Bixby Creek Bridge
Bixby Bridge, also known as Bixby Creek Bridge, on the Big Sur coast of California, is one of the most photographed bridges in California due to its aesthetic design, "graceful architecture and magnificent setting".[3][4] It is a reinforced concrete open-spandrel arch bridge. The bridge is 120 miles (190 km) south of San Francisco and 13 miles (21 km) south of Carmel in Monterey County on State Route 1.
Bixby Bridge | |
|---|---|
 Bixby Bridge from its northern end | |
| Coordinates | 36°22′17″N 121°54′07″W / 36.37139°N 121.90194°W |
| Carries |  SR 1 |
| Crosses | Bixby Creek |
| Locale | Big Sur Monterey County |
| Owner | State of California |
| Maintained by | California Department of Transportation |
| Characteristics | |
| Design | reinforced concrete open-spandrel arch bridge |
| Total length | 714 feet (218 m)[1] |
| Width | 24 feet (7 m) |
| Height | 280 feet (85 m) |
| Longest span | 360 feet (110 m)[1] |
| Clearance below | 260 feet (79 m)[1] |
| History | |
| Construction start | August 24, 1931 |
| Construction end | October 15, 1932 |
| Opened | November 27, 1932 |
| Statistics | |
| Daily traffic | 4,500[2] |
| Location | |
 | |
Before the opening of the bridge in 1932, residents of the Big Sur area were cut off during winter due to blockages on the often impassable Old Coast Road, which led 11 miles (18 km) inland. The bridge was built under budget for $199,861 (equivalent to $3.16 million in 2020 dollars[5]) and, at 360 feet (110 m),[1] was the longest concrete arch span in the California State Highway System. When it was completed, it was the highest single-span arch bridge in the world,[6]: 45
The land north and south of the bridge was privately owned until 1988 and 2001. A logging company obtained approval to harvest redwood on the former Bixby Ranch to the north in 1986, and in 2000 a developer obtained approval to subdivide the former Brazil Ranch to the south. Local residents and conservationists fought their plans, and both pieces of land were eventually acquired by local and federal government agencies. A $20 million seismic retrofit was completed in 1996, although its 24-foot (7.3 m) width does not meet modern standards requiring bridges to be 32 feet (9.8 m) wide.
Location
changeThe bridge is "one of the most photographed features on the West Coast" and in the world. It has been featured on "postcards, TV ads, everywhere," according to Debra Geiler, project manager for the Trust for Public Land. The bridge's location on the scenic Central Coast of California, the parabolic shape of the arch, the tall spandrel columns, and the architectural piers contribute to an "intense aesthetic experience."[7][8][3][9] "It's the gateway to Big Sur and the interior has never been logged. The land is pristine." Zad Leavy, former executive director of the Big Sur Land Trust, described the land as "...the most spectacular meeting of ocean and land in the entire United States."[10][11][12]
Characteristics
changeThe bridge is 714 feet (218 m) in total length and 24 feet (7.3 m) wide, with 260 feet (79 m) of clearance below, and has a main span of 360 feet (110 m), which places 50% of the total roadbed above the arch.[1] The arch ribs are five feet thick at the deck and nine feet thick at the springing line, where they join the towers at their base. The arches are four and one-half feet wide.[13] The bridge was designed to support more than six times its intended load.[14]
The two large, vertical buttresses or supporting pillars on either side of the arch, while aesthetically pleasing, are functionally unnecessary. Engineers of later arch bridges such as the Frederick W. Panhorst Bridge omitted them from the design.[15] The Rocky Creek Bridge and the Malpaso Creek Bridge to the north are also open-spandrel arch bridges built of reinforced concrete.
Construction
changeThe state first began building Route 56, or the Carmel–San Simeon Highway, in 1919. A number of bridges needed to be constructed, the largest among them across Bixby Creek.[16]
Bridge design
change
State engineers considered two alternatives to crossing the creek, an inland route and a smaller bridge, or a coastal location and a larger bridge. The inland route would have needed an 890-foot (270 m) tunnel cut through the Santa Lucia Mountains to a 250-foot (76 m) bridge upstream.[16] The engineers selected the coastal route because it was safer, more scenic, and least affected the environment.
California state highway engineer C. H. Purcell and bridge engineer and designer F. W. Panhorst considered whether to build a steel or concrete span. A steel bridge would cost more to build and maintain, as the sea air would require expensive ongoing maintenance and painting. A steel bridge was also less in keeping with the natural environment. Using concrete reduced material costs and allowed more of the total cost to be paid to workers, which was a positive aspect of the design during the Depression.[3] They chose concrete in part because it would not only reduce both construction and maintenance costs but would also echo the color and composition of the natural rock cliff formations in the area.[14]
The state awarded a contract for $203,334 to the lower bidder, Ward Engineering Company of San Francisco, on August 13, 1931. Construction began on August 24, 1931.[14]
Design and materials
change
Over 300,000 board feet (700 m3) of Douglas fir timber, used to build a 250-foot (76 m) high falsework to support the arch during construction, was transported from the railroad terminal in Monterey over the narrow, one-way road to the bridge site. The falsework, built by crews led by E. C. Panton, the general superintendent, and I. O. Jahlstrom, resident engineer of Ward Engineering Co., was difficult to raise, because it was constantly exposed to high winds. Some of the falsework timbers were 10 by 10 inches (250 mm × 250 mm).[17] It took two months to construct the falsework alone. When high waves threatened the falsework foundation, construction was halted for a short time until winter storms abated.[16]
The crews excavated 4,700 cubic yards (3,600 m3) of earth and rock.[18] Eight hundred and twenty-five trucks brought in 600,000 pounds of reinforcing steel.[18] Sand and gravel were supplied from a plant in Big Sur.
Construction required 45,000 sacks or 6,600 cubic yards (5,000 m3) of cement[18] which was transported from Davenport, near Santa Cruz, and from San Andreas.[16] Crews began placing concrete on November 27. The concrete was transported across the canyon on platforms using slings suspended from a cable 300 feet (91 m) above the creek.[17]
The bridge was completed on October 15, 1932,[17] although the highway was not finished for another five years. At its completion, the bridge cost $199,861 and, at 360 feet (110 m), was the longest concrete arch span on the California State Highway System.[14] The bridge was necessary to complete the two-lane road which opened in 1937 after 18 years of construction.[19] The completion of construction was celebrated with a ribbon-cutting ceremony led by Dr. John L.D. Roberts, who had conceived of the need for the road.[20]
References
change- ↑ 1.0 1.1 1.2 1.3 1.4 Bixby Creek Bridge (1933) at Structurae
- ↑ Bridgehunter – Historic Bridges of the U.S.: Bixby Bridge Archived July 24, 2008, at the Wayback Machine
- ↑ 3.0 3.1 3.2 Rutherford, M. A. "A Critical Analysis of Bixby Creek Bridge" (PDF). Proceedings of Bridge Engineering 2 Conference 2009 April 2009, University of Bath, Bath, UK. Archived (PDF) from the original on March 4, 2016. Retrieved December 10, 2012.
- ↑ Spradling, David (April 21, 2015). "Young Bixby Wagons West". Archived from the original on September 14, 2016. Retrieved September 5, 2016.
- ↑ Inflated values automatically calculated.
- ↑ "Big Sur in 1932: On the Precipice of Change" (PDF). California History. 87 (2). 2010. Archived from the original (PDF) on March 29, 2022.
- ↑ Handbook of International Bridge Engineering. Chen, Wai-Fah, 1936-, Duan, Lian. Boca Raton. October 11, 2013. ISBN 978-1439810309. OCLC 859154927.
{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link) - ↑ "Bixby Bridge on Highway One". www.caviews.com. Retrieved 2017-12-06.
- ↑ "Arch Bridges: Bixby Creek Bridge". www.bridgeofweek.com. Retrieved 2017-12-06.
- ↑ "Big Fun in Big Sur". www.oaklandmagazine.com. Archived from the original on December 7, 2017. Retrieved 2017-12-06.
- ↑ McCabe, Michael (March 25, 2001). "Land Trust Saves Big Sur Ranch / Developer pockets $24 million after one-year ownership". SFGate. San Francisco Chronicle. Archived from the original on November 18, 2016. Retrieved November 17, 2016.
- ↑ Studio, Scott Saunder, Design 7. "Cambria Historical Society - Local History: The Building of Highway One". www.cambriahistoricalsociety.com. Archived from the original on 2017-08-18. Retrieved 2017-12-06.
{{cite web}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link) - ↑ "Concrete Arch Bridges California Canyon". Popular Mechanics. Hearst Magazines. April 1933.
- ↑ 14.0 14.1 14.2 14.3 Vitousek, Sean. "Big Sur Bixby Bridge". Archived from the original on November 19, 2011. Retrieved November 13, 2011.
- ↑ Elliot, Arthur L. (1983), "Esthetic Development of California's Bridges", Journal of Structural Engineering, 109 (9): 2159–2174, doi:10.1061/(ASCE)0733-9445(1983)109:9(2159)
- ↑ 16.0 16.1 16.2 16.3 Newland, Renee. "Bixby Creek Bridge". Monterey County Historical Society. Archived from the original on July 16, 2004. Retrieved November 13, 2011.
- ↑ 17.0 17.1 17.2 "Bixby Creek Bridge, Big Sur Coast on Highway One, Calif". California Views Historical Photo Collection. December 1, 2012. Archived from the original on June 14, 2012. Retrieved December 9, 2012.
- ↑ 18.0 18.1 18.2 Longfellow, Rickie (April 7, 2011). "Back in Time". U.S. Department of Transportation, Federal Highway Administration. Archived from the original on January 29, 2012. Retrieved December 16, 2011.
- ↑ "Hwy One - Big Sur Road - History and Issues". www.pelicannetwork.net. Archived from the original on October 18, 2017. Retrieved December 15, 2017.
Other websites
change