John B. Leonard
Encyclopedia
John Buck Leonard was a pioneering bridge engineer and architect, early advocate for reinforced concrete
, working mainly in northern California.
and educated at Michigan State and the University of Michigan
before going west in 1888. After brief periods in San Diego and Los Angeles, he settled in San Francisco. From 1889 he was employed there doing iron and steel engineering for various firms, including the Southern Pacific Railroad
. Leonard opened his own consulting civil engineering office in 1904.
Even in the aftermath of the 1906 San Francisco earthquake
, resistance to fireproof reinforced concrete
was strong. Leonard's analyses of concrete's superior performance in the earthquake and fire, especially Ernest L. Ransome
's two buildings at Stanford University
, and a constant stream of his articles and editorials in Architect and Engineer of California, changed the city's ordinances and gained national attention.
As of 1913 Leonard was in partnership with William Peyton Day. Together they produced the pamphlet The Concrete Bridge, showing examples and analyses of Leonard's work. In 1916 Day left to form the noted San Francisco firm of Weeks & Day.
Leonard would engineer about 20 buildings in post-1906 San Francisco, become increasing involved in building inspection, and ultimately design about 45 bridges in California.
Reinforced concrete
Reinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
, working mainly in northern California.
Life
Leonard was born in Union City, MichiganUnion City, Michigan
Union City is a village in Branch and Calhoun counties in the U.S. state of Michigan. Located mostly within Union Township in Branch County, it sits at the junction of the Coldwater and St. Joseph rivers; the Calhoun County portion lies within that county's Burlington Township. It is part of the...
and educated at Michigan State and the University of Michigan
University of Michigan
The University of Michigan is a public research university located in Ann Arbor, Michigan in the United States. It is the state's oldest university and the flagship campus of the University of Michigan...
before going west in 1888. After brief periods in San Diego and Los Angeles, he settled in San Francisco. From 1889 he was employed there doing iron and steel engineering for various firms, including the Southern Pacific Railroad
Southern Pacific Railroad
The Southern Pacific Transportation Company , earlier Southern Pacific Railroad and Southern Pacific Company, and usually simply called the Southern Pacific or Espee, was an American railroad....
. Leonard opened his own consulting civil engineering office in 1904.
Even in the aftermath of the 1906 San Francisco earthquake
1906 San Francisco earthquake
The San Francisco earthquake of 1906 was a major earthquake that struck San Francisco, California, and the coast of Northern California at 5:12 a.m. on Wednesday, April 18, 1906. The most widely accepted estimate for the magnitude of the earthquake is a moment magnitude of 7.9; however, other...
, resistance to fireproof reinforced concrete
Reinforced concrete
Reinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
was strong. Leonard's analyses of concrete's superior performance in the earthquake and fire, especially Ernest L. Ransome
Ernest L. Ransome
Ernest Leslie Ransome was an English-born engineer, architect, and early innovator in reinforced concrete building techniques. Ransome devised the most sophisticated concrete structures in the United States at the time....
's two buildings at Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
, and a constant stream of his articles and editorials in Architect and Engineer of California, changed the city's ordinances and gained national attention.
As of 1913 Leonard was in partnership with William Peyton Day. Together they produced the pamphlet The Concrete Bridge, showing examples and analyses of Leonard's work. In 1916 Day left to form the noted San Francisco firm of Weeks & Day.
Leonard would engineer about 20 buildings in post-1906 San Francisco, become increasing involved in building inspection, and ultimately design about 45 bridges in California.
Work
Leonard's work includes:- Virginia Street BridgeVirginia Street BridgeThe Virginia Street Bridge is a historic concrete double arch bridge in downtown Reno, Nevada, USA, carrying Virginia Street across the Truckee River. It was added to the National Register of Historic Places in 1980...
, Reno, NevadaReno, NevadaReno is the county seat of Washoe County, Nevada, United States. The city has a population of about 220,500 and is the most populous Nevada city outside of the Las Vegas metropolitan area...
, 1905 (unmodified) - Clune's Auditorium (aka Temple Auditorium), Los Angeles, CaliforniaLos Angeles, CaliforniaLos Angeles , with a population at the 2010 United States Census of 3,792,621, is the most populous city in California, USA and the second most populous in the United States, after New York City. It has an area of , and is located in Southern California...
, 1906, with architect Charles Whittlesey (razed) - engineering for the Sheldon Building, San Francisco, 1906, for architect Benjamin Geer McDougall
- FernbridgeFernbridge, CaliforniaFernbridge is an unincorporated community at an elevation of in Humboldt County, California, named for an historic bridge, west-northwest of Fortuna.-Town of Fernbridge:...
, over the Eel RiverEel River (California)The Eel River is a major river system of the northern Pacific coast of the U.S. state of California. Approximately 200 miles long, it drains a rugged area in the California Coast Ranges between the Sacramento Valley and the ocean. For most of its course, the river flows northwest, parallel to the...
south of Eureka, CaliforniaEureka, CaliforniaEureka is the principal city and the county seat of Humboldt County, California, United States. Its population was 27,191 at the 2010 census, up from 26,128 at the 2000 census....
, 1911 - Gianella Bridge on State Highway 32, a steel swing bridgeSwing bridgeA swing bridge is a movable bridge that has as its primary structural support a vertical locating pin and support ring, usually at or near to its centre of gravity, about which the turning span can then pivot horizontally as shown in the animated illustration to the right...
(one of Leonard's few steel designs) spanning the Sacramento RiverSacramento RiverThe Sacramento River is an important watercourse of Northern and Central California in the United States. The largest river in California, it rises on the eastern slopes of the Klamath Mountains, and after a journey south of over , empties into Suisun Bay, an arm of the San Francisco Bay, and...
between Glenn and Butte Counties, 1911, razed 1987 - Van Duzen Bridge, spanning Van Duzen River at State Highway 36, Carlotta vicinity, Humboldt, California, 1922
- Chili BarChili Bar, CaliforniaChili Bar is a former settlement and mining camp in El Dorado County, California. It was located on the South Fork of the American River east-southeast of Coloma....
Bridge, spanning South Fork of American River at State Highway 193, Placerville vicinity, El Dorado, California, 1922
Sources
- structurae list of commissions
- extensive biography in Historic American Buildings SurveyHistoric American Buildings SurveyThe Historic American Buildings Survey , Historic American Engineering Record , and Historic American Landscapes Survey are programs of the National Park Service established for the purpose of documenting historic places. Records consists of measured drawings, archival photographs, and written...
data pages for Gianella Bridge, Glenn, CA - full text of "The Concrete Bridge" by Leonard and Day, 1913