Canal Lake Concrete Arch Bridge is an

arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct ...

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

, Canada, spanning a portion of

Canal Lake Canal Lake is a lake of Ontario, Canada, situated in the City of Kawartha Lakes. The lake is triangular, roughly long and at its widest point, with an area of . The depth ranges from to a max depth of . Canal Lake is a medium size lake with a ...

on the

Trent–Severn Waterway The Trent–Severn Waterway is a canal route connecting Lake Ontario at Trenton to Georgian Bay, Lake Huron, at Port Severn. Its major natural waterways include the Trent River, Otonabee River, Kawartha Lakes, Lake Simcoe, Lake Couchiching an ...

between Balsam Lake and

Lake Simcoe Lake Simcoe is a lake in southern Ontario, Canada, the fourth-largest lake wholly in the province, after Lake Nipigon, Lac Seul, and Lake Nipissing. At the time of the first European contact in the 17th century the lake was called ''Ouentironk'' ...

. It is north-northeast from the town of

Bolsover Bolsover is a market town and the administrative centre of the Bolsover (borough), Bolsover District, Derbyshire, England. It is from London, from Sheffield, from Nottingham and from Derby, Derbyshire, Derby. It is the main town in the Bols ...

. The closed

spandrel A spandrel is a roughly triangular space, usually found in pairs, between the top of an arch and a rectangular frame; between the tops of two adjacent arches or one of the four spaces between a circle within a square. They are frequently fill ...

bridge is the earliest-known bridge in Canada to be constructed using

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 ...

, and is based on a modified Melan System of bridge reinforcement. In 1988, it was designated a

National Historic Site of Canada National Historic Sites of Canada (french: Lieux historiques nationaux du Canada) are places that have been designated by the federal Minister of the Environment An environment minister (sometimes minister of the environment or secretary of t ...

for representing a transitional period in bridge construction and a milestone in civil engineering in Canada.

Structure

Department of Railways and Canals The Department of Railways and Canals is a former department of the Government of Canada. It had responsibility for the construction, operation, and maintenance of federal government-owned railways, as well as the operational responsibility for ca ...

, the bridge was built in 1905. The original design was for a concrete arch bridge typical of its era. Before construction began, the design was updated by integrating reinforced concrete using a modified Melan System of bridge reinforcement, which had been pioneered by its namesake

Josef Melan Josef Melan (1854–1941) was an Austrian engineer. He is regarded as one of the most important pioneers of reinforced concrete bridge-building at the end of the 19th century. Josef Melan is credited as the inventor of the ''Melan System'', a me ...

in the 1890s. Among the changes were the installation of struts underneath the arch, and a reduction in the mass of the arch and its

abutment An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls ...

s. The concrete mass is reinforced with curved steel

girder A girder () is a support beam used in construction. It is the main horizontal support of a structure which supports smaller beams. Girders often have an I-beam cross section composed of two load-bearing ''flanges'' separated by a stabilizing ' ...

s. The arch is a closed spandrel, in which the

structural load A structural load or structural action is a force, deformation, or acceleration applied to structural elements. A load causes stress, deformation, and displacement in a structure. Structural analysis, a discipline in engineering, analyzes the ef ...

of the deck is carried to the arch ribs via spandrel walls. It has a radius of , and its vertical clearance of is sufficient for vessels to navigate underneath. The deck is wide, and spans over the lake, anchored by reinforced concrete abutments. The concrete spandrel walls are marked to imitate the

voussoir A voussoir () is a wedge-shaped element, typically a stone, which is used in building an arch or vault. Although each unit in an arch or vault is a voussoir, two units are of distinct functional importance: the keystone and the springer. The ...

layout common to stone arch bridges and the "coursed stonework of stone masonry bridge abutments". The bridge was refurbished between April 2018 and February 2019 by GMP Contracting Ltd., the work included patching concrete, refacing the surface and replacing the road deck.

National Historic Site of Canada

The bridge was designated a National Historic Site of Canada on 24 June 1988 for its early use of concrete in bridge construction, for being the earliest-known bridge in Canada to be constructed using reinforced concrete, and for its "close association with the Trent-Severn Waterway". It is one of only a few mass concrete bridges built in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, as the bridge "represents a transitional structure" between earlier stone arch bridges and the advent of reinforced bridges. On 30 August 2008, a plaque was unveiled by

Bruce Stanton Ronald Bruce Stanton (born December 20, 1957) is a Canadian politician who served as Member of Parliament for the riding of Simcoe North from 2006 to 2021. Stanton first ran as a member of the Conservative Party in the 2006 federal election an ...

Member of Parliament A member of parliament (MP) is the representative in parliament of the people who live in their electoral district. In many countries with bicameral parliaments, this term refers only to members of the lower house since upper house members of ...

for

Simcoe North Simcoe North (french: Simcoe-Nord) is a federal electoral district in central Ontario, Canada. It was established as a federal riding in 1867. Demographics :''According to the Canada 2011 Census''; 2013 representation'' Ethnic groups: 87.8% ...

, representing the Historic Sites and Monuments Board of Canada. The plaque, installed on the southwest side of the bridge, states that the Canal Lake Concrete Arch Bridge represents "an important milestone in the history of civil engineering in Canada", as it led to the development of large-span reinforced concrete bridges.

Notes

References

* * * * * * {{refend 1905 establishments in Ontario Deck arch bridges in Canada Bridges completed in 1905 Road bridges in Ontario National Historic Sites in Ontario Trent–Severn Waterway