave a historical overview of significant events from 1876 to 1949, citing accomplishments in sewage disposal, buildings, foundations and bridges. The second section called "Molding the Future" was a symposium of provocative ideas. Specialists wrote about problems such as aerodynamic instability, the problem of the Tacoma Narrows Bridge. The story explained that "Suspension Bridges Are Safe Again" with the addition of stiffening trusses and diagonal stays. The problem of the weight of concrete girders for bridges was addressed in "Longer Concrete Girders? Use a Hollow Box." Other titles included "Prestressed Concrete, a New Frontier; Pile Foundations--Less Guess, More Design; Big Timbers From Small Sticks; and Let's Stop Overdesigning Structures."

Hancock: The Light Heavyweight
(ENR Feb. 17, 1949, p. 65)--The Turner Construction Co. used weight-saving tactics in erecting the John Hancock Mutual Life Insurance building on Boston's heaviest foundation. At 526 ft, the 30-story building would be several stories higher than any building erected in the historic city. And the foundation extended to rock 155 ft below street level. A subcontractor drove 1,569 H-piles up to 120 ft long and 36-ft-long H-soldier piles along the building perimeter. The tops of these piles were 15 ft below the street. The contractor then removed 20x60-ft earth prisms 20 ft deep, exposing bearing piles to be embedded in the 10-ft-thick foundation slab. In contrast, above ground construction used cellular steel decking filled with vermiculite concrete to eliminate much formwork. This also eliminated the need to fireproof the steel. The technique produced a smooth floor that reduced safety hazards and eased the use of rolling equipment.