19^th Century Mississippi River Bridges Series

The Mississippi was the last major river to be crossed as the nation moved to the west. From its headwaters in Lake Itasca in Northern Minnesota to its discharge into the Gulf of Mexico, the river, with its tributaries, drained the entire United States between the Appalachians and the Rocky Mountains. It had a watershed of 1,245,000 square miles or approximately 40% of the country’s total land mass. It formed the boundary of ten states; Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Louisiana, and Mississippi. With the advent of the steamboat, it became a major shipping lane, and shippers wanted free navigation of the river without bridge piers.

The New York State Thruway bridge across the Schoharie Creek collapsed on April 5, 1987, during a flood, killing 10 people. Unlike many of the failures discussed previously, this was in the lifetime of many readers.

The first bridge across Tampa Bay connecting Rubonia, FL, with St. Petersburg, FL, opened on September 6, 1954. The main structure was a steel cantilever span with a length of 1,584 feet built by the Virginia Bridge & Iron Company. It replaced a ferry from Point Pinellas on the southerly side of St. Petersburg to Piney Point just north of Rubonia. There were two flanking deck truss spans of 250 feet 3 inches on each side, followed by low-level deck spans. A second parallel span of the same dimensions was built just to the west in 1969 but did not open until 1971 due to foundation problems. This provided two lanes in each direction, and the road became I-275, with the old bridge handling northbound traffic and the newer bridge handling southbound traffic. The total length of the central bridge was approximately 4.4 miles, and the total length of the entire project was 14 miles.

The Silver Bridge across the Ohio River connecting Point Pleasant (West Virginia) and Gallipolis (Kanauga, Ohio) was opened to traffic on May 30, 1928, along with a sister bridge connecting St. Mary’s (West Virginia) and Gallipolis (Ohio), also across the Ohio River. It was called the Silver Bridge due to the color of paint used and was built just north of the intersection of the Kanawha River with the Ohio River. They were both vehicular bridges built as toll bridges by the Gallia County Ohio Bridge Company. The federal government’s approval was required, and bills were submitted to House and Senate for consideration. In December 1926, The Corps of Engineers informed the Bridge Company they must, in accordance with the act, submit a “plan of the bridge showing the length and height of spans; width of draw openings; position of piers, abutments, fenders, etc.”

Galloping Gertie, Part 2

The design evolution for the Tacoma Narrows Bridge (aka Galloping Gertie) was presented in the February 2022 issue of STRUCTURE. Soon after opening, the Tacoma Narrows Bridge exhibited significant vertical movements under various wind conditions. To address the issue, the owners and designers tried various modifications and were investigating additional steps to control or at least minimize the motions.

Galloping Gertie, Part 1

The collapse of the Tacoma Narrows Bridge is one of the most well-known of all bridge failures as its collapse was caught on film. The film was and still is viewed in many introductory physics classes.

Leffert Lefferts Buck (STRUCTURE, December 2010) had long experiences with bridges across the Niagara River. First, he replaced wires and added anchorages to Roebling’s 1855 suspension bridge. He followed this with replacing the wooden trussing with iron and, still later, he replaced the stone towers with iron, all of these without stopping traffic for any extended period. These modifications took place between 1877 and 1886. With his associate R. S. Buck, he replaced Edward W. Serrell’s Lewiston/Queenston Suspension Bridge in 1889. He widened and strengthened Samuel Keefer’s 1868 Honeymoon Suspension Bridge in 1888. Unfortunately, the deck collapsed in a fierce windstorm in 1889, shortly after it opened. He rebuilt it within two months. In 1895, the owners wanted to widen the bridge and have it support trolley traffic. Buck was chosen to design and build an arch bridge under and around his bridge in 1897. He chose a braced arch, open-spandrel span of 840 feet that made it the longest arch span in the world when it opened on June 20, 1898.

After the collapse of the Quebec Bridge in August 1907, an Engineering Committee was formed under the supervision of the Transcontinental Railway Commission to undertake a complete redesign of the bridge. The Board consisted of one Canadian, H. E. Vautelet, one American, Ralph Modjeski, and one British Engineer, Maurice Fitzmaurice. Engineering News wrote of the Board,

A bridge had been proposed across the St. Lawrence river for many years when the Phoenix Bridge Company and Theodore Cooper were selected to build an 1,800-foot-span cantilever bridge. The span would be the longest cantilever in the world, surpassing the Firth of Forth Bridge with its two spans of 1,710 feet. Cooper was initially selected as a consultant to the Quebec Bridge & Railway Co. to recommend a design from the many submitted in a design competition. He selected the Phoenix Bridge design as it was “an exceedingly creditable plan from the point of view of its general proportions, outlines, and its constructive features” and was the “best and cheapest plan and proposal of those submitted to me…”

Dry Creek Bridge Failure

On the Denver & Rio Grande Railroad running from El Paso on the Rio Grande River through Pueblo to Denver, Colorado, the World’s Fair Flyer was traveling southerly towards Pueblo on the early evening of August 8, 1904, during a severe storm. At approximately 8 miles north of Pueblo, the line crossed an arroyo (generally dry creek bed). The arroyo was about 100 feet wide and 14 feet deep with steep banks.