Breakthrough in Japanese Railways 8

Railways and Bridges
Junichi Konishi

Railway Construction under British
Engineers: Early Bridges

and Yokohama; it was a rushed project so the required

Although the coffers of the Meiji government at the end of theBridge, had a queen post truss with seven spans measuringlate 19th-century were not overflowing, it decided on a policy

55 ft between piers crossing a river on the Kawasaki

of building railways itself by borrowing money from Britain.

side, and a girder bridge crossing the dry riverbed on the

Railway construction started between Tokyo and Yokohama

Shimbashi side. The abutments were marvellous brickand between Kobe, Osaka, and Kyoto under the oversight

structures, but the central piers were a series of woodenof British engineers because no Japanese engineers hadcolumns. The bridge floor was planked for dual track withlearned railway technology at that time.

rails laid for only one track at the opening. The track wasiron bridges were not ready and all the first bridges were
temporary wooden structures. The largest, Rokugogawa

The first Chief Engineer was 29-year-old Edmund Morelsecured on longitudinal sleepers. Rebuilding of Rokugogawa

who arrived in Japan in April 1870. In addition to technical

Bridge and other major bridges as iron bridges began 3

instruction and overseeing of railway construction, he gave

years after the line opened.

important advice on technical administration and education,

The Kobe to Osaka line (opened 1874) started slightly

leading to the establishment of the Ministry of Works (1870)

later than the Tokyo to Yokohama line with Japan’s first ironand Imperial College of Engineering. Morel died of illness inrailway bridges crossing the Jusogawa, Kanzakigawa, andNovember 1871 before the opening of the railway in Japan.

Mukogawa (gawa is Japanese for river). Other rivers were

While he only served for 18 months, he played a key role

again spanned by temporary wooden bridges. The ironas an advisor on railway construction and in Japan’s later

bridges had iron tube masts joined to screw piles as piersmodernization as a whole.

with pin-jointed wrought-iron truss girders (called latticegirders at the time) on top. The span between pier centres

Japan’s first railway opened in 1872 between Shimbashi

Portrait of Edmund Morel(The Railway Museum)Japan Railway & Transport Review No. 57 • Mar 2011

First Rokugogawa wooden bridge (1872) on Shimbashi–Yokohama Line(Institut des Hautes Etudes Japonaises, College de France)

50Breakthrough in Japanese Railways 8

was 70 ft (21.3 m), so they were short for truss girders.

to American-style pin-jointed trusses, which concentrate the

All three bridges used the same girders, possibly making

load on panel points in accordance with elementary truss

them the first standardized girder design. Three tunnels

theory. Thus, high-level theory would probably be required

were constructed under riverbeds on that section. Brick arch

for a strict analysis of this structure. The design live load

bridges were constructed where embankments crossed

used assumed continued use of small locomotives andsmall rivers, channels, paths, etc.

ignored any future increases in locomotive size.

Later construction between Osaka and Kyoto (opened

Short-span plate girders were either imported from

1896) used iron designs for all main large and small bridges.

Britain or manufactured at the government railways’ Kobe

The largest girders were all wrought-iron, pin-jointed truss

Works using imported materials. Railway workshops forgirders with a clear span of 94 feet and were 99 feet 10 inches

repairing rolling stock had equipment for cutting, bending,long overall to bridge the 100 feet between pier centres. They

punching, riveting, and forge welding of iron so plate girders

were erected across the Kamijusogawa, Kamikanzakigawa,

could be manufactured.

Ibarakigawa, Otagawa, and Katsuragawa.

Upgrading from wooden to iron bridges on the

The earlier wooden Rokugogawa Bridge in the section

Shimbashi to Yokohama and Osaka to Kobe sections was

between Shimbashi and Yokohama was rebuilt with double-

carried out from the larger spans first and the plate girders

track truss girders of the same structure and span as used

used for the upgrades were manufactured at the Shimbashi

for the aforementioned bridges between Osaka and Kyoto.

and Kobe Works.

The truss girders were designed under the supervision

Acquiring Technologies

of technical advisor Dr William Pole in Britain based onJapanese schematic designs and were manufactured in
Britain. On-site construction was completed under the

Although Japan’s railways were supervised at first by British

oversight of the British engineer Theodore Shan.

engineers, the first Chief Engineer Edmund Morel stressed

The 70 and 100-ft girders featured thick frames with

the importance of training Japanese engineers so future

upper and lower chord members and end posts, andrailways in Japan could be built by Japanese. Masaru Inoue,

relatively thin diagonal braces assembled in the Warren

Director of the Imperial Government Railways, took his advice

style by pin jointing. This is a proportion commonly seenand set up a technical training school in Osaka in 1877 toin British small- and mid-sized trusses of the time, but pin

train employees so the railways could become independent

jointing was probably used taking into consideration thatas quickly as possible. As a result, Japanese engineers were

they were for Japan with a low technical development.

able to construct the Osakayama Tunnel between Kyoto

The cross beams supporting the track were laid at equallyand Otsu without the help of British engineers. The wrought

spaced intervals on the chord members rather than theiron plate girder design of the Kamogawa Bridge (opened

panel point section. Also, the stringers were not directlyin 1879) on the same section was by Amane Mimura,

under the rails at first; thick longitudinal sleepers were laida graduate of the technical training school, under theon the crossbeams. Arranging crossbeams closely with thick

instruction of principal engineer T. R. Shervington who lived

longitudinal sleepers distributed the load on the lower chordin Kobe. It was the first plate girder railway bridge designed

members, rather like a wooden construction. This is contraryby a Japanese. Japanese engineers developed abilities
while working under the instruction of British engineers.
Later bridge design was done under the instruction of C.
A. W. Pownall, who was principal engineer from 1882 to1896. Technical training school graduate Seiichi Furukawa
worked continuously under Pownall on bridge design, andhe participated in major projects, such as the arch bridges
at the Usui Pass section of the Shin’etsu Line. He later
designed the Amarube Viaduct (steel trestle, 1912) on the
San’in main line.
By the time Pownall returned to Great Britain, the numberof Japanese who had studied in the USA and Britain had
increased greatly, and bridge design was done by Japanese.
However, design of large truss girders was commissioned toAmerican engineers around 1897, and all design was notdone by Japanese until 1911.

First iron railway bridge in Japan, Shimokanzaki-gawa Bridge (1874)
on Osaka–Kobe Line(S. Onoda)

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Japan Railway & Transport Review No. 57 • Mar 2011

Establishment of Standard Girders
With iron plate girders, a method to decide the spanarrangement by designing multiple types of girders of a set
length and combining those was adopted at a relatively earlystage. Principal engineer Pownall, who arrived in Japan in
1882, added newly designed girders to existing designs,
standardizing six types of plate girders with clear spans of
20 to 70 ft in 10-ft intervals in 1885. Later, Pownall designed
20 to 40-ft steel standard plate girders in 1893 and 1894
with the main material changed to steel. These British-styleplate girders have features such as wide cover plates around

Ibigawa Road Bridge (1887) converted from Tokaido Main Line Railway Bridge(Author)the entire circumference at the top, bottom, front and backends, T-shaped stiffeners to reinforce web plates that curved
around top and bottom ends to avoid angles and riveted tocover plates, forge-welded struts and stiffeners connecting
the right and left girders to form a unified square shape, andno diagonal members. Girder height was also smaller thanlater American-style plate girders.
The engineer Bunzo Sugi designed 20 to 80-ft steel
girders to American standards in 1902 as new standard
girders, marking a change from British to American style.
After nationalizing private lines in 1906–07 the government
railways worked to unify standards. Bridge live loads
followed the Cooper’s E33 standard, and improved standard
plate girders were designed in 1909. Standard girders with

Oigawa Bridge, Tokaido Line with 200-ft truss for live load E45 

cast-iron supports were designed in 1919, and even larger(Author)standard girders were designed the following year for theE40 live load. These structures hardly changed even after
the 1928 adoption of the metric system and were used until

100-ft girders. A total of 22 were used on bridges over thethe end of riveted structures.

Tonegawa, Ibigawa, Nagaragawa, and Kisogawa.

The girders of larger spans were truss structures. Many

Then, a total of 90 double Warren truss girders of thewith the almost 100-ft span adopted for bridges on the Osakasame skeleton whose wrought iron main members wereto Kyoto section were produced as standard girders for the

replaced with steel members, were manufactured in England

Tokaido main line, Nippon Railways, and others. Trusses ofand erected in the Hakone area, crossing the Fujigawa,the same design were produced in steel from about 1893

Oigawa, and Tenryugawa on the Tokaido main line, themainly for double-tracking the Tokaido main line.

Saigawa on the Shin’etsu Line, the Tonegawa on the Joban
Line, the Tonegawa on the Ryomo Line, and the Kiso,

Appearance of 200-ft Trusses

Nagara, and Ibigawa on Kansai Railways.

Pownall designed trusses with a span twice that of Warren

for a long time. The government railways did not adopt, truss

pony trusses (100-ft long with clear span of some 94 ft) togirders with spans of more than 200 ft until three trusses withbuild bridges on the Tokaido main line from Tokyo to Kyoto.

300-ft spans were imported from the USA in the late Meiji

These new trusses had a clear span of 200 ft (60.96 m) toperiod and installed on the Chuo Line and Ou Line.

This 200-ft span became standard for Japanese railways

cross large rivers. Unlike with previous procedures, Pownall

Kyushu and Hokkaido

drew the detailed designs and sent them to T. R. Shervington
in Britain for checking before making some adjustments andordering manufacture by the Patent Shaft and Axletree Co.

Following the early example of the government railways,

Ltd., in Great Britain. The entirely wrought iron pin jointed

private railways in Honshu used British-style bridges,

double Warren trusses (called truss girder or lattice girder

but the early Kyushu Railways were of German design

at the time) had crossbeams placed at equal intervals on

and manufacture because the Chief Engineer was

lower chord members and were surface bearing as with

Hermann Rumschoettel. The Chitosegawa Bridge over theJapan Railway & Transport Review No. 57 • Mar 201152

Breakthrough in Japanese Railways 8

Usui No. 3 Bridge of old Shinetsu Line (1892), now used as foot bridge for walking trail (Author)

Chikugogawa on the first section had 100-ft and 150-ft

overcome the steep 66.7‰ grade; construction started withspan parallel cord pin-jointed Pratt trusses made by Union.

the section opened in 1893. All the bridges built on the steep

Later truss girders were all Harkort pin-jointed bowstring

grade were all-brick arches. The No. 3 Usui Bridge consists

truss girders developed for underdeveloped countries withof four arches, and is the largest in the section at 91-m long

100, 150, and 200-ft spans. Materials and dimensions wereand 31-m high, making it Japan’s highest brick bridge.

metric, and they were promoted as not using rivets at the

Switch from British to American Style

worksite, allowing easy assembly. They had a small design
live load and could not handle the rapid increase in transportvolumes and heavier locomotives, so they were removed

Imperial University Professor Canadian J. A. L. Waddell andfrom trunk lines relatively early.

Pownall debated the relative merits of British and American

In Hokkaido, American engineers were hired for railway

style bridges in a Yokohama English language newspaper

construction so wooden bridges were used widely in thein 1886, sparking a war of words over British and American

fashion of a pioneer railway and there were also wooden

style bridges. As the number of Japanese who had studied

trusses. American iron pin-jointed trusses (100 and 150-ft

in the USA increased and Imperial University graduatesspans) were used in 1882 on the Horonai Railway.

became more professionally active, the movement away fromexclusively British methods gained momentum. In 1893, theUsui Pass Brick-Arch Bridge

Director of the Railways Agency changed from Masaru Inoue

Another remarkable job by Pownall was the construction ofstudied in the USA. The influential Pownall returned to thethe steeply graded section at the Usui Pass on the Shin’etsu

UK in 1896. As a result, bridge design changed graduallyLine between Yokokawa and Karuizawa. In selecting thefrom British to American style.

who had studied in Britain to Soichiro Matsumoto who hadroute for this section, Pownall stressed that it should be built

The government railways commissioned prominent

at the standard steepest gradient (25‰) because it was

American bridge engineers Theodore Cooper and Charles

part of the trunk line. However, the terrain from Yokokawa to

Conrad Schneider to design new truss girders to handle

Karuizawa was all up grades, so the pass could not simply

the heavier trains. A total of ten types of standard trusses

be tunnelled and it was impossible to build a standard gradewere designed: 100, 150, and 200-ft clear span deck andline. Japanese engineers decided they would need to use athrough trusses; 100 and 200-ft through trusses including

special method employing the Abt rack and pinion system tothose for double track; a skew 200-ft through truss and 300-

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Japan Railway & Transport Review No. 57 • Mar 2011

ft through trusses. From 1899, most were made in the USA

It would be 1907 before the government railways

and were installed on lines under construction, lines being

imported 300-ft trusses and erected them on the No. 1 anddouble-tracked, and as replacement bridges on the Tokaido

No. 2 Kisogawa Bridges on the Chuo Line.
At the end of this period, a new truss design for

main line.
Some private railways started using American style

cantilever designs was adopted for three bridges on thebridge girders from 1896. Private railways in the Kansai

Ban’etsu Line over the Aganogawa opened in 1913 andregion predated government railways in adopting spans

1914. The Amarube Viaduct opened in 1912 on the San’ingreater than 200 ft. In 1899, Hankaku Railway and Kiwa

main line was a viaduct with high trestle piers designed by

Railway imported 250-ft class pin-jointed curved cord

Seiichi Furukawa who had been Pownall’s assistant. Trestle

trusses with subdivided panels from the USA. The samepiers were imported from the USA and the girders wereyear, Kyoto Railway imported 280-ft pin-jointed curved

made in Japan. The bridge was removed in 2010 when acord Pratt trusses from the USA and installed them on the

new bridge was completed.

Hozugawa Bridge.

Switch to Rivet Jointed Trusses andDesign and Manufacture in Japan
Railway works started manufacturing plate girders early on in
Japan, but truss girders were imported from Britain and the
USA for a long time by the government railways and Railway
Agency. The last imported trusses were made in 1913.
Imports were relied on for truss girders because thetension members called eye bars for pin-jointed trusses
were hard to manufacture. However, from about 1905, theGovernor-General of Taiwan Railways, commissioned massproduction in Japan of pin-jointed truss girders designed
by Cooper and Schneider that were the same design as
those of the government railways. This suggests that the
government railways probably did not trust private-sector
American pin-jointed truss girders of Ibigawa Bridge (1900) on Tarumi
Railway(Author)Former Amarube Viaduct constructed in 1912 and dismantled in 2010 Japan Railway & Transport Review No. 57 • Mar 2011

(Author)54

Breakthrough in Japanese Railways 8

manufacturing technology. American style pin-jointed

established in 192 0. Standard girders switched totrusses of the time were clear in theory, but live loads are

metric in 1930 and had eight spans from 8.2 m to 31.5

larger than dead weight for 300-ft or shorter trusses adopted

m corresponding to live loads of KS18, 15, and 12. KS18

by Japan. As a result, large sway and vibration commonlycorresponds almost identically to E40, and likewise KS15 todamaged various parts, such as eye bars. Soji Okoto, who

E33 and KS12 to E26.

had studied in Germany, realized that German truss girder

Attempting New Forms

panel points were all rivet jointed. Upon returning to Japan,
he proposed that standard trusses be rivet jointed insteadof pin jointed, and he set about producing them in Japan.

Various new structures were designed and built from the

The first were designed at live loads for standard gauge

1920s to 1930s, a period when many standard bridges(1435 mm) trunk lines (E45) to replace British 100 and 200-ft

were constructed.

trusses on the Tokaido main line designed in 1911 and 1912.
While some were manufactured in the USA, most were the

Rigid frame bridges

first truss girders commissioned by the government railways

Rigid frame bridges that merge plate girders and steel

from private-sector manufacturers in Japan. Electric railways

columns were designed and built in urban areas. These

were soon opening in quick succession in large urban areas,

include the Yodobashi Overbridge (1922), Iidabashi

such as Tokyo, Osaka, and Nagoya, and American style tall

Underbridge (1926), and Suidobashi Underbridge (1931).

and light rivet jointed trusses were adopted with design andmanufacture completed in Japan. The first is believed to be

Trestlesthe Yodogawa Bridge of Hanshin Electric Railway in 1905.

Bridges with the same truss structure piers as the 1912

The different standards of the various railways were

Amarube Viaduct—trestle piers—were erected over deep

unified after the 1906-07 railway nationalization and an

mountain gorges. Five bridges of the former JNR used thisorganization specializing in design of railway infrastructure

structure, including the Tateno Bridge (1928) and No. 2

was established. Bridge design live loads were set as

Hirosegawa Bridge (1931).

Cooper E33 in 1909, and new standard girders meeting that

The Nakakosawa Bridge on the Koya Line of Nankai

specification soon appeared. There were seven types ofElectric Railway is a Greek π-shaped viaduct combining

new standard girders for deck plate girders from 20 to 80 ft.

trestle piers and truss girders. It is the only railway bridge ofStandard through plate girders were established in 1910 ofthis type still standing today.

the same span and live load.

Curved girders

The first design specification for steel railway bridges forgovernment railways was established in 1912. They followed

The Manseibashi Underbridge (1928) on the Chuo Line had

the American standards, and the basic specifications did

curved girders matching the line curve radius.

not change even with the switch to the metric system.

In 1932, a truss girder was designed and constructed

Cast-iron shoes were added to the 1919 designthat was bent at the panel points to match the 300-m radius

specifications, which was an update of the 1909 version.

of the line at the Iyogawa Bridge on the Dosan Line.

Deck plate standard girders with a live load of E40 were

Suidobashi viaduct (1931) over Hakusan Street (Author)Manseibashi bridge on Chuo Line 

55(Author)Japan Railway & Transport Review No. 57 • Mar 2011

Yodogawa Bridge (1928) on Kyoto Line of Kintetsu Railway (Author)

Sumidagawa Bridge on Tobu Line (Author)Yoshinogawa Bridge on Kotoku Line (Author)

Sumidagawa Bridge (1932) on Sobu main line (Author)

Huge truss girders

various road bridges spanning the Sumidagawa. Structurally,

Nara Electric Railway’s (now Kintetsu Kyoto Line) Yodogawa

its hinge part stands out. Cantilever truss structures were not

Bridge opened in 1928 had double-track curved cord Prattused by the government railways.

trusses with subdivided panels (Pennsylvania truss). It wasvery large, with a 540-ft (164.6 m) span, radically surpassing

Continuous truss girders

the government railway’s largest bridge, a pin-jointed single

In 1932, three three-span continuous trusses with 71.2-

track truss with a span of 306 ft 3 in (93.3 m). That span is

m spans and a 45.3-m span truss were installed at thestill the largest single span truss. The original bridge plan

Yoshinogawa Bridge on the Kotoku Line. They were thewas an ordinary plate girder bridge of several girders, butearliest full-scale continuous trusses and drew attention

the bridge location was at an army river-crossing training

along with piers using pneumatic caisson foundations.

ground, and the commander would not allow a bridge pierthere. His unreasonable demands, rather than technicalArch bridges

necessity, forced construction of huge truss girders neverJapan’s first steel arch (solid rib) for railways was theseen before in Japan. The bridge featured a design by

Oshikabuchi Bridge on the Otaki Forest Railway that

Shigeki Sekiba, imported American steel, manufacture at

opened in 1923. However, it was a 762-mm gauge lightthe Hyogo Works of Kawasaki Shipyard, and construction by

railway bridge. It was followed by construction of four steel

Obayashi Corp., boasting a high technical level and scale

bridges from 1926 to 1930 for a dedicated track (762-mm

equal to projects in the USA. It does not appear in the history

gauge) for transporting materials to build the Kurobegawa

of JNR, but cannot be overlooked.

hydroelectric power station. The bridges are the old Kurobe
Bridge (spandrel braced balanced arch), Moriishi Bridge

Cantilever truss girders(solid rib arch), Atobiki Bridge (spandrel braced arch), andTobu Railway’s Sumidagawa Bridge (1931) is a cantilever half

Kanetsuri Bridge (spandrel braced arch) of today’s Kurobe

through truss, well formed and standing on a par with theGorge Railway.

Japan Railway & Transport Review No. 57 • Mar 201156

Breakthrough in Japanese Railways 8

S pecial - use bridges include
prefabricated military portable truss
bridges developed by the army. They
could handle various spans and loads
by assembling large fully welded
structural units that could be moved
without heavy machinery.

Movable bridges
The first railway movable bridge
where the bridge girders move was
the Wada Swing Bridge constructed
in 1900 on the Wadamisaki Line in
Kobe. No other bridges of that typewere constructed for a while, but 14
were eventually built between 1927
JR Freight’s Suehiro Bridge at Yokkaichi–bascule movable bridge (1931)

(Author)and 1960 mainly on harbour port lines.
They were bascule and lift types, butthere were no swing type bridges.
The designs were from Yamamoto

A spandrel braced balanced arch was erected for

Komusho headed by Utaro Yamamoto and from the Ministryordinary railways in 1928 at the No. 1 Shirakawa Bridgeof Railways. The largest movable bridge in Japan was the lifton the government railways’ Takamori Line (now Minami

type Chikugogawa Bridge on the Saga Line; it now serves

Aso Railway). That was the first government railways’ steel

as a footbridge after the railway line was abandoned. The

arch bridge with a span of 300 ft (91.4 m) but it did not

only movable bridge still serving as a railway bridge is theexceed the existing largest span. In 1937, a spandrel braced

Suehiro Bridge (1931) at Yokkaichi Port. It is owned by JRbalanced arch with an arch span of 112 m was designed for

Freight and was designated a national important cultural

the present day Tadamigawa Bridge on the Tadami Line. It

property in December 1998.

opened in 1941, setting a new record for the largest span.
The Sumidagawa Bridge (1932) on the Sobu main line
was Japan’s first full-scale deck-stiffened arch bridge, andits central span of 96 m set a new record for the largest
government railways’ span. The Matsuzumicho Underbridgeon the same line was a braced rib tied arch that also opened in
1932. The two bridges on the Sobu main line had a presence
on a par with road bridges spanning the Sumidagawa.

Welded structures
Use of welding technology on railway bridges started in 1931
as a method to reinforce existing plate girders while keeping
the bridge in operation. Braces were welded to upper andlower flanges. In the 10 years from 1931 to 1940, some 1300
girders were reinforced by welding.
While not a railway bridge, an overbridge wasconstructed in 1935 at Tabata Station in Tokyo as the first

Junichi Konishi

full-scale welded bridge. It was a rigid frame cantileverProfessor Konishi is professor emeritus at Shinshu University. He
earned his PhD in engineering at Kyoto University in 1979. His related
publications are: Japan Society of Civil Engineers (ed.) ‘A Survey ofHistoric Iron and Steel Bridges in Japan 1873–1960’, 2002 (http://library.jsce.or.jp/jscelib/committee/2003/bridge/brtop.htm); andNaruse Teruo (ed.) ‘Historic Iron and Steel Bridges in Japan’, Tokyodo Shuppan, 1994 (co-author) Japan Society of Civil Engineers (ed.)‘What has been built in Japan?–Exploration of historical infrastructure
in Japan’, Sankaido, 1995.

bridge with unified girders and piers, having span lengthsof 40.5 + 53.0 + 40.5 m, making it the largest in the world at
the time.
The first fully welded railway bridge used a small plate
girder with a 7.2-m span erected on a test basis in 1941 forthe Kabe Line No. 1 Yasu Bridge. It is still in use today.

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Japan Railway & Transport Review No. 57 • Mar 2011