Largest Single Span Concrete Bridge Built

In a few weeks the great concrete bridge over Wissahickon creek will be declared open to the public. When this bridge is opened two suburbs, formerly many miles apart, will be brought close together. It is planned at the formal opening of the bridge to have the leading citizens of both suburbs march from opposite directions and meet in the center of the span.

The bridge is the largest in the world of pure concrete without reinforcement, and is unique in many other ways. It has attracted attention among engineers all over the world. The chief engineer of London, Sir Maurice Fitzmaurice, who inspected it recently, declared it was worth a trip across the ocean to view the bridge.

The length of the bridge is 525 feet and its height from the bed of the Wissahickon 147 feet. The sweep of the main arch is 233 feet in length, while the approaching spans measure 53 feet each.

Nearly 300 men were employed more than two years to build the bridge, and 19,000 yards of concrete, weighing more than 40,000 tons, were used. Before the concrete work was begun an entire bridge of wood, called the false work, was erected. This false work was no small affair. It used up 360,000 feet of timber, 130 tons of structural steels, 20 tons of three-quarter inch bolts and two tons of washers for the bolts. The cost of the construction was $259,000.

View more articles about Walnut Lane Bridge