Dickabram Bridge is a heritage-listed road-and-rail
bridge
A bridge is a structure built to Span (engineering), span a physical obstacle (such as a body of water, valley, road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, whi ...
over the
Mary River between
Miva and
Theebine, both in the
Gympie Region
The Gympie Region is a Local government in Australia, local government area in the Wide Bay–Burnett region of Queensland, Australia, about north of Brisbane, the state capital. It is between the Sunshine Coast, Queensland, Sunshine Coast and ...
,
Queensland
Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...
, Australia. It was the major bridge on the
Kingaroy railway line. It was designed by
Henry Charles Stanley and built from 1885 to 1886 by Messrs
Michael McDermott, Owens & Co. It is also known as Mary River Bridge (Miva). The bridge was registered on the former
Register of the National Estate
The Register of the National Estate was a heritage register that listed natural and cultural heritage places in Australia that was closed in 2007. Phasing out began in 2003, when the Australian National Heritage List and the Commonwealth Heri ...
in 1988.
The bridge is one of three remaining road-and-rail bridges in Australia
and the only one in
South East Queensland
South East Queensland (SEQ) is a Bioregion, bio-geographical, Megalopolis, metropolitan and Statistics, statistical Regions of Queensland, region of the States and territories of Australia, state of Queensland in Australia, with a population of ...
following the completion of the
Burdekin Bridge in 1957. It is the oldest remaining large steel truss bridge constructed in Queensland.
History
The Dickabram Bridge over the
Mary River was the major bridge on the
Kingaroy branch railway line. The contract for construction of the line to
Kilkivan was awarded to McDermott, Owens & Company on 8 August 1884, the contract to be completed by the 1st June 1886. This contract Included several other bridges, drainage structures, formation & track consisting of a total length of railway of and 2
links.
Work was delayed in 1885 awaiting casting of the cylindrical
piers for the central
spans. During construction it was known as the Kilkivan railway bridge, and at least one worker died, as well as two children of workers drowning. The bridge was tested in November 1886 with a two-engine train. The line opened for traffic between Dickabram and Kilkivan on 6 December 1886.
[
The original road bridge across the Mary River at Miva had opened on 30 October 1878. This bridge was damaged by floods in July 1879 and swept away by floods in February 1880. A replacement road bridge was swept away by floods in October 1882.][ Prior to these bridges a punt had operated at the crossing.
It was provided in December 1882 that the proposed rail bridge be built to carry road traffic as well. Because of the delay in opening access roads it was March 1889 before it opened to road traffic.][
The ]steel
Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...
and timber
Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, window frames). ...
truss bridge
A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements, typically straight, may be stressed from tension, compression, or ...
, built by McDermott, Owens & Co., was completed in November 1886 and the line opened for traffic between Dickabram and Kilkivan on 6 December 1886.
The name of the bridge comes from a local Aboriginal word ''dickabram'' meaning sweet potato
The sweet potato or sweetpotato (''Ipomoea batatas'') is a dicotyledonous plant in the morning glory family, Convolvulaceae. Its sizeable, starchy, sweet-tasting tuberous roots are used as a root vegetable, which is a staple food in parts of ...
that grew along the river flats there. The bridge decking was submerged under water only once during the 1893 floods.
The bridge has remained in use without substantial modification. Work since its completion includes undertrussing a span in 1911, strengthening the spans for C17 locomotives in 1935, a concrete base for pier 9 in 1968, and scour protection in 1976. Work strengthening the line from PB15 to C17 standard was completed between 1933 and 1935. Diesel electric locomotives were first permitted in 1977. The decking has been modified by adding a kerb in the 1970s–80s to separate road and rail traffic to save the need for a gatekeeper to control road traffic.
The extensive restoration of the bridge, involving replacement of hardwood timber beams and decking, was completed in April 2009.
Rehabilitation works were carried out in 2017-2019 by the Department of Transport and Main Roads. This involved replacing some of the aged timber girders, decking, piles and other structural elements and re-painting the steel elements with a coating applied to protect the structure from further corrosion. In 2018 the smaller and less complex pier 8 was rehabilitated. The project team identified issues and mitigation measures required before dismantling and in January 2019 starting work on the larger pier 11.
A plaque was erected on 12 October 1986, as an Australian Bicentenary Project to commemorate the historical significance and the centenary of the Dickabram Bridge.
The Kingaroy to Theebine railway was used for agriculture and commercial freight as well as transporting passengers and was one of the first branch lines built in Queensland. The Theebine to Kingaroy line was officially closed in early 2010.
Description
The Dickabram Bridge over the Mary River is long and stands above the Mary River. All spans are metal truss
A truss is an assembly of ''members'' such as Beam (structure), beams, connected by ''nodes'', that creates a rigid structure.
In engineering, a truss is a structure that "consists of two-force members only, where the members are organized so ...
es except for the approach spans which are tied timber girder
A girder () is a Beam (structure), 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 sta ...
s. The two river piers are cast iron
Cast iron is a class of iron–carbon alloys with a carbon content of more than 2% and silicon content around 1–3%. Its usefulness derives from its relatively low melting temperature. The alloying elements determine the form in which its car ...
cylinders; the remaining piers and road deck are timber. It comprises two parallel chord lattice girder
A lattice girder is a truss girder where the load is carried by a web of latticed metal.
Overview
The lattice girder was used prior to the development of larger rolled steel plates. It has been supplanted in modern construction with welded ...
spans either side of a hogback lattice girder span, having steel cross girders, supported on two cylinder piers and two double timber piers.[
]
Heritage listing
Dickabram Bridge was listed on the Queensland Heritage Register
The Queensland Heritage Register is a heritage register, a statutory list of places in Queensland, Australia that are protected by Queensland legislation, the Queensland Heritage Act 1992. It is maintained by the Queensland Heritage Council. As ...
on 21 October 1992 having satisfied the following criteria.[
The place is important in demonstrating the evolution or pattern of Queensland's history.
The bridge is a late 19th-century and essentially unmodified high level road-rail bridge with half-through double by 2 lattice girder approach spans and hogback through double x 2 lattice girder main spans. It was constructed on the site of several low-level bridges that had been destroyed by floods.][
The place demonstrates rare, uncommon or endangered aspects of Queensland's cultural heritage.
It is one of the few extant road-rail bridges in Queensland.][
The place is important in demonstrating a high degree of creative or technical achievement at a particular period.
It is the oldest extant of its type in Queensland with the longest hogback span of its type in Queensland.][
The place has a special association with the life or work of a particular person, group or organisation of importance in Queensland's history.
Its design was associated with the Chief Engineer, Henry C. Stanley.][
]
References
Attribution
External links
*
{{Australian railway bridges, state=autocollapse
Bridges in Queensland
Bridges completed in 1886
Road-rail bridges
Queensland places listed on the defunct Register of the National Estate
Queensland Heritage Register
Mary River (Queensland)
Railway bridges in Queensland
Truss bridges in Australia
Articles incorporating text from the Queensland Heritage Register
Gympie Region