The Deer Isle Bridge encountered wind stability problems that were similar to a bridge found in which U.S. state?
Deer Isle Bridge The Deer Isle Bridge is a suspension bridge spanning Eggemoggin Reach in the state of Maine. The bridge is the only vehicular connection from the Maine mainland to Little Deer Isle, one of the segments that make up the island. The span was completed in March 1939 with a main span of 329 meters (1,088 ft). The bridge was designed by Holton Duncan Robinson and David Bernard Steinman. It encountered wind stability problems that were similar to those of the Whitestone Bridge and the original Tacoma Narrows Bridge, which collapsed shortly after it opened. The problems led to modifications which included numerous cable stays connecting cables to the tower and tower to the deck. The span today carries two narrow lanes of State Route 15.
Waltmire Bridge The Waltmire Bridge is a historic bridge which carried Locust Road across the Mackinaw River 4.9 mi south of Tremont, Illinois. The bridge was built in 1910 by contractor Edward Cooney at the site of Waltmire's Ford, a shallow point in the river that could only be easily crossed when water levels were low. Both the ford and the bridge were named for local farmer John Waltmire. The bridge has a steel Pratt through truss design, which consists of vertical compression supports and diagonal tension supports. The Pratt truss was a common bridge type in the late nineteenth and early twentieth centuries; the Waltmire Bridge is a relatively long example of the type at 187 ft . The bridge, which is now closed to traffic, is one of two surviving metal truss bridges across the Mackinaw River.