No. 32
March

2011

A Joint Publication of The Japan Iron and Steel Federation and Japanese Society of Steel Construction

Special Issue

Japanese Society of Steel ConstructionJSSC President Prizes 2010
Development and Application of New Jack-down Demolition Method for High-rise Buildings
Prize Winner: Kajima Corporation
The demolition of high-rise buildings has thus
far been carried out by starting from the upper
stories and working downward to the lower
stories. In the newly developed “jack-down
method,” jacks are installed just beneath the
1st-floor columns, and the building is demolished beginning from the lowest story. Continuing upwards, the columns of each floor are
cut and the floors are successively jacked
down. In order to secure seismic safety during
demolition, a reinforced-concrete “core wall”
and a steel-structure “load transfer frame” arenewly installed inside the building.
This new method was applied in the demolition of a 20-story office building, resulting in
confirmation of the following merits:● Demolition worksite was constantly surrounded, leading to less scattering of noiseand dust.
●D emolition occurred only on the ground,
thereby eliminating concern in neighboringareas.
●W aste matter was easily separated and recycled as useful resources.
●R ecycling rate increased to 93% as opposed

March 24, 2008
May 27, 2008
Photo 1 Demolition of 20-story office building

to about 55% using the conventional method.
● Recycling rate including that for the building structure reached 99%.
● High-rise work safety and safety from falling objects were improved.
● Time and labor required to unload demolished materials using tower cranes were reduced, leading to improved work efficiency.
The demolition cost of the new method is
5~10% greater than for the conventional meth-Fig. 1	Comparison of Conventional and New Demolition
Methods (Building Section)
Entireexternal
Demolition
scaffolding machinery High-strength
steel support

July 25, 2008

od, but the demolition term can be reduced byabout 15%. Using the new method, the demolition work is shorter, thereby allowing thesubsequent new building construction to startearlier. Accordingly, because completion of
new buildings can be hastened, economical
advantages are realized throughout the entire
process from demolition to new building construction.
While the building targeted for demolition
was only a 20-story steel moment structure,extensive studies are underway to improve
work efficiency and to reduce costs, with thegoal of enhancing the general applicability of
the jack-down method demolition for eventaller buildings in the future.

Fig. 2 Core Wall and Load Transfer Frame
ColumnCore wall
Load transfer frameCore wall Load transfer frame

No. 2 building
Core wall

Core wall

Heavy machineryfor demolishingbuilding structureJack Load transfer Core wall
frame

Hydraulic jack• Uplifting of heavy machinery to the• Installation of jack on lower floor
upper section; crushing subsequently• Structuring of core wallfrom the upper floor• Crane, high-strength steel support and• Demolished material: Throwing down
external scaffolding are unnecessary
through temporary opening• Demolition subsequently from the• Crane, high-strength steel support andlower floor
external scaffolding are necessary• Work on the ground surface• Demolition subsequently from theupper floor• High-rise worka) Conventional methodb) Newly-developed “jack-down method”

1 Jack-down Demolition Method• Installation of temporary RC-structure “core wall” inthe center of the building to bear horizontal force
during earthquakes• Installation of steel-structure “load transfer frame” inthe four-corner columns to surround the frame• In case of an earthquake occurrence, the core walland the aboveground steel frame are integrated via
the load transfer frame to secure the seismic
resistance similar to that of the building before
demolition.
• Structuring of thoroughgoing fail safe system bymeans of seismoscope and emergency earthquake
alarming system

JSSC

Flat Plate Supported by Steel Bar Columns and Steel Capitals
Prize winners: Takenaka Corporation and Nippon Steel Corporation
Generally, building designers and owners tend
to dislike heavy columns and any structure that
protrudes from beneath the flooring slabs. In
response to this, Takenaka Corporation andNippon Steel Corporation have jointly proposed a new framing method: flat plate framing, which uses steel bars as columns to reducecolumn diameter to a minimum, and steel capitals that are embedded in the floor slabs (Fig.
1).
The new framing method is highly regarded as an approach to realizing indoor spacesthat offer enhanced transparency. This method
already has a richly documented record of application―40 examples of use in the construction of buildings of wide-ranging size and purpose (Photo 1).
Three technologies have been adopted tobring about the new framing method:
Very Slender Steel Bar Columns
The most slender columns available using
contemporary technology are steel bars. In order to easily and legally apply steel bar col-Fig. 1 Flat Plate Supported with Steel Bar Column and Steel Capital
Conceptual drawingof the new framing

Conventional flat slab and flat plate structures
RC column

RC column

RC column

RC flat slab

RC flat slab

RC support plate

RC capitalabFlat slab structure

N Sports Zone club house

RC flat plate

RC flat plate

Steel capitalc

Fukuyama; 7 stories, 2 basements●-130 mm

K University No. 13 Building
Kobe●-140 mm●-140 mm

FIC Tower

Fukuoka; 42-story high-risehousing (1 basement)

On-site Column-to-Column Joiningof Steel Bar Columns
In applying the new framing method in theconstruction of multi-storied frames, one important and unavoidable technological task
was on-site column-to-column joining.
Regarding the joining position, because theadopted coating finish lacks fire protection,joining must be undertaken within the slab inorder not to expose the joining surface.
As for the joining method, several approaches such as partial penetration weld joining, weld-free spherical-support bearing joining and high-strength bolt flange joining havebeen adopted (Fig. 2).

dFlat plate supported with steel bar
column and steel capital

Flat plate structure

Z Hospital

Kobe; 1 story

Steel bar column

umns, Nippon Steel obtained material approval in January 2006 for large-diameter roundsteel bars for building structures, which was aremarkable event that anticipated the stricter
revisions of the Building Standard Law of Japan that came after 2006.

●-200 mm

O University of Economics: C Building
Osaka; 7 stories

K University No. 13 Building: Interior view●-140 mmSlab-embedded Steel Capitals
Slab-embedded steel capitals constitute thebasic technology of the new framing method.
The dynamic properties and the fracture mechanism of the current framing process weremade clear by means of horizontal and verticalloading tests and analytical studies focused on
establishing the design method and the design
criteria. Further, the new framing method has
undergone technical appraisal (GBRC performance appraisal No. 09-03) by the General
Building Research Corporation of Japan,
which has been essential for the practical andwider application of flat plate framing supported by steel bar columns and steel capitals.
Fig. 2 Example of Slab-embedded Joint
Weld joining●-150 mm
AOP Tower

Fukuoka; 25-story high-rise housing

Flange joining
Partial penetration welding

Strong Building

High-strength bolt
joining

Kobe; 8 stories

Strong Building: Interior view
Mobil parking lot●-200 mm●-200 mm●-200 mm

Photo 1 Examples of applications in buildings with various sizes and uses

Photo 2 Example of steel capital (site welding)
Flat Plate Supported by Steel Bar Columns and Steel Capitals 2

Development and Practical Application of BHS: High Performance Steel for Bridges
Prize winners: C hitoshi Miki, Research Center for Urban Infrastructure of Tokyo Institute of Technology;
and Hirofumi Kawasaki, Research Group on Steel for Bridges of the Japan Iron and SteelFederation
BHS (bridge high-performance steel) is a material in which the strength, fracture toughness,
weldability, workability, weathering resistance and other performances required forbridge construction have been improved beyond conventional levels. In BHS, the performance values of the various characteristic features required for bridges have been enhanced
to optimum levels.
The remarkable progress in thermo-mechanical control process (TMCP) technology
has enabled finer control over the microstructures of recent structural steel products, which
has brought about enhancements in the material qualities of these products. Specifically,
these include improved weldability due to optimization of the carbon equivalent and weld
crack sensitivity composition, minimization of
impurities, and improvements in thicknessand width-direction properties—in addition to
improved mechanical properties such as higher strength and higher fracture toughness.
Consequently, the utilization of steel products
making the most of these excellent properties
is anticipated, and efforts are being made towards their development and practical use.
Development Concepts for BHS
Two concepts were worked out for the development of BHS.
● To develop high-performance steel that reflects the development of iron- and steelmaking technology in Japan, and to provide
steel with higher strength, toughness andweldability by using the latest TMCP technology to produce finer microstructure● To contribute to the development of steel
structures by maximizing the use of highperformance steel offering high economical
advantages for bridge design and construction, as well as international com­pet­it­ iveness
Notable progress in bridge steel products
can be seen in the increasingly finer crystallization of microstructures (Photo 1). The latest
BHS uses controlled rolling and cooling technologies to offer materials with a compatible

Photo 1	On-site welding of truss joints employing BHS (courtesy: Kawada Industries)

Photo 2	En-block installation of the lower truss
section with fully welded joints (courtesy: Kawada Industries)

mixture of weldability, strength and toughness.
Goal of BHS Development
In developing BHS, we noticed that lighterand more efficiently structured steel bridges
can be designed by using BHS with higher
strength and weldability than are found incommonly used SM steel products (JIS), andthat the manufacture of bridge members canbe streamlined by capitalizing on improved
welding operations.
Practical Application of BHS
Innovative and economical steel bridges are
anticipated by combining favorable membermanufacturing efficiencies (weldability, workability, etc.) made possible by the use of BHS
with new designs that make the most of thehigh strength of BHS. For the Tokyo Gate
Bridge (provisional name) that is now underconstruction, diverse new technologies havebeen adopted in its economical design, such as
fully welded joint for the continuous steel truss
bridge, which employs both BHS and load andresistance factor design.

Photo 3	Artist’s sketch of Tokyo Gate Bridge(courtesy: Tokyo Port Office, Ministry ofLand, Infrastructure, Transport andTourism)

Table 1 Development of BHS (Bridge High-performance Steel)Fig. 1	Transition of Microstructures of
Steel Products for Bridges

1882: Microstructure of
wrought iron

1925: Microstructure ofsteel by ingotmolding method

1994: Microstructure ofrolled steel for
welded structures

Microstructure of BHS

3 BHS: High Performance Steel for Bridges

Year

Content

1994~2000

Basic Study of BHS application potential for steel bridge member

2003

Proposal of BHS (BHS500, 700)

2004

BHS Registration in New Technology Information System (NETIS) of Ministry ofLand, Infrastructure, Transport and Tourism

2005

Establishment of specifications for BHS500, 500W, 700W by the Japan Iron andSteel Federation

2006

First application in Nanboku Suiro Crossing Bridge (about 1,200 tons)

2007

Application in Tokyo Gate Bridge (about 17,000 tons)

2008

Official notice of JIS G3140 for SBHS500, 500W, 700. 700W

2009

Specifications for civil engineering materials (Construction Bureau, Tokyo Metropolitan Government)
Revision of Steel and Composite Structures, Design Standards and Commentaryfor Railway Structures (Railway Technical Research Institute)JSSC

D-Runway at Haneda Airport: Construction of the World’s First Steel Jacket-type Runway
Prize Winners: Joint Venture of D-Runway Construction Project; and Tokyo Airport Construction Office,Kanto Regional Development Bureau, Ministry of Land, Infrastructure, Transport and Tourism
The D-Runway, the fourth runway of Tohumidity with a dehumidifying system,
structure having an extremely spacious
kyo International Airport (Haneda Airand lining structures above the tidal andsurface area.
port), was constructed in an area offshore ● In order to secure sufficient fatigue
splash zones with stainless steel that isfrom the existing airport. Because oneresistant to seawater corrosion.
strength to accommodate about 12 milthird of the entire runway lies within thelion takeoffs and landings of aircraft overmouth of the Tama River, the D-Runway
a 100-year service life, FEM analysis Photo courtesy (front cover, page 4, back cover)
Joint Venture of D-Runway Construction Projwas designed as a hybrid structure: rewas used in conjunction with conven- ectclaimed land and a pier structure that entional design methods to check fatigue insures uninterrupted flow of the river. The
the special section. Further, two new appier adopted a first-of-its-kind steel jacket
proaches were fully introduced for memstructure made for use in airport infrastrucber manufacture: improving
ture.
weld fatigue strength by means Fig. 1 Entire Structure of D-Runway
Because the pier section has a spaciousof the ultrasonic impact treatflat area of about 520,000 m2, many restricment method (UIT) and contions were imposed on its construction: theducting non-destructive inHANEDA Airport
production and installation of a vast numspection by means ofTama riverber (198) of jackets (steel products: about
ultrasonic automatic flaw de260,000 tons) and 1,165 steel pipe piles
tection (AUT).
(about 90,000 tons) in a relatively short pe- ● Advanced corrosion protection
riod, realization of long-term durability forsystems for steel products were
D-RUNWAY
as many as 100 years, ensuring river flow,
adopted to optimize LCC andand providing fatigue strength capable ofmaintenance: cladding the up1100 m
2020 mwithstanding repetitive aircraft landings
per girder section with titaniJacket type pier area
Reclaimed area
and take-offs. In spite of these restrictions,um cover plates, controllingthe new D-Runway
Fig. 3	Integration of Upper and Lower Jackets
was completed only in Fig. 2 Jacket Structure
three and a half years.
Upper girder
Titanium cover plate
The pier jacket
struc­ture offers the following main features:● The jacket consistsof an upper steelLeggirder section and alower truss section,
the latter of which
was designed without diagonal memStainless steel lining
Bracebers in the areas
above sea level. This
Fig. 5 Full View of Jacket-type Pierconfiguration
en- Fig. 4 Construction of Pier Section
sured river flow, reduced to a minimum level any
restrictions on thelower structure attributable to temperature-induced
expansion/contraction of the upper
structure, and madepossible a continuous
integrated
D-Runway at Tokyo International Airport 4

Thesis Prizes 2010
Research on the Flexural Shear Behavior of Short-span Beams with Preceded Shear Yielding
Prize winner: Yukihiro Harada and five other members
Yukihiro
Harada1995: G raduated from Graduate
School of Engineering,Tokyo University
2007: P rof., Graduate School ofEngineering, Chiba
University

Following the Great Hanshin Earthquake of 1995, one important goal was to prevent the occurrence ofbrittle fracture and to secure plastic deformation capacity in the beam end welds of square steel tube
columns and H-shape beam connections. This was attempted by disseminating and putting into practical use the haunched flange, which expands beam-end flanges in order to relax weld stress. However,for beams having small spans compared to their beam depth, cases exist where it is difficult to conduct
member design that allows flexural yielding of beams to precede the fracture of beam-end connections,even using the width expansion method. This has been a major problem in beam-end fracture prevention design.
To resolve this problem, the author et al have proposed a new beam-end fracture prevention design
method that uses shear yielding preceding beams that induce shear yielding in the beam webs prior to
flexural yielding of the beams in order to relax stress in the beam-end welds. Then, a series of cyclicloading tests was conducted using shear yielding preceding beam specimens, including beam end welds
to prove the validity of the new beam-end fracture prevention design method.

Fig. 1	Example of Ultimate Stateof Beams with Preceded
Shear Yielding (Test
Specimen F-1)

Fig. 2	Example of Relation
between Cycling Loadingand Deformation ofBeams with Preceded
Shear Yielding (Test
Specimen F-1)

Study on Retrofit Measures in Welds of Vertical Stiffener Cutting Treating of the Semi-circular Notches in
Orthotropic Steel Deck
Prize winners: Yoshihiko Takada and three other staff of Hanshin Expressway Company Limited
Yoshihiko
Takada1989: Graduated from Faculty ofEngineering, Osaka City
University
1990: Entered Hanshin Expressway Public Corporation
2010: Construction Technology
Section, Hanshin Expressway Company Limited

Fig. 1	Semi-circular
Notching

5 Thesis Prizes

Of fatigue cracks that occur in orthotropic steel decks, cracks in the fillet welds of deck plates and vertical stiffeners of main girder web are caused by concentrated local stress due to restrict deck deflection
deformation by vertical stiffeners. This paper presents the results of studying on retrofit measures in
welds of vertical stiffener cutting treating of the semicircle notches, to ease the concentration of stressin welds (Fig. 1).
In FEM analysis, it was observed that the occurrence of stress is reduced by providing semi-circularnotches to about 1/2 at the deck-side toe and about 1/3 at the vertical stiffener-side toe.
Fatigue tests using specimens show the propagation of cracks slowed to almost nothing after notches are provided. In cases where a stop hole was provided for deck-penetrating cracks, the cracks showedno further propagation. The measurement stress on existing orthotropic steel deck is reduced to about
40% at the deck side and to about 30% at the vertical stiffener side after notches are added.
The current research makes clear that weld stress conditions are improved when notches are provided to improve fatigue durability and, at the same time, that the propagation of existing cracks can besuppressed.
Fig. 2	Crack Occurrence
and Fatigue
Strength to Prevent FractureJSSC

Basic Experimental Study on Seismic Uplift in Single-story Structures with Single-axis Asymmetry
Prize winners: Tadashi Ishihara and two other members
Tadashi
Ishihara
National
Institute forLand andInfrastructureManagement,
MLIT

Tatsuya Azuhata
National Institute for Land andInfrastructure Management,
MLIT

Mitsumasa Midorikawa
Hokkaido University

The authors have conducted research that notices the effect of uplift on seismic response reduction. We
conducted shaking table tests with the aim of clarifying the effect of eccentricity on seismic response
reduction that had not yet been clarified.
In the preparation of the test specimens, due care was paid to the following three points (Fig. 1):● Materialization of the assumption that the floor is rigid in its own plane● Securing column rigidity and strength against collision and impact at the time of landing● Compatibility for both specimen downsizing and the appropriate natural period
The test specimens consisted of rigid columns and flexible beams in a simple single-story structure
containing only four columns.
Two specimen models were adopted: a non-eccentric model (N) and a model with single-axis eccentricity in the short-side direction (E). The eccentricity ratio of the E model was set at 0.48, a comparatively high level. The natural period in the short-side direction was 0.45 seconds for N and 0.54
seconds for E.
Fig. 2 shows the maximum response value, setting the average story drift angle Rm (normalized bymultiplying by ω2) of the short-side structural frames on the x-axis. It became clear in the current research that the average of the shear forces is nearly identical regardless of whether the model is eccentric or non-eccentric and regardless of the kind of seismic wave, and that uplift motion tends to limit theincrease of the torsional angle to a certain level.

Fig. 1 Test Specimens

Fig. 2	Maximum Response Value to Average
Story Drift Angle Rm

Column formeasurement
Connection

Connection

Pulse

El Centro

Kobe

Hachinohe

ColumnGauge

Specimen(c) Column head connection
Column formeasurement
Flexible beam(flat bar)

Joining by
one bolt withdouble nuts

Laser(displacement
sensor)CircularcolumnHemi-sphere

Bearing
Foundation Excitation
beam
direction

Excitation
direction(a) Plan(b) Elevation

Foundation
beam

Inverted cylindrical dent provided
for circular column(a) Average shear force of the short-side
structual frames(b) Tortional angle(d) Bearing

Evaluation on Behavior of Fatigue Crack through Thickness in 3D Structures by XFEM Analysis
Prize winners: Kazuki Shibanuma and four other members
Kazuki
Shibanuma

2010: Graduated from Department of Civil and Earth
Resources Engineering,
Kyoto University
2010: A ssistant Professor,
Department of Systems
Innovation, The Universityof Tokyo

Many fatigue crack damages have been reported in aged bridges. It is therefore urgently required toclarify the causes of these damages and to rationalize bridge maintenance. Numerical simulation of thefatigue crack propagation behavior is effective to solving these problems.
Cracks can be modeled independently from meshes by using the extended finite element method(XFEM). In this study, an code was developed that can easily and efficiently simulate crack propagation by implementing the PU-XFEM into general-purpose FEM analytical software. The PU-XFEM is
the reformulation of the XFEM solving the incompleteness caused by the original XFEM. Further, thevalidity of the code was confirmed by simulating the propagation of fatigue cracks in the intermediatecross beam of I-girder bridge and the steel floor deck specimen using bulb rib. The results of fatigue
crack simulations showed a good agreement with test results.
Fig. 2	Numerical Model of the
Orthotropic Steel Deck
Specimen

Fig. 3	Comparison of the Results of Fatigue Propagation Path in the Numerical Simulation and Fatigue Test

Fig. 1	Modelingof Crackin the
PU-XFEM

Thesis Prizes 6

Steel Composite Structures andRailway Facilities
Railway Construction in Japan
Railways in Japan have a total length ofabout 20,000 km and are operated by six
passenger railway companies and one
freight company, which were privatizedand divided from the government-owned
Japan National Railways in 1987. About
2,200 km of these railway lines are operated as a network of high-speed passenger
lines, the so-called Shinkansen. Shinkansen is an advanced system compared withconventional railway systems using narrow gauge lines. For example, Shinkansen
basically adopts the standard gauge andnew signal- controlling systems. The first

515 km of Shinkansen was opened to traffic in 1964, the year of Tokyo Olympics, as
the first high-speed railway in the world.
Since its opening, new high-speed lines
have steadily been constructed until today.
Japan has a total population of 120 million in its narrow land (1/25 of the UnitedStates). Because of such situation, construction of Shinkansen has often faced severe conditions relating to the work space.
Especially for bridges crossing rivers,
roads and railways, it is not too much to saythat the structural type of these bridges isselected depending on how to erect a
bridge. Therefore, the opportunity has been

increasing in which a bridge structure using mainly steel is selected because of its
excellent performance in installation.
In this article, two topics are introduced.
The first topic is the Matsubara Bridge as
an example of steel-concrete composite
girder bridge, which was constructed undera severe erection condition. The second
topic covers the Hyugashi Station and the
Kochi Station as examples of railway station buildings reconstructed employing
steel-timber composite structures (bothstations are for conventional railways).

Steel-Concrete Composite Bridges in High-speed Railways— Matsubara Bridge: Erection under Severe Conditions —By Kaoru Mitsugi, Special Project Director, Design and Technology Department,
Japan Railway Construction, Transport and Technology Agency
Shinkansen Projects in Japan
As mentioned above, construction of the
Shinkansen lines in Japan has been in progress on a sustained base. An outline of
Shinkansen projects is shown in Fig.1 (a).
The red lines in the figure show the recent
construction of Shinkansen. The extensionof the Tohoku Shinkansen to the northernpart of Japan was completed in December
2010, and that of the Kyushu Shinkansen to
the southern part of Japan is slated in
March 2011. The inauguration of these
new lines means that all regions from thenorthern area of Honshu to the southernarea of Kyushu will be connected by highspeed railways, and thus the mobility is expected to significantly increase throughout
Japan (note: Hokkaido Island will be connected by Shinkansen in 2015).
In the construction of the Shinkansen
lines, steel bridges tend to be selected atsites with severe erection conditions. We
focus on the Matsubara Bridge for which
erection was most difficult in recent bridge
construction for Shinkansen.
7 Steel-Concrete Composite Bridges

Matsubara Bridge● Location and Outline of Structure
Construction of the Matsubara Bridge waspromoted under the severest condition for
the Kyushu Shinkansen bridge projects dueto the constraints posed on construction
space and work time. Fig. 1 (b) shows the
Kyushu Shinkansen scheduled for opening
in March 2011. The Matsubara Bridge wasconstructed near a large station of the conventional line.
Fig. 2 (a) shows an aerial view of thebridge. The new line leads to the downtown of Kurume city, which has a population of more than 300,000 in an area of approx. 200 km2. The construction site is
located between a highly industrialized
area and a densely populated residential
area. Therefore, the new line infrastructure
had to be constructed in a narrow space
above and around the existing railway line
in service. Moreover, the construction site
had a very limited workspace where buildings are overcrowded and existing tracks
are too close. For these reasons, steel-con-crete composite girder bridges and steel
portal frame piers were selected as the
structural type of the Matsubara Bridge, as
shown in Fig.2 (b).
● Structure of Matsubara Bridge
Fig. 2 (c) shows an outline of the structureof the Matsubara Bridge. This bridge iscomposed of a series of steel-concrete
composite box girder bridges and its length
reaches 1,243 m, the longest among otheroverpass bridges on existing railways in Japan. The superstructure consists of a simple box girder, 4 three-span continuous box
girders, and 2 four-span continuous box
girders. The simple girder has the one-box
structure of 3.5 m web height and 85 m
girder length for over passing the broadroad. Other continuous girders have thetwo parallel-box structure of about 2.8 m
web height and 60 m girder length. The
substructure consists of 16 steel portal
frame piers whose span is about 25 m forthe part over passing the existing tracks and6 reinforced-concrete piers for other part.

JSSC
Fig. 1 Railways in Japan (Summer, 2010)

Hokkaido

JR conventional lines (17,600 km)

Asahikawa

SapporoShinkansen under construction (634.2 km)
Shinkansen in service (2,175.9 km)

ObihiroHakodate

Hokkaido Shinkansen(149 km, 2015)

Kyushu Shinkansen(Kagoshima route)(130 km, 2011)

Hokuriku Shinkansen(229 km, 2015)

Kyushu Shinkansen(West-Kyushu route)(45 km)HakataHachinohe

Niigata
NaganoKyushu Shinkansen(North part, 2011)

SendaiShin-Yatsushiro

Fukushima

Nikko

Kyoto

Matsubara Bridge

KurumeTohokuShinkansen(82 km, 2010)

Akita

Yamagata

Hiroshima

KushiroSanyo Shinkansen(1970)

Existing
conventional
line

Kyushu Shinkansen(South part, 2004)

Utsunomiya
NaritaHakataOita
Nagasaki

Nara
NagoyaKumamoto

Kagoshima

Mt.FujiTokyo

KyushuIslandKagoshima-Chuo

Osaka

KyushuKochi Station

MiyazakiHyugashi Station(a) Map of Japanese railways(b) Kyushu Shinkansen

Fig. 2 Matsubara Bridge
Main girder

Matsubara Bridge

South

Portal frame pier

Kyushu Shinkansen
Existing conventional line

Conventional line

North(a) Aerial view(b) View from the existing line

North

80 m

3@60 m3@60 mConcrete pier3@50 m4@60 m

3@56 mSteel portal frame pier (crossing over conventional line)
Composite box girder● Constraints on Space and Time
The superstructure of the Matsubara Bridge
had to be erected over the existing railway
line. The existing line is very busy on
which more than 340 trains run daily. Insuch a tight space, we had to carry out not
only the erection work of the girders andthe piers but also preparation work such as
the assembly of parts for the superstruc-4@60 mSouth

Concrete pier(c) Outline of bridge structure

ture. Furthermore, the erection work above
the existing track had to be finished within
200 minutes in each night work. In this situation, scheduling and management werequite important because working time was
not allowed to be extended and a small
mistake or accident would severely affectthe operation of the existing railway line
operations.

● Balancing Rotation Method for
Cross Beam of Portal Frame Pier
For the erection of the cross beams of theportal frame piers, enough workspace wasunavailable around the existing tracks forthe use of normal erection methods such as
crane-bent erection method. The large
block erection method was also impossible
because the method needed a broad path to
Steel-Concrete Composite Bridges 8

bined with the clevis jacks, which gave aforce toward the rotating direction by thereaction of hydro-clamp device, as shownin Fig.4 (b). A symmetrical setting of two
clevis jacks enabled the control only by applying the slight force.
After the rotation, the cross beam wasconnected to the column on the other sideof the existing track. Field joints of theframe piers were mainly conducted bywelding, but the bolt connection was applied for the joint of rotated cross beams toshorten working time above the existing
tracks.
Fig. 5 (a) shows the assembly work of
the cross beam. Fig. 5 (b) shows the rotation work. The rotation of the cross beam
took only 30 minutes.

approach the site by a large crane. Furthermore, it was required to finish the erection
work in a short night work time, as mentioned before.
The balancing rotation method is a newly-developed method for this construction
work, which enables the erection of thecross beams under such conditions. Fig. 3
shows an outline of the balancing rotation
method. The cross beam was assembled
parallel to the existing tracks in advance.
Fig. 4 shows the rotation devices. After
connecting the assembled cross beam withthe counterweight, the cross beams were
supported by the pivot shoes, as shown in
Fig.4 (a). Then the cross beam was rotatedhorizontally on the column using rotation
devices. Rotation in the narrow space wasavailable by use of the small device com-● Launching Erection Method forSuperstructure
As mentioned, there was no enough spacefor installing superstructure by means ofbent or large crane. The lateral transfer
erection method was also impossible because it needs much time and a yard area
beside the site. In such situations, we applied the launching erection method for the
installation of the main girders.
Fig. 6 shows an outline of erection workof the superstructure. Firstly, the construc-Fig. 3 Balancing Rotation Method
Joint of cross beamCounterweight
Cross beamTemporary
girder90-degree rotation

Rotation device

Column (rotation axis)

Fig. 4 Rotation Device
Circular column

Pivot-shoe jack

Rail for rotation

Jack
Anchor-clevis jig
Clevis jackHydro-clamp
deviceAdjuster jackColumnRail for rotation

tion section was divided into two: 595 m
and 648 m sections. At each section, the superstructure was assembled at the assembly yard on an already constructed neighboring superstructure in a daytime. The
assembled girder was then launched fromthe assembly yard in a nighttime. The main
girders were field-connected by welding
with due consideration for landscaping, reduction of steel usage and ease of launching.
To enable continuous launching, the assembled girders were connected each otherby means of temporary connection (Fig.7(c)) into two large blocks. The connectedgirders were then pushed out from both
sections toward the center of the bridge, as
shown in Figs.7 (a) and (b). The total
launching length is longest among Japanese railway bridges and also longest
among Japanese box-girder bridges including highway bridges. Fig. 7 (d) shows thelaunching devices using caterpillar, whichenabled launching in 120 minutes to pushout each span. The girders included a 5,000m radius curve, but the device was helpful
in controlling the installation position of
the superstructures. To secure the safety
and accuracy of the work, we monitored
the erection force, position, and reaction
force in real time during installation, comparing with the calculated values of frame
analysis in each step of the work. Aftererection, temporary connections were cut
out and the girders were jacked-down into
place as shown in Fig.7 (e).
The assembly work needed about amonth for one-span girder. The launching
work of the girder needed a night for a span
and took 21 nights in total. The total period
of installation took 14 months.

Pivot-shoe jack
Jacking beam

Cross beam(a) Device at the top of column(b) Plan view of device

Fig. 5 Erection of Cross Beam of Steel-frame Pier
Setting beamCounterweight

Cross beam

ColumnCross beam(a) Assembly of cross beam
9 Steel-Concrete Composite Bridges(b) Rotation of cross beam

JSSC
Fig. 6 Launching Erection of Superstructure
TemporaryNorth
connection (T. C.)
T. C.
T. C.
Assembly 1-span
3-span3-span3-spanyard
L=180m
L=150m
L=180m
L=85 mSite 1
L=595 mSouth
4-span
L=240mConnection

Launching

T. C.

3-span
L=168 mT. C.

Site 2

Launching

4-span
L=240 mAssemblyyard

Existing line

L=648 mFig. 7 Launching Erection of SuperstructureSouth

Direction of launching

Erection
Launchingdirection
Main girders(Site 2)Connection
point
Launchingdirection

Main girders

Erection nose
Main girders(Site 1)
North(b) Launching of main girder (bottom angle)(a) Launching of main girder (aerial)

Girder

GirderMain
girderMain
girderLaunching device
MaingirderTemporaryconnection

Sole plate(c) Temporary connection

Successful Completion by Use of
New Installation Methods and Steel
Composite Structures
In the recent construction of Shinkansen
high-speed railways, main concerns in design have shifted from the structure itself toerection methods due to the tough surrounding conditions involved. By applying
the balancing rotation method and thelaunching erection method, we successfully constructed the Matsubara Bridge safely
and on schedule, and without stopping thePier(d) Launching device with caterpillar

service of the existing line. There had beenno bridge in Japan that was constructed
continuously in such a length above existing transportation lines.
Railway use has revived in the light ofenvironmental conservation and needs forenergy-efficiency. Since the inaugurationof the first Shinkansen in 1964, many countries have constructed high-speed railways.
There are also many countries which areplanning high-speed railways. Needs forconstructing bridges in populated areas are

Jacking-down(e) Jacking down of main girder

also increasing. We are sure that our experience obtained in the construction of the
Matsubara Bridge will be quite helpful formany railway planners.
We are striving to expand the application range of steel structures that have excellent construction capability and high durability.

Steel-Concrete Composite Bridges 10

Structural Design of the Hyugashi Station Building
By Mamoru Kawaguchi
Emeritus Professor of Hosei University (Representative, KAWAGUCHI & ENGINEERS)
a new trial technology that is rarely, if ever,found in either station buildings or othergeneral-purpose buildings.

Two new trial approaches have been incorporated in the structural design of the Hyugashi station building in Miyazaki Prefecture.
One is the adoption of a wood-steel
composite structure. The adoption of thisstructure allows the use of Japanese cedar,a distinctive product of Miyazaki Prefecture, as a visually attractive structural material that offers sufficient lightness,
strength, rigidity and durability to form
roof framing members that are capable ofcovering the open spaces of the stationbuilding. Such a structural design would be
impossible using members solely of laminated wood.
The other technology is the adoption oflaminated members consisting of multiple
sections. While there are many examplesof laminated members being used to form
curved monolithic structures, the adoptionof curved multipart laminated members is

Outline of Station Building
Hyugashi (Hyuga City), located in northern Miyazaki Prefecture, is the area’s forestry center. The area has a warm climate,but is also known as a passageway for typhoons.
Architectural and urban studies wereconducted with regard to the station building, the elevated railway and the townbuilding as well, in order to provide the visual transparency and lightweight
structural design that would be worthy ofsymbolizing Hyuga City and that would be
required for construction of the Hyugashi
station building. As a result, it was decided
that the structural plan for the station building shed would call for a fully-covered
wooden structure with a span of about 17.2

Platform

7,900

16,150Fig. 1 Section of Hyugashi Station Building

Skylight

17,200CanopyMain stationbuilding

Photo 1	Appearance of Hyugashi station building
11 Hyugashi Station Building

8,250

Skylight

11,350Canopym and a roof area of about 2,000 m2 thatwould cover the entire 110-m length of express trains (Fig. 1). Further, canopies wereplanned that would run the length of thestation building on either side, have large
depths of 7~11 m and be connected to theelevated railway. Structurally, the canopies
are supported by lightweight columns andare connected to the elevated railway in order to provide sufficient stability against
strong winds and the horizontal forces generated by earthquakes. The canopy structures consist of wooden roof framing that
extends outward on steel trusses and Hshape girders supported by two rows ofsteel pipe columns. The aesthetic arrangement of the canopies brings stability to thearchitectural configuration of the entire station building. (Refer to Photos 1 and 2)
Structural Types and Features
As the Hyugashi station building is a fullycovered station building having columns at
the outer edges of the elevated railway, it
imposes certain spatial restrictions, such assite border lines outside the building andrailway limiting lines inside the building.
In order to form a wood-steel composite
structure and secure the rigidity andstrength needed to resist strong winds andearthquakes under such restrictions, themajor task was to determine the kind of
structural system that should be adopted.
Diverse ideas were examined and, as aresult, it was decided to adopt a composite
frame with laminated members of Japanesecedar, a distinctive product of Miyazaki
Prefecture, arranged in the section above
the beams and supported from below by Hshape steel columns and steel tube diagonal
members. The interval between the laminated framing members is 3 m.

Photo 2 Inner view of platformJSSC
Fig. 3	Conceptual Drawing for the Method to Manufacture
Curved Laminated Members with Varied Sections

Fig. 2	Bending Moment of Beam Caused by Horizontal
Force

5.53
5.53

7.37
7.37

4.39
4.39

1.5 0
1.51

0.1
0.1

1.31
1.31
0

0
4.47
4.47
0

8.41
8.41
0.01

55

0

2.19
2.19

0.01

0.01

0.01

1) Manufacture of S-shaped curved laminated member

0.08
0.28

0
0

0.01
0

0
0.29
0.29

0

Cutting plane

0.29
0.29

0
00

0
0

Cutting plane
290

00

3.07
3.07

0

0

765

000

0.07
0.01
0.15
0.150
0.01 0.17
0.15
0.2

1005

0

0

240 765

0.11
0.11
0.16

3205

3205

5830

0.0125
0.05

00.25
0.05

9035

Horizontal force
0.03

0.03
0

0

2) Cutting to upper and lower sections using round saw
0.18
0.18

0.18
0.18
y
1.93 0.08
0

x

5.56

0.09
0

0.10

3) Additional laminar825

290 60300

cladding
the edges of
Cutting plane
Pressureboth the upperand lower parts
to clad the two
Pressure
parts.
Then,
Cutting plane(Cut extra member:the clad memUsed for the 1st-story column)
ber was cut at4) Formation of beam
18070
its narrowest
point.
4) The two cut
members wereBeam configuration conforming to the stressjoined on-sitewith soft curve line
at the cut-pointtocompletethe beam.
The members thus manufactured weretransported to the site, and assembled onsite with the arch members and struts (Photo 3). These assembled members were
hoisted and attached to the steel angle
brace framing (Photo 4). The entire framing of the station building shed was completed in this way.
Photo 3	Ground assembly of laminated mem350

The cylindrical roof is aesthetically located at the center of the wooden section.
In order to design such a roof, arch-shaped
members were required. For that purpose,
attempts were made to reduce the burden
placed on the horizontal beam members(bending members) at the span center byutilizing arches as thrusting resistance elements so that lightweight framing could beformed. The section below the horizontal
beam members was configured using Hshape steel columns (H-300 × 150 × 6.5 ×
9) and diagonal steel tube members (114.3
dia. × 6.0). The adopted structural plan has
the angle brace framing aligned across thespan and the brace structure aligned along
the ridgeline, with the laminated members
and the arches supported by the three-dimensionally configured diagonal steel tube
members.
Under vertical loads, there is no occurrence of large bending moments in any of
the structural members due to adoption of
the above-mentioned wooden arches andangle brace framing. However, horizontal
loads generated by earthquakes and windcause large bending moments in the wooden beams (Fig. 2). To solve this problem, it
is desirable for the beams to be configured
in a manner that is rationally resistant tobending moments.
In order to produce the curved multipart, laminated members thus required, theapproach shown in Fig. 3 was applied:1) First, the S-shaped members were manufactured using the commonly applied
method.
2) The members thus prepared were cut linearly so as to divide them into two equalparts.
3) The upper part was placed under the
lower part so that they would adhere toeach other; a linear laminar was added to

Rational Framing Capitalizing on
Composite Structures
Realization of the framing method mentioned above has led to the formation offraming that offers sufficient rigidity andstrength against not only vertical loads but
horizontal loads as well, in both the direction of the span and the direction of theridgeline.
Instead of certain spatial restrictions being imposed on the construction of a fully
covered station building shed, it was possible to successfully create framing capable of satisfying both architectural andstructural requirements using laminatedcedar members that are low in strength andrigidity. It can be said that success waslargely attributable to the application of awood-steel composite structure in a man-ber girder

Photo 4 Hoisting of laminated member

ner consistent with the principle: “rightmaterials for right places.”
Hyugashi Station Building 12

Structural Design of the Kochi Station Building
By Mamoru Kawaguchi
Emeritus Professor of Hosei University (Representative, KAWAGUCHI & ENGINEERS)
Kochi City is located in the center of Kochi
Prefecture and in the midst of a prospering
forestry industry. While the city benefits
from a warm climate, it is also known to lie
in the pathway of typhoons. Thus, in planning structural design, it is important to pay
ample consideration to the wind.
The basic design of the Kochi stationbuilding highlights a large vault-shaped
frame that spans the elevated tracks fromthe south side of the tracks to the upper section of the north-entrance canopy (a steelreinforced concrete composite rigid frame)that stands in the station plaza independently of the elevated railway. The structural design of the building was premisedon the use of Japanese cedar produced in
Kochi Prefecture.
Further, the south-entrance canopy is asteel structure with a great depth of 13.5 mthat is located on the south side of the elevated railway. The canopy was designed toconnect to the elevated railway, and because the elevated structure provides stability against horizontal forces caused byearthquakes and strong winds, the canopy
was designed to be supported with lightcolumns.

Fig. 1 Section of Kochi Station Building

Structural Outline
The roof of the Kochi station building has
a vault-shaped configuration with a span of
about 39 m and a length of about 60 m, anda maximum height of 23.4 m. The upper
chord members that constitute the vault are
installed at intervals of 4.5 m and rise fromthe north-entrance canopy. Because theconstruction work had to be conducted so
as not to suspend railway operations in thearea where the south-side canopy was to beplaced, a structural type was adopted
whereby the arch legs on the south side
would not extend to the ground but would
be affixed to the elevated structure supporting the tracks.
Meanwhile, in order to secure the required clearance for the trains, a dogleg
shape was adopted for the roof on the south
side of the elevated structure, giving theroof as a whole an arched asymmetricshape (Fig. 1 and Photo 1). The lower
chord members run between two upper

chord members and forks into
two branches near the end to joinwith the upper chord arch. However, on the south side of the elevated structure, the lower chordmembers connect to the upper
chord members near the foldpoint of the dogleg in order topreserve the required clearance
for the trains. To secure the horizontal resistance of the structurein the east-west direction below
this point, a system composed of
x-braces is provided to include Photo 2 Interior view of large roof
this level for the three bays near
the east and west ends of the structures, re- onal members are made of steel tubes.
spectively. (Refer to Photo 2)
The maximum depth of the arch is 2.8 Structural Systems and Featuresm, and the upper and lower chords are as- Wooden structures are generally less effisembled three-dimensionally using lattice cient at transferring tension and bending
members. The upper chord members are stresses at joints than they are at transfercomposed of laminated cedar, excluding ring compression stress. Accordingly, thethe dogleg, and the lower chords and diag- following approach was adopted. Namely,

13 Kochi Station Building

H-shape steel upper
chord member

Laminated wood upper
chord member

South-entrance
canopyNorth-entrance
canopyPhoto 1 Appearance of Kochi station building

JSSC
Fig. 2 Assembly and Detailed Drawings for North-side Column Leg

Sectional
view cSectional
view bKanzashi (hair stick) boltc
Stiffening platebaKanzashi (hair stick) bolt

Sectional
view aIn the station building, because threedimensionally assembled diagonal members serve as both roof in-plane braces andseismic-resistant braces, the horizontal
forces that are at work during wind loadingand earthquakes are smoothly transferredto the elevated railway structure in bothtransverse and longitudinal directions.
In order to smoothly transfer forces between the upper chord cedar members andthe steel members, special details were designed. While compression force occurs in
the north leg of the laminated member
arches during vertical loading, there arecases in which tension force can occur during earthquakes and wind loading, thereby
necessitating the safe transfer of this force
to the metal anchor fittings at the base of
the columns. In such cases, it is general inlaminated cedar members (150 × 900, in a
double-wall structure) were used for theupper chord members where compression
force is dominant; H-shapes (H-800 × 250
× 16 × 25; varied sections) were adopted tohandle the large bending stresses at workaround the dogleg on the south end of thearches; and steel tubes (190.7 in dia. × 23
for chord; 114.3 in dia. × 15 or 9 for diagonal member) were used for the lower
chords and diagonal members where tension force dominate.
In this way, a composite structure ofwood and steel was adopted in a mannerconsistent with the principle “right materials for right places” in which steel is pairedwith wood to cope with large amounts oftension and large bending moments against
which wood is not strong enough.

Photo 3 North-side column leg

conventional joining methods to insert asteel plate with multiple holes in the timber
members into which bolts, drift pins or other kinds of steel bars are inserted, allowing
the transfer of force between the wood andsteel members via the shear and bending of
the inserted steel bars.
In the Kochi station building, such a
conventional approach was rejected in favor of a new method whereby a thick steel
plate is inserted into a rectangular hole cut
into the bottom of each wooden member;the steel plate is then fastened with bolts toa metal anchor fitted to the outside of thewooden member (Fig. 2, Photo 3). Thisjoining method allows the wooden members to demonstrate reasonably large bearing force.
Joining of the laminated wood members
and the lattice members was conducted using detail fittings based on the same concept mentioned above. A protruding crossshaped member was weld-joined to thesteel plate where the lattice members areattached; notches conforming to the crossshaped protrusions were cut in advanceinto both sides of the laminated members;
and the protrusion was then sandwiched
between the two laminated members. The
steel plate was tension-joined to the laminated members using bolts in a manner
similar to that used for the north end of thelegs mentioned above. (See Fig. 3, Photo
4).

Fig. 3 Assembly and Detailed Drawings for Laminated Wood-Lattice Jointab

Sectional
view aSectional
view b

Photo 4 Laminated wood-lattice joint
Cross-shaped protruded
member
Kochi Station Building 14

Connection Design of Steel-Concrete
Hybrid Structures
By K
 oichi Minami, Prof., Faculty of Engineering, Fukuyama University
Toshiyuki Fukumoto, Building Structure Group, Kajima Technical Research InstituteKenji Nishiumi, Technical Development Bureau, Nippon Steel Corporation
Design Guidebook for Connectionsin Steel-Concrete Hybrid Structures
A hybrid structure is composed of different
materials or various structural members andsystems in a manner consistent with the principle: “right materials for right places.” Compared to conventional structural systems, a hybrid structure offers enhanced freedom instructural configuration vis-à-vis safety, productivity, economical advantages, architectural space and structural landscaping.
Because hybrid structures require the joining of diverse structural materials, members
and systems to complete the composite construction, many connecting methods havebeen proposed. However, neither a force transfer mechanism model nor a structural performance assessment method common to or fundamental for hybrid structures has been
established. Thus, verification of structuralsafety currently depends on experimentation.
To resolve this situation, the Japanese Society of Steel Construction has created a“Working Group on the Preparation of a “Design Guidebook for Connections in Hybrid
Structures” aimed at establishing a common or
fundamental method to assess the structural
performances (strength, deformation capacity,
force transfer, etc.) of connections used insteel-concrete hybrid structures in the fields ofbuilding construction and civil engineering.
As a first step, the Group organized the existing technologies and design specifications in
those fields and examined the shear connector
and structural performance assessment methods common to these two fields in order to findwhich of them could be applied to the connections of future hybrid structures.
Based on these organizational efforts andon examinations thus far completed, the Grouppublished the Design Guidebook for Connections in Steel-Concrete Hybrid Structures. It
consists of three parts: connections in hybrid
structures (shear connector, bond) common to
15 Connection Design of Steel-Concrete Hybrid Structures

both building construction and civil engineering; connections in hybrid structures used inbuilding construction; and connections in hybrid structures used in civil engineering. The
Guidebook is outlined below.
Part 1: Connections in Hybrid
Structures common to both
Building Construction and
Civil Engineering
Hybrid structures are defined and classifications are made. Hybrid structures are roughlyclassified into two types: composite andmixed. “Composite structure” is a generalterm for structures composed of composite
members, and “composite member” denotes amember in which two different materials, steel
and concrete, are integrated at the cross sectional level. On the other hand, “mixed structure” generally denotes structures in which different members are connected.
Next, taking longitudinal and transverse
connections to be connections similar to thoseused in building construction and civil engineering, a comparison was made of the connection design methods used in these two
fields. The force transfer mechanisms for longitudinal connections are classified into thosethat employ bearing and friction forces using
lever force and those that employ shear connectors. The former is generally adopted inbuilding construction, and the latter in civil engineering. The major reason for this difference
lies in the fact that the resistance mechanism
changes depending on the rigidity of the steel
members and the confined condition of the reinforced-concrete members. This means thatin building structures with comparatively
more heavy-wall sections and high confinedforce, the first mechanism is dominant, andthat in civil engineering structures with morethin-wall sections and low confined force, thelatter dominates.
On the other hand, force transfer mecha-

nisms in transverse connections are classified
into those that form concrete compressive strut
and bearing strength when the confined force
is sufficient and those that use shear connectors and shear-reinforcing steel members
when the confined force is insufficient. The
former is generally adopted in building structures, and the latter in civil engineering structures. However, when expanding the range ofapplications of both structures, it is effective to
adopt the mechanism that incorporates theneeded features in both fields.
In addition, a design method pertaining tobond (friction and shear connector) and bearing, the two force transfer elements at connections, is introduced and an arrangement of thisapproach to assess the load bearing of shear
connectors using numerical analysis is made.
Part 2: Connections in Hybrid
Structures in Building Construction
The contents of the design specification prepared by the Architectural Institute of Japan
were systematically organized to introduce experimental research results and a structural
performance assessment method as the latest
research achievements. The target connections
are for steel-reinforced concrete (SRC), composite steel tube and concrete, and concretefilled steel tube (CFT) composite structures;composite beams, hybrid beams; and mixed
structures composed of RC columns and steel
beams.
For SRC-structure connections, data on
beam-to-column connections (Fig. 1), columnbases, joints and bond for reinforcing bar andsteel were organized and examined. Composite steel tube and concrete structures (Fig. 2)
are generally classified into three types according to the type of column members used: thefilled type in which concrete is placed into thetube, the encased type in which reinforcedconcrete is wrapped around the exterior of theJSSC
Fig. 1	Beam-to-Column Connection of SRC
Structure

Fig. 2	Beam-to-Column Connectionof Composite Steel Tube andConcrete Structure3)

Fig. 3	Beam-to-Column
Connection of CFT
Structure

Steel tube

Beam Deck plate floor
Steel-frame
beam

Square CFTColumnConcrete filling hole

Column(cast-in-place SRC)(a) SRC column and SRC beam1)

Inner diaphragmplate(b) SRC column, SRC beam2)

Fig. 4	Beam-to-Column Connection of
RC Column-Steel Frame Beam
Mixed Structure4)

Fig. 5	Corrugated Steel Web
PC Bridge
Outer PC
cable

Fig. 6 Hybrid Rigid-frame Bridge
Steel girder

Corrugatedsteel web

Rigid joining

Upper
floor slab

Rigid joining
RC bridge pierLower floor slab
Inner PC cabletube, and the encased/filled type. The filled
type is known as CFT, and accordingly thebeam-to-column connections of the encasedand encased/filled types were taken up in the
Guideline. CFT structures are increasingly being adopted for high-rise buildings due to theirsuperior structural properties and economical
advantages. Data on beam-to-column connections (Fig. 3), column bases, joints and bondfor steel tube in CFT structures were organizedand examined.
For hybrid beams, the design of the force
transfer mechanism is introduced for the connections of composite beams in which steelframe beams and RC floors are integrated using a headed stud (shear connector) to form
T-shaped beams. The design of the force transfer mechanism is also introduced for the connections of long steel beams in which bothends of the beams are formed using RC structures (or SRC) and the center section retains its
steel-frame structure. Further, data regarding
the structural performance of and design method for beam-to-column connections in RC column-steel beam structures (Fig. 4)—mixed
structures using different material members ina manner corresponding to “right materials forright places”—were organized and examined.
Part 3: C onnections in Hybrid
Structures in Civil Engineering
Because the design specifications for composite girders and columns in the field of civil engineering have already been determined by theJapan Society of Civil Engineers and other related organizations, a method of assessing
structural performance based on recent research and actual applications of the connections in new hybrid structures that are seeing
growing use is introduced. The target structures include composite section girders,mixed-structure bridges, hybrid rigid-frame
bridges and hybrid foundations.
As regards composite section girders, two
examples are cited: a PC composite steel truss
bridge and a corrugated steel web PC bridge(Fig. 5), in which PC slabs are adopted for theupper and lower floors and steel truss members or corrugated steel plates are used for theweb. The mixed-structure bridge targets
bridge structures such as mixed cable-stayed
bridges, mixed extradosed bridges and mixedgirder bridges, in which steel girders and concrete girders are connected in the bridge longitudinal direction. The hybrid rigid-frame
bridges (Fig. 6) targets mixed structures inwhich steel girders and RC piers are rigidly
joined. The hybrid foundations covers mixed
foundation structures in which steel columns(composite columns) and RC pile foundations
are connected. The types of connections inthese targeted bridges were classified and thedesign method for each connection type is introduced.

and guidelines pertaining to the connections
used in hybrid structures, the results of whichwere incorporated in the Design Guidebook
for Connections in Steel-Concrete Hybrid
Structures. In the Guidebook, design guidelines have not yet been determined for the
structural design of every connection of every
hybrid structure that will be developed in the
future. However, it is considered that a comprehensive framework for connection design
has been proposed in the Guideline throughthe organization and systematization of current guidelines and the sampling of futuretasks.
In the future development of new connections for use in hybrid structures, it will be vitalthat structural design guidelines be developedthat can assess the structural performance of
these new connections without testing.
Source of figures
1) Architectural Institute of Japan: Teaching
Material for Structures, Revised 2nd Version,
Feb. 25, 1995
2) Concrete Engineering, Vol. 21 No. 12 “Special Feature: Concrete and Composite Structures, Design Examples (1),” December 1983
3) Architectural Institute of Japan: Teaching
Material for Structures, Revised 2nd Version,
Feb. 25, 1995
4) Concrete Engineering, Vol. 33 No. 1 “Combination of RC Members and S Members,”
January 1995

The Guideline: Comprehensive
Framework for Connection Design
The Working Group organized and examinedexisting technologies, design specifications
Connection Design of Steel-Concrete Hybrid Structures 16

International Events and Symposium
Anton Tedesko Medal Awarded to JSSC President Takanashi
The Anton Tedesko* Medal is an important
award given by the IABSE (International
Association for Bridge and Structural Engineering) Foundation in recognition ofachievements in structural engineering.
The award has two categories: notable contributions to the development of structural
engineering and organization of a study
leave abroad for a young promising engineer outside his/her home country withprestigious engineering firms. Dr. Koichi
Takanashi, President of the Japanese Society of Steel Construction, was presented
this prestigious medal in recognition of his“notable contribution to structural engineering and his efforts to nurture many
young researchers in that field.”
Dr. Takanashi mentored students at the
University of Tokyo and Chiba University
who have attained great achievements of
their own. His major fields of research
fields are plastic design and seismic design.
Many graduates who attended Dr.
Takanashi’s lectures play active roles inmany regions of the world, and their re-search has contributed greatly to the sounddevelopment of steel structures the world
over.
Dr. Takanashi’s contributions to thefield of structural engineering are diverse.
He served as chairman of the Structural
Committee of the Architectural Institute ofJapan for four years and as chairman of theCommittee to Evaluate High-rise Buildings of the Building Center of Japan foreight years and, further, was the guiding
hand in organizing and establishing the national qualification system for earning thelicense: First Class Structural Design Architect. Recently, he was extensively involved in promoting a collaborative project
between government agencies known as
New Structural Systems Employing Innovative Structural Materials (for details, refer to issue No. 28 of Steel Construction
Today & Tomorrow). His achievements
were introduced in IABSE reports.
Further, Dr. Takanashi has contributed
greatly to the development of IABSE, including the presentation of papers at sym-

posiums and congresses sponsored by
IABSE and the delivery of keynote addresses and invitational lectures at thosemeetings. He served as vice president of
IABSE from 1997 to 2005 and participatedin many IABSE committee operations.
*Structural designer: Though born in Germany, he is active in the US and is called
the father of the thin-wall concrete shell.

Dr. Takanashi receives medal from Mr. Klaus
Ostenfeld, Chair of IABSE Foundation Council

The 9th Pacific Structural Steel Conference
The Pacific Structural Steel Conference ed. The keynote addresses and paper pre(PSSC) is an international conference on sentations covered a wide range of themes
steel structures, held by 10 nations: U.S.A., pertaining to bridges and buildings: design,
Australia, Canada, China, Chile, Japan, construction, fabrication, materials, mainKorea, Mexico, New Zealand and Singa- tenance and new technologies. During thepore. Since the first conference was con- conference, advanced technical informavened in 1986, it has been held
once every three years.
The latest conference was theninth of the series and was held
in Beijing, China, for three days
from October 20, 2010 under the
auspices of the China Steel Construction Society. Although
Chile and Mexico did not participate in the conference, the U.K.,
South Africa and Hong Kong did
take part. The total number ofparticipants exceeded 600, and a
total of 266 papers were presentConference scenes
17 International Eventstion regarding the respective nations was
exchanged.
Prior to the conference, the PacificCouncil of the Structural Steel Association(PCSSA) met and decided to hold the next
PSSC in Singapore in 2013.

JSSC

JSSC Symposium 2010 on Structural Steel Construction
The Japanese Society of Steel Construction(JSSC) held the JSSC Symposium 2010 on
Structural Steel Construction on the 18thand 19th of November 2010, with the cooperation of its membership, JSSC’s various committees and related organizations.
In the panel session, the winners of the
JSSC President Prize and Thesis Prize
were introduced. With the total number ofparticipants exceeding 500, the symposium served as a venue for exchanges between researchers and engineers involvedin steel construction and for the collectionof information. The major events are outlined below.

rosive environments, in environments
where maintenance is difficult and in otherdiverse environments. This has lead to thegrowing use of stainless steel in a wide
range of social infrastructure construction.
In the session titled “The Increasing
Role of Stainless Steel,” the definition, features and diversity of applications for stainless steel were introduced from the aspectof the material. Further, examples of thepractical application of stainless steel inenergy-related facilities, stainless steel reinforcing bars, exterior decorative building
members, and civil engineering/building
structures were introduced.

Engineering Session: High-strength
Bolt Joining Technologies
The objectives for establishing the Working Group on High-strength Bolt Joining
and for the group’s operations were introduced. Among the topics introduced at thesession were the historical development ofhigh-strength bolt joining technologies andtheir application in the US and the development of high-strength
November 18, 2010bolt joining in Japan in
Stainless Steel and Academy Sessions
reference to the US. In
Engineering Session
International Committee Meeting
Friendship Party
Lecturesaddition, recent technological topics were
Panel Exhibition: JSSC
Stainless Steel:
President Prize-winning
Increasing Role
Fatigue
discussed―ultrahighPerformancesin Construction(civil engineering)
Structural Framing
strength bolts; higher(building construction)
slip factors; stress
Board ofDirectors' Meetingtransfer in front of bolt
holes; local tearing
Bridges
Technology/(civil engineering)Awarding ofStandardization
fracture strength asJSSC Prizes
Committee Meeting
Design, Composite
Awarding
Ceremony
sessment;
highStructures
Prize Winners’(building construction)
strength bolt joining
International
LecturesCommittee Meetingand tension introduction; assessment of theSpecial Lectures
relation between frictional resistance/fricFriendship Partytion surface treatment
and the friction coeffiNovember 19, 2010
cient; and a highVibration, Vibration
strength bolt joining
Structural Members
Control
Repair, Reinforcing(building construction) (building construction)(civil engineering)
method (strength rating method).

Session: The Increasing Role ofStainless SteelLong-term durability is being cited as oneof the excellent environmental performance characteristics essential for social
infrastructure. Stainless steel, due to its
high corrosion resistance, is attracting attention as a structural material that can remain sound when applied in severely cor-

Materials, Joining (1)(building construction)

Vibration, Seismic
Resistance(civil engineering)

Structural Analysis
Materials, Joining (2)(building construction) (building construction
and civil engineering)

Maintenance (1)(civil engineering)

Maintenance (2)(civil engineering)

Academy Session
JSSC has annually published the Journal of
the Japanese Society of Steel Construction
since 1993. In conjunction with the publication, a lecture meeting is held as an academy session, which is used as a venue forthe presentation of papers and the exchange
of information among researchers, engineers and students involved in steel construction.
The current session was the 18th in theseries and included the lecture meeting for2010 and the presentation of the Thesis
Prize.
Special Lecture: Success in Vibration Collapse Tests for Full-scale
Steel-structure BuildingThis presentation described a full-scale
4-story building collapse that was conducted at the D-Defense as the subject of acomplete collapse test, the procedures for
examining excitation and measurement
methods at the preparation stage and thedecisions made on the test date that led to
the world’s first successful test in which afull-scale building was collapsed by meansof shaking tables. Specifically, “experimental knowhow” that could not be readfrom the written report was explained. In
this regard, Associate Professor Tetsu Yamada of the Tokyo Institute of Technology
delivered a lecture on reference information in challenging new tests for steel construction in addition to the above test.
Greeting by
JSSC President
Koichi Takanashi

 Special lecture meeting

PSSC 2010
For details, refer to the“9th Pacific Structural
Steel Conference” onthe previous page.
Friendship party
JSSC Symposium 18

To Our ReadersStarting with issue No. 26 of Steel Construction Today &Tomorrow, the International Committee of the JapaneseSociety of Steel Construction (JSSC) assumed responsibility
for the editorial planning of one of the journal’s thriceannual issues. Since its inauguration, JSSC has promoted
surveys, research and technological development supporting the expanded use of steel construction and to improve steel construction technologies. At the same time,
JSSC regularly extends cooperation to related international organizations.
Following with the merger of JSSC with the StainlessSteel Building Association of Japan in April 2010, JSSC’s
fields of operation now include not only carbon steel but
also highly corrosion-resistant stainless steel. ConsequentMasatsugu Nagai
ly, we intend to actively transmit information throughout
Chairman, International
Committee of JSSC
the world related to a wider range of steel construction(Prof., Nagaoka Univerareas.
sity of Technology)
As was true in issue No. 29, the current issue, No. 32,
leads with the announcement of the JSSC President Prize
and Thesis Prize winners. Other major topics in this issue
include the design of composite structure joints; awarding of the Anton Tedesko Medal to
JSSC President Koichi Takanashi and the Pacific Structural Steel Conference for 2010, an international conference attended by ten Pacific region nations; and JSSC Symposium 2010
on Structural Steel Construction, an annual event held with support from the JSSC membership and related committees and organizations.
In addition, there is a special feature on railway facilities built with steel composite
members. Given the active promotion of infrastructure improvement/development inemerging nations, this feature introduces steel-concrete composite railway bridges andsteel-wood composite station buildings that have recently been completed in Japan.
The International Committee, while working on multiple responses to the internationalization of steel construction codes, promotes exchanges of technical information and personnel with overseas organizations. As a link in these operations, we hope that this annual
issue will inform our readers of JSSC operations, trends in steel construction, and the technologies and technological development involved in planning, designing, and building
steel structures in Japan.
If you wish to obtain more detailed information about the various articles that are contained in this issue or to receive related technical information, please do not hesitate tocontact JSSC staff member Hiroshi Sugitani (h.sugitani@jssc.or.jp).
JSSC President Prize-winning works
Core wallload-transfer frame Core wall andload-transfer
frame for new
jack-down building demolition
method

1
2
3
4
5
5
6
6
7
11
13
15
17
17
18

New Jack-down Demolition Method forHigh-rise Buildings
Flat Plate Supported by Steel Bar Columns
and Steel Capitals
BHS: High Performance Steel for Bridges
D-Runway at Tokyo International Airport
Flexural Shear Behaviors of Short-span
Beam with Preceded Shear Yielding
Retrofit Measure of Weld by Semi-circular
Notch in Orthotropic Steel Deck
Seismic Uplift in Single-story Structureswith Single Axis Asymmetry
Evaluation of Behavior of Fatigue Crack by
XFEM Analysis
Steel-Concrete Composite Bridges
Hyugashi Station Building
Kochi Station Building
Connection Design of Hybrid Structures
Awarding of Anton Tedesco Medal
9th Pacific Structural Steel Conference
JSSC Symposium

COVER
Four selections of JSSC President Prizes for 2010:(upper left) Jack-down high-rise building demolition method (for details, see page 1); (upper
right) Strong Building employing flat plate supported by steel bar columns and steel capitals(page 2); (lower left) Bridge high-performancesteel (BHS) used for Tokyo Gate Bridge (page 3);(lower right) New D-Runway at Tokyo International Airport (page 4)
A magazine published jointly by
The Japan Iron and Steel Federation
3-2-10, Nihonbashi Kayabacho, Chuo-ku, Tokyo
103-0025, Japan
Phone: 81-3-3669-4815 Fax: 81-3-3667-0245
Chairman: Eiji Hayashida
URL http://www.jisf.or.jp
Japanese Society of Steel Construction
Yotsuya Mitsubishi Bldg. 9th Fl., 3-2-1 Yotsuya,
Shinjuku-ku, Tokyo 160-0004, Japan
Phone: 81-3-5919-1535 Fax: 81-3-5919-1536
President: Koichi Takanashi
URL http://www.jssc.or.jp
Editorial GroupJISF/JSSC Joint Editing Group for Steel Construction Today & Tomorrow
Editor-in-Chief: Tetsuya Akahoshi
The Japan Iron and Steel Federation● Beijing Office
Room 2206, Jingtai Tower, 24 JianguomenwaiStreet, Chaoyang-District, Beijing 100022, China
Phone: +86-10-6515-6678
Phone: +86-10-6515-6694

Strong Building
employing flat plate

Artist’s sketch of Tokyo Gate Bridge

Special Issue
Japanese Society of Steel Construction

Steel pier section for New D-Runway
at Tokyo International Airport

STEEL CONSTRUCTION TODAY & TOMORROW ispublished three times per year to promote better
understanding of steel products and their application in construction field and circulated to interested executives and companies in all branches of trade, industry and business. No part of thispublication can be reproduced in any form without permission. We welcome your comments
about the publication. Please address to Lettersto the Editor.