John Buck Leonard (1864–1945) was a pioneering bridge engineer and architect, early advocate for

reinforced concrete Reinforced concrete (RC), also called reinforced cement concrete (RCC) and ferroconcrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having hig ...

, working mainly in northern California.

Life

Leonard was born in

Union 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 ...

, and educated at

Michigan State Michigan State University (Michigan State, MSU) is a public land-grant research university in East Lansing, Michigan. It was founded in 1855 as the Agricultural College of the State of Michigan, the first of its kind in the United States. It i ...

and the

University of Michigan , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

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 The Southern Pacific (or Espee from the railroad initials- SP) was an American Class I railroad network that existed from 1865 to 1996 and operated largely in the Western United States. The system was operated by various companies under the ...

. Leonard opened his own consulting civil engineering office in 1904. Even in the aftermath of the

1906 San Francisco earthquake At 05:12 Pacific Standard Time on Wednesday, April 18, 1906, the coast of Northern California was struck by a major earthquake with an estimated moment magnitude of 7.9 and a maximum Mercalli intensity of XI (''Extreme''). High-intensity sha ...

, resistance to fireproof

was strong. Leonard's analyses of concrete's superior performance in the earthquake and fire, especially

Ernest L. Ransome Ernest Leslie Ransome (1844–1917) 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. Ernest was ...

's two buildings at

Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...

, 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 and Day Weeks and Day was an American architectural firm founded in 1916 by architect Charles Peter Weeks (1870–1928) and engineer William Peyton Day (1886–1966). Weeks was born in Copley, Ohio, educated in the atelier of Victor Laloux at the Éco ...

. 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 Bridge The Virginia Street Bridge was a historic concrete double arch bridge in downtown Reno, Nevada, US, carrying U.S. Route 395 Business (Reno, Nevada), Virginia Street across the Truckee River. It was added to the National Register of Historic Places ...

Reno, Nevada Reno ( ) is a city in the northwest section of the U.S. state of Nevada, along the Nevada-California border, about north from Lake Tahoe, known as "The Biggest Little City in the World". Known for its casino and tourism industry, Reno is the ...

, 1905 (demolished in 2016) * Clune's Auditorium (aka Temple Auditorium),

Los Angeles, California Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

, 1906 (demolished), with architect Charles Whittlesey *Engineering for the Sheldon Building, San Francisco, 1906, for architect Benjamin Geer McDougall * Fernbridge, over the Eel River south of

Eureka, California Eureka (Wiyot: ''Jaroujiji'', Hupa: ''do'-wi-lotl-ding'', Karuk: ''uuth'') is the principal city and county seat of Humboldt County in the Redwood Empire region of California. The city is located on U.S. Route 101 on the shores of Humboldt ...

, 1911 (unmodified, extant) *

Gianella Bridge The Gianella Bridge was a swing bridge that brought CA 32 across the Sacramento River at Hamilton City, California, between Glenn County Glenn County is a county located in the U.S. state of California. As of the 2020 census, the populati ...

on State Highway 32, a steel

swing bridge A swing bridge (or swing span 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 center of gravity, about which the swing span (turning span) can then pi ...

(one of Leonard's few steel designs) spanning the

Sacramento River The Sacramento River ( es, Río Sacramento) is the principal river of Northern California in the United States and is the largest river in California. Rising in the Klamath Mountains, the river flows south for before reaching the Sacramento–S ...

between Glenn and Butte Counties, 1911 (demolished 1987) *Van Duzen Bridge, spanning Van Duzen River at State Highway 36, Carlotta vicinity, Humboldt, California, 1922 (demolished) * Chili Bar Bridge, spanning South Fork of American River at State Highway 193, Placerville vicinity, El Dorado, California, 1922 (demolished) *Honcut Bridge, spanning South Honcut Creek at Honcut Road, Loma Rica, Yuba County, CA, 1914 (demolished)

References

{{DEFAULTSORT:Leonard, John B. 1864 births 1945 deaths Concrete pioneers Architects from San Francisco University of Michigan alumni People from Union City, Michigan