Bridge Collapse Cases/Falls View Bridge
Falls View Bridge, 1938
Construction of the Falls View Bridge started in 1895 and was completed in 1898. The structure was a two-ribbed steel arch of 256 m (840 ft) span. Each rib was a two-hinged truss arch with a uniform depth of 7.9 m (26 ft) and a rise of 45.7 m (150 ft). The chord members were plate and angle box sections. Most of the other members were steel sections with lattice connections. The original wooden deck of 14 m (46 ft) width carried two-track street railway and was supported by unbraced single spandrels. The four concrete and stone foundations rested in solid rock about 12 m (40 ft) above the normal water level.
The arch bridge replaced a suspension bridge which was built in 1868 with wooden towers and floor system. Later the wooden elements of the structure were changed to steel, and on January 10, 1889 the entire deck was carried away by a windstorm. The structure was repaired and opened to traffic, but was judged to be inadequate and it was decided to build an arch bridge.
On January 27, 1938 the Falls View arch bridge, just below the Niagara Falls, was torn from its foundation as a result of the worst ice jam on record. The bridge was a tourist attraction, known as the Honeymoon Bridge.
The ice jam was formed during the night of January 25, 1938 and by the following afternoon it had piled up to a height of 15 m (50 ft) above normal river level, or 3 m (10 ft) above the pins supporting the arch. The ice pack moved downstream like a glacier for about 122 m (400 ft) covering at least 9 m (30 ft) of the upstream truss, causing the failure of many of the bracing members. Shortly thereafter the structure was closed to traffic. The movement of the ice pack was halted, but the upstream truss continued to move very slowly downstream accompanied by further buckling and failure of secondary members. On the afternoon of January 27, the buckled section of the lower chord broke with loud report and the bridge collapsed. The bridge was replaced by the Rainbow Arch, a fixed arch rib of 290 m (950 ft) span.
This is a very unusual case where the principal cause of the failure was the proximity of the ice mass to the structure and the flexibility of the structure. Although it is not always possible to design for unusual natural phenomena, the foundation of bridges should be protected where possible.
Other Falls View Bridge Websites
- "Record Ice Jam at Niagara Falls Wrecks Famous Arch Bridge", (1938), Engineering News Record, Vol. 120, February 3, pp. 161,168-169.
- "Cable and Deck Salvaged from Falls View Bridge", (1938), Engineering News Record, Vol. 120, February 24, pp. 311.
- "Falls View Bridge Sinks in River", (1938), Engineering News Record, Vol. 120, pp. 559.
- “Ice Power,” Engineering News Record, (1938), Vol. 120, pp. 171.
- Buck, R.S., (1938), "Niagara Arch Memories," Engineering News Record, 120, February 24, pp. 297-298.
- "Niagara Falls - Honeymoon Bridge Collapse." Niagara Falls Thunder Alley. Niagara Falls. Web. <http://www.niagarafrontier.com/madisonsale.html>.
- "Upper Steel Arch Bridge (Niagara Falls)." Wikipedia, the Free Encyclopedia. Wikimedia Foundation Inc., 7 Aug. 2011. Web. <http://en.wikipedia.org/wiki/Upper_Steel_Arch_Bridge_(Niagara_Falls)>.
- "Niagara Falls Bridge History | The Honeymoon Steel Arch Bridge in Niagara Falls." Niagara Falls Info - Official Information Guide on Niagara Falls, Canada & Niagara Falls, USA. Web. <http://www.niagarafallsinfo.com/history-item.php?entry_id=1395>.
- "Honeymoon Bridge." Structurae. Nicolas Janberg. Web. <http://en.structurae.de/structures/data/index.cfm?ID=s0002254>.