No. 35
March

2012

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

Special Issue

Japanese Society of Steel Construction

http://www.jisf.or.jp/en/index.html

JSSC President Prizes 2011
Hoki Museum
Prize winners: Nikken Sekkei Ltd. and Obayashi Corporation
A notable structural feature of the Hoki Museum is the 100 m-long box-shaped steel
plate structure that constitutes one section of
the museum. Supported at two points so thatit floats above the lower structure, the boxshaped section is cantilevered for 30 m at oneend (Photo 1). This structural system expresses the architectural concept of “floating in theforest.”Jutting outward in one direction, the boxshaped girder has a cross-sectional configuration consisting of two walls, and two floors (afloor and a roof). The outer wall of the box
beam has a gentle arc shape (Photos 2 and 3),
the undulation of which is overlapped by the
inner wall that serves as an exhibition wall.
Since the overlapped section houses thestairs, adequate overlap was provided in thefront and rear of the stairs. Therefore, resis-

tance is provided by the inner and outer walls.
The two horizontal surfaces (floor androof) and the two walls of the box-shaped
girder comprise a double-walled steel plate
structure containing steel shapes (H250) andlight-gauge steel channels (C250). Coatedsteel plates were used as-is to provide a finished surface for the exterior walls, exhibition walls and ceilings. Many small holes areadded in the ceiling plate and used for LED
lighting and air-conditioning vents. Wiringand ducts run through the double-walled steel
plate structures. Paintings are hung on thesteel-plate exhibition wall using magnets.
(Photos 4 and 5) The steel plate itself defines
the structure, the design and the function—aswell as the architecture.
The structural properties of the doublewalled steel plate structure were confirmedby means of plug welding, stiffening effectand cyclic shear tests. In addition, the actual
performance characteristics of the completed
cantilevered structure were verified by meansof loading tests. Because this museum is anarchitecturally unusual structure, three-dimensional building information was shared
among the related parties during member
manufacture and installation. Advanced technologies were extensively utilized to secure
the highest accuracy in on-site welding,straightening and installation. On top of this,we strongly feel that this project enabled therelated parties to share interests and capabilities inherent in monodzukuri, or building
construction. The Hoki Museum is a steelstructured building with a scale, weight limitations and functions that only steel products
can provide.

Photo 2 Cantilever structure

Photo 1 Full view of box-shaped steel-plate structure

Photo 3 On-site construction

Photo 4	Inner view of box-shaped steel-plate
structure
1 Steel Construction Today & Tomorrow March 2012

Photo 5	Construction of box-shaped steel-plate
structureJSSC President Prizes

Nagoya City Science Museum
Prize winner: Nikken Sekkei Ltd. and Takenaka Corporation
A notable feature of the Nagoya City Science Museum is the spherical structurewith an outside diameter of about 40 m thathouses a world-class planetarium. The
spherical structure is sandwiched between
the east- and west-side buildings having anearly regular rectangular plane configuration. Since the spherical structure is notsupported by pillars, it looks as if it floats(Photo 1).
The spherical structure is composed ofupper and lower hemispheres, taking into
account their respective construction processes. The upper hemisphere constitutes
the dome of the planetarium, and in orderfor the whole sphere to float, the lower
hemisphere is designed to support thespherical structure’s great weight of about
40,000 kN. (Refer to Fig. 1 and Photo 2)
In constructing the lower hemisphere,

an arch frame to carry the vertical load was
installed in the X-shaped plane position
that connects support columns in the eastand west-side buildings and the core of thesphere (Fig. 2). The structure’s rigidity is
obtained by installing a truss frame in theouter shell and on the floor of the sphericalstructure.
In the construction of the upper hemisphere, a composite truss structure composed of system trusses and steel tubes was
adopted to mitigate the burden placed on
the lower hemisphere, thereby reducing theweight of the entire spherical structure.
A single-span rigid-frame system, approximately 20 m in length in the lateral
direction, was adopted to effectively utilizebuilding space. Because the horizontal rigidity of a single-span rigid frame is low,
the necessary rigidity and strength were se-cured by filling the steel tube columns withconcrete and applying steel-frame braces
and viscous dampers.
The construction plans called for thebuildings on the east and west sides to bebuilt first, followed by the spherical structure. In the construction of the sphericalstructure, the lower hemisphere was temporarily supported by 31 bent columns, andafter completion of the steel-frame workfor the lower hemisphere, it was lowered
into the prescribed position using jacks.
The spherical structure employs closed
framing, and thus high dimensional accuracy is required for both the manufacture
and installation of the frame. To attain this,various approaches were applied to secure
structural precision—an elaborate temporary assembly process, precision control of
the installation, and stress measurements.

Fig. 1 Section of Nagoya City Science Museum
Yield strength 385 N/mm2 steel
Concrete-filled steel
columnYield strength 440 N/mm2 steel
Bucking-restrainedbrace

Dampingbrace

Cast steel
Upper hemispherecomposite truss
structure

39 m
Lower
hemispheretruss structure
10.6 mFoundation :spread foundation

38 m in diameter of steel structure

Fig. 2 Structure of Lower Hemisphere
Main frame

Support column

A

Photo 1 Spherical structure to house a planetarium
About 20 m

A
About 35 m
V59

Compression member

Tension member
A-A section

Photo 2 Full view of Nagoya City Science Museum
March 2012 Steel Construction Today & Tomorrow 2

Large-roof Sliding Method for Airport Building
Prize winner: Kajima Corporation
A large roof was installed over the check-in
lobby of the international passenger terminal that opened in October, 2010, at Tokyo
International (Haneda) Airport. The roof
has a bow-shaped cross section that recalls
the lower slope of Mt. Fuji.
The large roof is a long-span steel-frame
space truss structure (69 × 162 m) composed of ten connected space truss frames
sitting on columns spaced 69 m apart. A
sliding method was used for constructionof 16,000 m2 out of 18,000 m2 of total roof
expanse. Excluded were one span on thenorthern tip and a part of railway accesssection.
In the sliding method, each integrated
space truss frame (9 × 92 m) was slid 18 m
on temporary rail beams placed on column
heads via a sliding jack provided on theheads of the truss-support columns; theframe was then connected with anotherspace truss frame. Because the final slide

involved 9 rows of connected space truss building construction. This achievement
frames weighing about 5,000 tons, the roof shows new potential in the construction of
was slid using two PC wire strands (28.6 large-span steel structures. It is expecteddia.) set on each column head and two 50- that the new know-how obtained in the curton center hole jacks. The jacks moved the rent project will be put to practical use in aheavy roof by use of the stroke of the jacks diverse array of construction sites.
with the reaction set
Photo: © Ishiguro Photographic Instituteahead of 2 spans(L=36 m). The stroke
position and loading
condition of eachjack were automatiTemporarily installed rail beam(column head position)
cally controlled employing a built-in
CPU control box.
The huge roof
was fortunately completed on schedule
thanks to successfullarge-scale sliding
Third floor (check-in lobby floor)
work that had never Photo 2 Fifth sliding
before been used in Sliding from the rear (north side) to the front (south side) in 6~8 hours

Photo: SS Tokyo: Hisaaki Suehiro

Photo: © Ishiguro Photographic InstituteSliding direction

Photo 1	Full view of large roof of international passenger terminal building

Photo 3 Seventh sliding
Under construction of metallic roof in 5 spans; installation of 5-row skylights

Fig. 1 Section of International Passenger Terminal Building
Railway access section(post construction)

Sliding range (about 100 m): Sliding rail beam (column head position)

MonorailColumn-to-column span (69 m)

Keihin expressway train tunnel
3 Steel Construction Today & Tomorrow March 2012

JSSC President Prizes

Using Steel to Restore the Attractiveness of RC Structures
Prize winner: Takenaka Corporation
The building construction market is surrounded by many emerging issues—the reduction of new building markets due to a
declining population and a maturing society and the need to respond to a low-carbon
society, enhanced disaster prevention requirements and seismic reinforcement efforts. Given this situation, it is necessary toensure that existing buildings are transferred to the next generation as sound-quality social stock. In promoting the seismic
retrofitting of existing buildings, it is now
required that not only seismic resistance be
improved but that added values such as restored attractiveness be improved as well.
In conventional seismic reinforcement,
because the RC walls or steel-frame braces
are installed on a building’s exterior or interior, seismic reinforcement often imposes restrictions on building use during reinforcement work or after the reinforcement
work is complete. Reinforcement from abuilding’s exterior (outer shell reinforce-ment) is the most suitable method for securing the building’s interior functions,making possible continuous use and theability to respond to future needs.
To these ends, diverse retrofitting ideas
have been put into practical use that meetthe need for improved appearance of design, environmental sensitivity, or a shorter
construction term. These efforts have been
made possible by capitalizing on the positive attributes of lightness of weight, rigidity and strength peculiar to steel materials
and, further, by exploiting the slenderness,lightness, and prefabrication potential ofstructural members made of steel materials. Three recent examples are introduced
below.
● Example 1: A hospital building was converted to a welfare promotion center. The
RC wall inside the building was removed,
and a double-frame structure was designed
and installed on the building façade as alatticed steel frame so as to produce com-

Example 1 Conversion by Use of Latticed Double Frame

pound values: harmony with the surroundings, equipment concentration, higher ceilings, enhanced greening, and the effect ofeaves.
● Example 2: An existing 4-story RC
school building was retrofitted to an attractive 8-story building. A new framing method was applied that added 3 floors above
the rooftop and provided a base-isolation
system in the intermediate floor so as to retrofit the old school building as a symbol ofboth school and local community.
● Example 3: An existing RC department
store building was seismically reinforced.
By using triangular precast walls familiar
to local citizens to produce the desired appearance, the building was vigorously retrofitted capitalizing on the use of a triangular steel frame. This is an excellent example
in which higher strength is achieved and an
aesthetically refined building is restored by
the effective use of steel’s strength.

Plan and section after conversion

After conversion

Removal of seismic-resistantwall inside the existing building

Space for water-related
equipment

Before conversion

Concentration of seismic-resistant Seismic-resistant wall-free, flexible
Double-frame reinforcement with considerations
elements into latticed double frame working space with high ceiling height to the surrounding environment

Example 2 Vertical Enlargement Method to Utilize Intermediate
Base-isolation Floor
After retrofitting

Conceptual drawing of new framing method(STEP 0)

(STEPS 1~3)

(STEP 4)

2

1

Before retrofitting

Existing RC structure(no enlargement design)

Example 3 Restoration of Attractiveness of RC-structure Building
by Use of Triangular Steel Frame

1

1: Reinforcement of RC column andbeam by use of exterior-type frame
2: Installation of base-isolation device
3: Installation of long-span steel beam

Plan of reinforcement range

Load

2: Base isolation

Load

3: Long-span steel beam

4: Enlargement by use ofsteel structures

Connection of triangular steel frameand existing section
Connection

After restorationTop-endbracketBefore restoration

Shop
Existing
precastconcretewall (Pca)
Triangular steel frame

Triangularsteel frame

Triangularsteel frame

Existing
structure
InnerbracketMarch 2012 Steel Construction Today & Tomorrow 4

Thesis Prizes 2011
Experimental Research on the Mechanical Behaviors of Multi-row High-strength Bolted Friction Joints withThick PlatesPrize winner: Takashi Yamaguchi, Professor of Osaka City University and three other members
Takashi
Yamaguchi

1996: F inished doctoral
course, Graduate
School of Engineering,
Kyoto University
1996: A ssistant to Professor,
Graduate School ofEngineering, Kyoto
University
2009: P rofessor, Graduate
School of Engineering,Osaka City University

In steel bridge construction, there are increasing applications of heavy steel plate with thicknesses surpassing 75 mm
as a way to create rational structures, although this idea has never been put into practice. In the research on the use ofhigh-strength bolted friction joints in these heavy plates, tests to determine slip factor were conducted setting the number of bolt rows and the slip-to-yield strength ratio β as parameters. Supposing a joint with 75 mm-thick plate using
M24 high-strength bolts, a reduction model of 50 mm-thick plate using M16 high-strength bolts was prepared as atest specimen (Photo 1).
  The following were confirmed in the tests: In joints with four rows of bolts, simultaneous slip through the entire
joint occurred. Contrary to this, in joints with 12 rows of bolts, this kind of slip did not occur; rather, it first beganoutside the joint and then inside. Accordingly, as shown in Fig. 1(a), as the number of rows increases, the slip factor
decreases. In joints with a larger β where joint yielding occurs first, the reduction of axial force in the outside bolts islarge, and the reduction of the slip factor due to the increase in rows becomes large. Further, as shown in Figs. 1(b)and (c), in noting the reduction of bolt axial force at the moment slip occurs, it was learned that major slip occurs when
the axial force reduction rate of the center bolt, whose axial force is the last to decrease, surpasses about 8%.
Fig. 1 Test Results

Photo 1
Overview ofthe specimen(a) Relation between number of bolt rows
and reduction of slip factor(b) Change in axial force of M1612-0.72(c) Change in axial force of M16-121.3

Effects of Welding Conditions on the Charpy Absorbed Energy of Low-toughness Steel HAZ
Prize winner: Yoshihiro Sakino, Assistant Professor, Osaka University
Yoshihiro
SakinoAssistant Professor, Joining
and Welding ResearchInstitute, Osaka University

You-Chul KIM

Professor, Joining and
Welding Research Institute,
Osaka University

In the research targeting steel with extremely low toughness, the heat affected zone (HAZ) was simulated by meansof a synthetic heat-affected zone test as a uniform microstructure with unchanged material properties, which was subjected to the Charpy impact test. The heat cycle during multi-layer welding in the test was found using three-dimensional unsteady-heat-conduction analysis. Based on this, an examination was made of the welding conditions underwhich the Charpy absorbed energy of low-toughness steel increases.
  As a result of this examination, in the case of single-run welding of low-toughness steel as applied in the research,
the Charpy absorbed energy increased in FGHAZ and ICHAZ, but remained low in CGHAZ. However, when lowtoughness steel is subjected to a heat cycle in which the temperature reaches 880°C after the maximum temperaturein the bond line reaches1,350°C in multi-layer welding, the Charpy absorbed energy of the low-toughness steel increased greatly to 70J or more (at 0°C).
  As seen above, the research made clear that not only are there cases in which welding lowers the Charpy absorbed
energy of steel products but that there is also the possibility that the Charpy absorbed energy of low-toughness steel
can be increased by means of weld heat input control and postheating treatment.
Fig. 2 Effects of the Temperature after It Reaches the Maximum Level

Fig. 1	Charpy Transition Curve of
Low-toughness Steel Applied(a) Simulated welding heat cycle

5 Steel Construction Today & Tomorrow March 2012(b) Relation between maximum temperature in final run andCharpy absorbed energy

Thesis Prizes 2011

Study on the Static Characteristics of Web Connected Part of WBFW-type Beam-end Connection
Prize winner: Yugo Sato, Nippon Steel & Sumikin Metal Products Co., Ltd.
Yugo Sato2005: G raduated from Facultyof Architecture, Utsunomiya University
2007: G raduated from
Graduate School ofEngineering, Utsunomiya University
2007: E
 ntered Nippon Steel &Sumikin Metal Products
Co., Ltd.

When using beam-end connection in steel building construction, the WBFW (web-bolted, flange-welded)-type beamend connection method is adopted, i.e. beam webs are joined using high-strength bolts and beam flanges are joinedusing on-site welding. Up to now, the dynamic properties of beam-web high-strength bolt friction joints had not yet
been clarified. The study has targeted: to understand the dynamic properties of beam-web high-strength bolt joints in
WBFW-type beam-end connection and to accumulate the basic data required for assessing the dynamic properties of
WBFW-type beam-end connection. For this purpose, elasto-plastic finite element analysis was used with the column
width-to-thickness ratio and the arrangement of the high-strength bolts as parameters.
  It was obtained from the analytical results that, when the column width-to-thickness ratio is low and as the numberof bolts used increases, the bending moment to be borne by the beam-web joint tends to rise. Further, it is known thatthe column width-to-thickness ratio and the arrangement of the bolts affect the dynamic properties of beam-web highstrength bolt joints. Noting the time when sliding occurs and maximum yield strength is reached, the stress distribution of the various high-strength bolts was compared to examine the differences in stress distribution due to the column width-to-thickness ratio and the bolt arrangement.

Fig. 1	B62-Dt22: Stress Distribution of Beam-web
High-strength Bolt Jointat the Time of Sliding
Occurrence

Fig. 2	B62-Dt22: Stress Distribution of Beam-web
High-strength Bolt Jointat the Time of Maximum
Yield Strength

Fig. 3	Stress Condition of Beam-web Highstrength Bolt Joint Assumed in the
Current Design Method

Bolt group to bearbending moment
Bolt group to bear
shear force

Shear force Q

Bending
moment M

Bolt group to bearbending moment

Effects of Various Parameters on the Collapse Mechanism of Panels with Offset Beam-to-Column Connections of Steel Structures
Prize winner: Susumu Kuwahara, Associate Professor, Osaka University
SusumuKuwahara

1990: G raduated from Courseof Architectural Engineering, Osaka University
1992: Assistant Professor,
Course of ArchitecturalEngineering, Osaka
University
2005: Associate Professor,
Architecture and
Design, Kyoto Instituteof Technology
2008: Associate Professor,
Division of Global
Architecture, Osaka
University

In general, standard beam-to-column connection panels are commonly adopted in which both the right and left beams
connected to a column share identical beam depth and flange position. However, due to functional requirements andwith the aim of reducing the weight of the steel frame, connections were adopted in which the beams on either sideof the columns have a different beam depth and flange position (Fig. 1). Such panels are called uneven (offset) panels.
As shown in Fig. 2, these panels exhibit several collapse mechanisms.
  In this paper, an equation is proposed that calculates yield strength during the formation of various collapse mechanisms based on the elastic analytical method, and at the same time an examination using parametric calculations ismade of the effect of various parameters on panel yield strength. The research results thus obtained have clarified thecollapse mechanisms to be examined at the design stage depending on the sectional configuration of the columns andpanels.
Fig. 1 Offset Panel

Fig. 2 Various Collapse Mechanisms of Offset Panels

March 2012 Steel Construction Today & Tomorrow 6

Great East Japan Earthquake— Damages to Bridges, Port Facilities and Buildings, andTheir Restoration and Reconstruction —By M
 asatsugu Nagai
Chairman, International Committee, Japanese Society of Steel Construction

Fig. 1 Drawing of Epicenters (Map)

7 Steel Construction Today & Tomorrow March 2012

Fig. 2	Comparison of Spectral Acceleration Responses(Source: Hirose, East Nippon
Expressway Company Limited)
Design seismic motion level 2 (Type I)
II Soil Seed
Design seismic motion level 2 (Type II)
II Soil Seed
Great East Japan Earthquake
K-NET MYG004 Tsukidate (NS)Great East Japan Earthquake
K-NET MYG0013 Sendai (NS)Great East Japan Earthquake
IC observed wave Sendai-Higashi (NS)Great East Japan Earthquake
IC observed wave Shirakawa (NS)100000

10000
Spectral acceleration response (gal)At 14:46 on March 11, 2011, the Great East
Japan Earthquake (magnitude: 9.0) occurred,
unleashing seismic movement and tsunamisthat caused immense damage. The Japanese
Government has named this quake the EastJapan Great Earthquake Disaster (Great East
Japan Earthquake), or the 2011 Off the Pacific
Coast of Tohoku Earthquake (Japan Meteorological Agency). According to data collected
as of March 11, 2012, a total of 15,854 lives
were lost, with 3,155 persons still missing. In
the current earthquake, the damage caused by
the tsunamis was more serious than damage
resulting from seismic motions.
The earthquake was of the ocean plate typewith a seismic intensity of 7 (the maximum
value on the seismic intensity scale of the Japan Meteorological Agency) and a recorded
magnitude of 9, the largest ever observed inJapan. The hypocenter was located 130 km off
the coast of Tohoku at a depth of 24 km. The
fault zones covered a wide area (extending 500
km from north to south and 200 km from east
to west off the Pacific coast from the Sanriku
area to Ibaragi Prefecture) and caused three disastrous events in succession (Fig. 1).
The maximum acceleration observed was
2,933 gal (at Kurihara, Miyagi Prefecture),
and large accelerations of 2,000 gal or more
were observed at 19 other observation sites.

1000

100

10
0.01

0.1

1

10

Natural period (s)Fig. 2 shows the spectral acceleration responseof the current earthquake. While the seismic
motion was comparatively large, structuressuffered relatively little seismic damage. A
major reason for this was the current earthquake was dominated by spectral acceleration
with a short natural period of 0.3~0.5 seconds,
compared to the natural period that commonly
dominates buildings and public facilities. Another reason for less structural damage was theimplementation of seismic reinforcements
against great earthquakes that was carried out
following the Great Hanshin Earthquake(1995). Among other features of the current
quake were an extended vibration time andlong-period seismic motion components exceeding 20 seconds.
The most notable feature of the Great East
Japan Earthquake was the serious damage
caused by tsunamis. Waves with a maximum
height of 16 m not only brought about destructive damage to structures. It is reported thatdeath by drowning accounted for 95% of all
fatalities. Further it is reported that the maximum run-up height of the tsunami waves was
about 39 m. Photo 1 shows examples of tsunami damage, and Photo 2 offers an example

of ground liquefaction that occurred alongwide areas of reclaimed coastal land facing Tokyo Bay.
The following special feature on the Great
East Japan Earthquake introduces disastrous
seismic damage and restoration/reconstruction efforts in the field of construction:• Highway bridges• Elevated expressway bridges• Railway bridges• Port and harbor facilities• Steel-structure buildings
In closing, restoration and reconstruction
measures employing the “new structural system building” are proposed:• New structural system buildings employing
innovative structural materials

Photo 1 Tsunami damages

Photo 2 Ground liquefaction

Great East Japan Earthquake

Highway Bridges
By Takashi Tamakoshi
National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure, Transport and Tourism
The Great East Japan Earthquake caused
many incidences of great damage in which
highway bridges installed in coastal areasor across rivers were washed away by the
associated tsunami (Photo 1). But, thenagain, in areas where the tsunami heightwas confirmed to have exceeded that of abridge’s superstructure, many of thesebridges were not washed away. In addition,
there were cases in which the earthworks
adjoined next to a bridge section were
washed away by the tsunami, while thebridge structure itself remained in place(Photo 2). Currently, surveys and other research on the mechanism of tsunami-generated bridge damage are being promoted
in many fields.
In cases where damage was caused byseismic motion, there is no confirmation of
fatal damage leading to bridge collapse inbridges built in accordance with the design
standards contained in Specifications for

Highway Bridges (issued after 1996 in response to the Great Hanshin Earthquake of1995) or reinforced based on those standards. On the other hand, in unreinforced
bridges, damage such as the buckling andfracture of superstructures members was
confirmed, as was damage to bridge piersand bearings (Photo 3), as observed in previous large-scale earthquakes. In addition,even when damage to a bridge structure
was slight, there were many examples oflevel differences of the road surface produced by the sinking of back-filled soil ofa bridge abutment inhibiting the quick recovery of traffic functions.
In this earthquake, it was confirmed thatground liquefaction occurred in a wide areaof the coastal zone and caused damage tohousing. However, among highway bridges, no remarkable damage due to liquefaction was confirmed in bridges conforming
to design standards issued after the imple-

mentation of new seismic design codes in1971 that contain design specs for the prevention of liquefaction. Meanwhile, damage did occur in some bridges installed inconformance with technical standards issued before 1971.
Soon after the earthquake, efforts weremade to secure emergency transport routes
by repairing level differences of the roadsurface and restoring collapsed embankment, removing debris, and using emergency assembly bridges (Photo 4). Temporary bridges were installed in washed-out
bridge sections and emergency restoration
work was undertaken on damaged bridges.
Currently, the main highway networks
have nearly returned to normal operations,excluding those in tsunami- and radiationravaged areas. Studies and other work
aimed at permanent recovery will be continuously pursued and accelerated.

Photo 1 Washing away of superstructure

Photo 2 Washing away of earthwork in the front and rear of bridge

Photo 3 Damage of top lateral bracing of through Langer arch bridge

Photo 4 Emergency assembly bridge
March 2012 Steel Construction Today & Tomorrow 8

Elevated Expressway Bridges
By K azuo Kaneda
East Nippon Expressway Company Limited
Around 14:46 on March 11th, 2011, the M9
Great East Japan Earthquake, the largest everobserved in Japan, struck off the Sanriku coast.
Strong tremors from the quake were felt overa wide range extending from Tohoku to Kanto.
In Kurihara, Miyagi Prefecture, a reading of 7
(the maximum value on the seismic intensity
scale of the Japan Meteorological Agency)
was recorded. Intense seismic activity wasmeasured on various expressways: the highest
was 6.3 at the Mito-Minami interchange of theKita-Kanto Expressway, while 6.2 intensity
was recorded at the Taiwa and Izumi interchanges of the Tohoku Expressway and the
Sendai-Higashi interchange of the Sendai-Tobu Expressway.
Fig. 1 shows the spectral acceleration responses associated with the Great East Japan
Earthquake and recorded in the vicinity of the
Sendai-Tobu elevated bridge of Sendai-Tobu
Expressway. At the Sendai-Higashi interchange and K-NET Sendai where 6.2 wasmeasured on the seismic intensity scale, thespectral acceleration response reached nearly
the same level as the standard spectral acceleration response of design seismic motion level 2 (Type II) in the vicinity of a natural periodof 1 second. Meanwhile, regarding the seismic
motion observed on expressways, the peak
spectral acceleration response was on the shortnatural period side (in the vicinity from 0.2 to
0.5 seconds) at many sites. The following introduces the damage and emergency restoration conditions of the Sendai-Tobu elevatedbridge that suffered damage characteristic tosteel bridges.
The Sendai-Tobu elevated bridge, locatedbetween the Sendai-Higashi and Sendai-Ko­
kita interchanges, is a continuous elevatedbridge with a total length of 4,390 m that
opened to traffic in 2001. The area of thebridge that suffered the greatest damage consisted of 2 sections—a continuous 4-span steel
girder bridge (P52~P56) and a continuous
2-span steel I-girder bridge (P56~P58). As regards the support conditions for these bridge
sections, in the case of level 2 seismic motion,
elastic support is adopted along both thebridge’s longitudinal axis and the perpendicular axis for all bridge piers, and joint protectors(level 1) are installed for the perpendicularaxis.
Photos 1~2 show the damage to the Sen­
dai-Tobu elevated bridge. The earthquake
caused fracturing of the rubber bearings of theP52 and P56 piers at the girder-to-girdercrossed sections, and, further, fracturing anddeformation of the joint protectors of nearly all
the bridge piers. Residual displacement wasobserved in the bridge superstructure—theamount of deviation being about 15 cm in the
direction perpendicular to the bridge axis in
the P52 pier, and about 50 cm in the direction
perpendicular to the bridge axis and about 40
cm vertically in the P56 pier. From this, it isbelieved that deformation surpassing the fracture strain of the rubber bearings occurred in
the superstructure. In addition, there were observed traces of contact of the expansion de-

Fig. 1 Spectral Acceleration Responses
Design seismic motion level 2 (Type I) II Soil Seed
Design seismic motion level 2 (Type II) II Soil Seed
Great East Japan Earthquake K-NET MYG013 Sendai (NS)100000Great East Japan Earthquake K-NET MYG013 Sendai (EW)

Spectral acceleration response (gal)Great East Japan Earthquake IC observed wave Sendai-Higashi (NS)Great East Japan Earthquake IC observed wave Sendai-Higashi (EW)

Photo 1	Damage of rubber
bearing (P56)

10000

1000

100

10
0.01

0.1

1

Natural period (s)9 Steel Construction Today & Tomorrow March 201210

Photo 3	Installation of temporary
bentvise in the direction perpendicular to the bridgeaxis. Because the bearing height of the boxgirder rubber bearings is greater than that ofthe I-girder rubber bearings and because thedeformable level of the box-girder rubber
bearings in the direction perpendicular to thebridge axis is high, the deformation of the I
girder was caused by that of the box girder, andas a result, the rubber bearings were likely tocause the fractures. Meanwhile, because thebridge collapse-prevention device was installed in the direction of the longitudinal axis
at the girder-to-girder crossed section, bridge
collapse did not occur.
Just after the earthquake, a bent was installed (Photo 3) and vertical stiffeners wereweld-joined to reinforce the girder, and, further, emergency temporary support work using saddles was implemented. Then the girder
was straightened and returned to its original
position using a jack for temporary support(Photo 4), and, further, a rubber bearing conforming to the original design was manufactured and re-installed. In this way, the emergency restoration work for the Sendai-Tobu
elevated bridge was completed. The design
made by reflecting the cause of rubber beating
fracture is planned to adopt in the full-scale
restoration of the bridge.
In the Sendai-Tobu elevated bridge, damage occurred to the seismic horizontal force
distribution-type rubber bearings. This damage was not found anywhere else in Japan. To
this end, an examinationcommittee was established to clarify the causeof the fracturing. The
committee will do a simulation analysis using
three-dimensional nonlinPhoto 2 Residual displacement
ear dynamic analysis emafter earthquake (P56)
ploying site waves andwill confirm the elongation capacity of the rubber
bearings and the material
quality of the rubber used.
When the study is completed, the cause of thefracturing and other examination results will be
Photo 4 Temporary support
made public.

Great East Japan Earthquake

Railway Bridges
By S hinichiro Nozawa
East Japan Railway Company
The Great East Japan Earthquake of March2011 caused the damage of railway facilities throughout a wide area.
On the Tohoku Shinkansen super-express line, the collapse of electrification
posts and elevated RC railway bridges andother types of damage occurred along a
500-km stretch from Omiya Station to
Iwate-Numakunai Station. Photo 1 shows
the damage inflicted on a pin bearing of the
Kakyoin Bridge, a 73 m-long composite
girder bridge located at the Sendai Station
terminal. The pin fractured from the center.
During the restoration work, the pin wasused as it was, and the girder and the bearing were returned to their original position
and a device was attached to restrict movement solely to the direction of the bridge’s
transverse axis. While a large aftershock
occurred on April 7, the entire Tohoku
Shinkansen line resumed operations on

April 29, 49 days after the Great East Japan
Earthquake occurred.
Existing railway lines also suffereddamages in a wide area extending from the
Tohoku region to the Kanto region. Photo
2 shows the slippage of a girder on the Daiichi-Kyuchu overbridge located at Kashima Jingu Station of the Kashima Line. The
bridge is installed with a skew angle ofabout 60° at the composite girder of thebox-girder section. While it was found thatrotational behavior occurred due to the horizontal seismic motion of the skewed girder, the previous completion of girder seat
expansion work prevented the bridge fromcollapsing. Most existing railway lines, excluding those in tsunami-damaged areas,
resumed operations by the end of April
2011.
The tsunamis caused serious damage torailway facilities. Among the damaged fa-

cilities, the Ohamagawa Bridge on the
Hachinohe Line suffered only comparatively slight damage, while four 10-m
spans of the deck steel plate girders were
washed away by tsunamis (Photo 3), andthus it was decided that the bridge would
continue in use, with some restoration
work. While some of the structural members were replaced, most of the deformities
in the girders were corrected by means ofheating, and the girders were re-installed intheir original position in December 2011
(Photo 4).
The entire Hachinohe Line is slated toresume operations in the spring of 2012.
Plans call for the restoration of other tsunami-damaged railway sections under an integrated restoration scheme involving
town buildings to be promoted by national
and local governments.

Slippage

Photo 1	Damage of pin bearing and slippage of composite girder (Sendai
Station terminal, Tohoku Shinkansen)

Flown girder

Photo 3	Outflow of bridge girders due to tsunamis (Ohamagawa Bridge on Hachinohe Line)

Photo 2	Slippage of skewed girders (Kashima
Jingu Station, Kashima Line)

Bridge girder after repair

Photo 4	Installation of repaired girders (Ohamagawa Bridge
on Hachinohe Line)
March 2012 Steel Construction Today & Tomorrow 10

Port and Harbor Facilities
By Mitsuyasu Iwanami
Port and Airport Research Institute
On March 11, 2011, an M9 ocean trench-type
earthquake, the Great East Japan Earthquake,occurred with an epicenter in the Pacific
Ocean off the coast of the Tohoku area. Triggered by the earthquake, huge tsunami wavesof unprecedented scale attacked the coastal
areas of East Japan, causing massive destruction. In port and harbor facilities, damage,collapse, displacement and other disastrous
events occurred in breakwaters, piers, quays
and other port facilities in a wide area extending from Aomori Prefecture to Chiba Prefecture.
Two major features punctuate the current
earthquake: very strong seismic motion, as
seen in the highest maximum acceleration
ever recorded in the strong-motion earthquake observation in port and harbor areas,and seismic motions of long duration. In addition, because the tsunami waves that attacked the coast were larger in scale thanforecasted in the design of disaster-prevention facilities, civil engineering and building
structures, including port and harbor facilities, suffered serious damage. (Refer to Fig. 1
and Photo 1)
A characteristic type of damage found insteel port and harbor structures after the current earthquake is the disruption of interlock-ing joints of steel sheet piles of sheet-pile- Level 2 tsunamis, such as the one that accomtype quaywalls, causing the collapse of the panied the current earthquake, these facilities
quaywalls (Photo 2). The cause of the col- must protect human life as a matter of course
lapse is thought to be the uplifting forces and and prevent fatal damage to structures and,hydraulic forces that acted on portions dam- further, possess sufficient “toughness” to preaged by seismic forces occurring in the steel vent serious secondary damage to structures.
sheet piles and apron pavement. This damage On top of this, for Level 2 tsunamis, disastercan be defined as typical of disasters caused prevention measures should include not only
by complex earthquake-tsunami events.
facility improvements but also supplementaFurther, in the current earthquake, not ry measures such as the preparation of refuge
only the existing breakwaters at Hachinohe, facilities, escape routes and strengthened
Kuji, Miyako and Soma Ports suffered tsu- warning systems.
nami damage, but the breakwaters installed at
the mouths of Kamaishi and Ofunato Ports to Reference
prevent tsunami damage also suffered greatly 1) S. Takahashi et al: Urgent Survey for 2011
Great East Japan Earthquake and Tsunami(Photo 3).
Disaster in Port and Coast, Technical Note of
In order to securely protect human life andPort and Airport Research Institute, No.1231,
assets from huge tsunamis, an important task
2011.4for the future will be to improve breakwaters,
seawalls and other disaster-preFig. 1 Results of Surveys of Tsunami Heightvention facilities. Table 1 shows
41 ˚Nan example of performance matrix
Hachinoheagainst design tsunamis for disaster-prevention facilities1). AccordKuji
40 ˚N
ing to the table, for Level 1 tsunaMiyako
mis, disaster-prevention facilities
Kamaishi
are required to securely protect
Ofunato39 ˚Nhuman life and assets and to withKesennuma
stand all structural damage. For
Ishinomaki
SendaiTable 1 Example of Required Performances against Design Tsunamis
TsunamiScale (occurrence probability)

Performance requirements

Level 1

Largest in recent years(about once in 100 years)• Protecting human life
• Protecting assets• Maintaining economic activities

Level 2

Expected maximum(about once in 1,000 years)• Protecting human life
• Mitigating economic loss
• Preventing large secondary damage• Allowing quick restoration

38 ˚N

37 ˚N

Soma

Onahama

HitachiNaka
36 ˚N

Run-up height140 ˚E

Photo 1 A vessel that ran onto the quaywall

11 Steel Construction Today & Tomorrow March 2012

Submerged height

KashimaPhoto 2 Collapse of sheet-pile-type quaywall

141 ˚E142 ˚E

0

5

10

15

20

25

Photo 3	Collapse of breakwater installed fortsunami disaster prevention

30

Great East Japan Earthquake

Steel-structure Buildings
By Isao Nishiyama
National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure, Transport and Tourism
Disastrous Earthquake of Unprecedented Scale
The Great East Japan Earthquake (moment
magnitude: 9.0) that occurred on March 11,
2011, was the largest thrust quake ever observed in Japan. The hypocenter of the quake
lay in the Pacific Ocean off the Sanriku coastline. The quake, also called the 2011 Earthquake off the Pacific Coast of Tohoku, occurred at the boundary between the North
American Plate on which the Tohoku area ofJapan lies and the Pacific Plate that subducts
the North American Plate. As of November 14,
2011, the number of deaths stood at more than
15,000 and the number of fully destroyedhouses and other buildings at about 120,000.
According to the hypocenter model1) (Fig.
1) released by the Meteorological Research Institute of the Japan Meteorological Agency,
the area of the hypocenter of the Great East Japan Earthquake extends lengthwise about 450
km in a south-north direction and laterally
about 150 km in an east-west direction, off thecoasts of Iwate, Miyagi, Fukushima and Ibaragi Prefectures. Seismic intensity of about 6(out of a maximum of 7 on the seismic inten-

sity scale of the Japan Meteorological Agency)
was recorded throughout wide areas of these
prefectures.
With particular reference to steel-structurebuildings, this article introduces an outline of
the seismic motion and tsunami damages2),3)
associated with the current earthquake and describes the extensive efforts being promoted
towards restoration and reconstruction.
Outline of Damage to Steelstructure Buildings● Damage due to Seismic Motion
Visual surveys conducted on steel-structurebuildings in Sendai City, Miyagi Prefecture—
located relatively near the epicenter—foundalmost no serious damage such as building
collapses, only instances of slight damage
such as fallen non-structural members (Photo1). Damage to building structures was of thestandard type, such as the breakage of exposedcolumn bases and the buckling and fracture ofbraces. While brittle fractures are known tohave occurred in the vicinity of beam-end web
scallops in steel-structure buildings during theGreat Hanshin Earthquake of 1995 (Photo 2),

Photo 1 Falling of non-structural members

Photo 2	Example of beam-end flange fracturethat occurred in a great number in the
Great Hanshin Earthquake

Fig. 1 H ypocenter Model in the Great East Japan Earthquake, Prepared by Meteorological Research Institute of Japan Meteorological Agency1)
42˚

Hypocenter time function

ERIMO

0
IWTH0840˚

IWTH13
IWTH14

MYGH04
MYGH12
MYGH06
MYGH11
MYGH0836˚

Observation points used in the analysis

22

Mo = 3.4 x 10 Nm (Mw9.0)

IBRH13
HITACH
IBRH1530

IYASAT
HANNOU

0
km
0

140˚

5 10 15 20 25

Sliding amount (m)TENNOD
NAGARA138˚

Photo 3 Damage of bearing

Center of respective small faults

FKSH17
FKSH19FKSH12KATASH

200

Destruction staring point in
the current earthquake
Epicenter of earthquakes with M7 ormore after March 9, 2011 in the current earthquake
Epicenter of earthquakes with M5 or
more in a day after occurrence of the current earthquake

IWTH21
IWT00738˚

100(seconds)

142˚

100

200

144˚

Intervals between contours: 4 m

Photo 4 Falling of ceiling
March 2012 Steel Construction Today & Tomorrow 12

The National Institute for Land and Infrastructure Management in collaboration with the
Ministry of Land, Infrastructure, Transport
and Tourism has already made public tentative
seismic countermeasures against long-period
seismic motions4). Triggered by the current
earthquake, the Institute is promoting the verification of these countermeasures and is working to make them the effective standard as
quickly as possible.
Assuming the occurrence of a great earthquake in the Nankai Trough, it is said that longperiod seismic motion elements would be amplified by the trough’s accretionary wedge.
Accordingly, there is a pressing need to prepare the above-mentioned effective standard.
The design natural period of the above-mentioned high-rise building was 5.3 seconds, but
the building experienced resonance due toseismic motion with a predominant period of
7.0 seconds, thereby exposing a problem pertaining to the seismic modeling of buildings.

there has been almost no confirmation of suchdamage in the Great East Japan Earthquake.
This may be because, according to the survey
results, these brittle fractures are regarded as
being nearly non-existent.
Visual surveys seeking steel-structuredamage were conducted on a total of 65 school
gymnasiums in Ibaragi Prefecture, because 1)
gymnasiums are public buildings subject to interior surveys, 2) gymnasiums are similar in
structure to plant and warehouse buildings and3) the seismic intensity registered in Ibaragi
Prefecture was nearly identical to that in Miyagi Prefecture. The damage suffered by joints
connecting RC columns to steel-frame roofs(bearing section) is cited as typical (Photo 3).
As regards the fallen non-structural members
observed in Sendai, ceiling damage was particularly notable in the gymnasiums (Photo 4).
In addition, the standard types of damage wereobserved: buckled vertical braces and fractured joints; deflection, buckling and fractureof horizontal braces installed on the roof plane;
and cracking of concrete cover at column bases.
Many factors may be involved in the damage, but the main causes seem to be the following two: localized forces produced by seismic
motion with a dominant short-period element3)
worked on the joints between different kindsof structural members, and the huge scale ofthe current earthquake that resulted in repetitious seismic motions of long duration.
In the Great East Japan Earthquake, a highrise building in Osaka, 700 km away from the
hypocenter, continued vibrating for 10 minutes or more due to resonance (Fig. 2). Similar
problems associated with long-period seismic
motion were observed at various sites as well3).

● Damage due to TsunamisAmong the loading effects that tsunamis canexert on buildings are tsunami wave pressure,scouring, buoyancy and collision by drifts. In
the Great East Japan Earthquake, tsunami
wave pressure worked as a force to form yielding mechanisms on RC wall structures just as
illustrated (Photo 5), and, further, it caused
fractures in the column base welds of steelstructure buildings (Photo 6). Scouring due totsunami flow deeply excavated soil aroundfoundations, causing building inclination(Photo 7). In contrast to RC-structure buildings, steel-structure buildings whose exterior
members fractured at an early stage were difficult to form air accumulation inside the

Photo 5 Yielding mechanism formed on RC wall

Photo 6 Fracture of column base weld

Photo 7	Inclination of RC-structure building due
to scouring

Fig. 2	Response of High-rise Steel-structure Building in Osaka in Long-period Seismic Motion in Great East
Japan Earthquake3)
Pseudo Vel. Resp. Spectrum (h=5%)01F(NS)
01F(EW)
01F(UD)
10

10

10

/s
/

s)

5

40

20

1(

1
0.

1

1(

0.5
0.1

Disp. Response Spectrum (h=5%)cm

Pseudo Velocity Response (cm/s)

60

0

10

01F(NS)
01F(EW)
01F(UD)

Displacement Response (cm)

50

cm

)

0.5

1
Period (sec)05

Pseudo velocity response spectrum

13 Steel Construction Today & Tomorrow March 2012

10

0

5
Period (sec)

Displacement response spectrum

10

Great East Japan Earthquake
Fig. 4 Numerical Values Indicating Tsunami Loading
Effect Obtained by Back Calculation from On-site
Survey Data6)16

Photo 8	Overturning of steel-structure building
due to floating

Measured inundation depth η m(m)14
No damage (fence and other structures)
Inclination (fence and other structures)
Collapse (fence and other structures)
Remaining (building)Collapse (building)

12
10
*2

8
6

*1
4
2
0
0.0

Photo 9 Damage due to collision by drift

Fig. 3 C alculation Method for Tsunami
Wave Pressure in the Guidelines
of Cabinet Office5)
Building

3hqz = pg(3h – z)

In the newly proposed provisional Guidelines6), even in cases when the effect of the
breakwaters mentioned above might be expected, a value two times the inundation depth
was finally shown. Although a value of twotimes inundation depth has sufficient allowance, this value was proposed by taking into
account the indeterminacy of the tsunami runup simulation that determines the hazard map(map of assumed inundation depths). Becauseof this, improvements in analytical technology
are strongly called for.

hz

Designinundation
depth

1.0
2.0
Water depth coefficient α(inundation depth at the time of being equivalent tostructural strength/Measured inundation depth)

3pghbuilding, and thus rarely suffered overturningcaused by interaction with buoyancy (Photo8). The collision of drifts with buildings could
be observed from the residual deformation
seen in steel columns (Photo 9).
The Guidelines for Tsunami Refuge Buildings prepared by the Cabinet Office5) prescribes tsunami wave pressure (Fig. 3). In the
Guidelines, an expedient is proposed in which
virtual static water pressure is three times theheight of the design inundation depth and is assumed to work only on one side of a building.
By verifying buildings damaged by the tsunami that was generated by the recent earthquake, the value of 3 shown in the expedientwas found to actually be around 0.6 to 1 times6)(Fig. 4). This seems to be attributable to theconstruction of breakwaters; and, even in cases when a breakwater was partially broken, it
effectively worked to reduce the tsunami wave
flow velocity.

Toward Restoration and Reconstruction
Most of the areas subjected to the tsunami disaster associated with the Great East Japan
Earthquake had previously experienced the
Meiji-Sanriku Great Tsunami and ShowaSanriku Earthquake Tsunami. It is natural thatthe lessons learned from these past tsunami disasters should be fully utilized in the restoration and reconstruction projects currently being promoted, and thus the means to relocate
towns and villages to higher ground are abundant. However, it is quite natural that engineering should play a more significant role when it
comes to effectively utilizing spacious landthat is likely susceptible to inundation. Specifically, a means is conceivable to employ pilotis for the lower stories of buildings in order toavoid tsunami wave pressure as much as possible. Another means is to securely support
buildings with piles to prevent overturning due
to scouring. These and other engineering approaches will make it possible to build structures that can sufficiently resist tsunamis invulnerable areas.

3.0

The proposal of laws tobuild tsunami disaster-prevention areas was decided at
a Cabinet meeting held at
the end of October 2011. In
addition, diverse movements toward restoration
and reconstruction are progressing rapidly. It is strongly hoped that positive responses to these movements
are steadily being promoted
by not only the building
construction field but otherfields as well.
Lastly, I would like to express our condolences tothose who have suffered in
the Great East Japan Earthquake.

References
1) Meteorological Research Institute of the Japan Meteorological Agency: Estimated Distribution of Fault Sliding in the 2011 Earthquake off the Pacific Coast of Tohoku—
Analysis Using Near-source Strong Seismic
Waveforms, Apr. 26, 2011 (revised)2) National Institute for Land and InfrastructureManagement: Summary of the Field Survey
and Research on “The 2011 off the Pacificcoast of Tohoku Earthquake” (the Great East
Japan Earthquake), Technical Note of
NILIM No. 647, Sept. 20113) Isao Nishiyama et. al.: Building Damage by
the 2011 off the Pacific Coast of Tohoku
Earthquake and Coping Activities by NILIM
and BRI Collaborated with the Administration, Pre-proceedings of 43rd Joint Meetingof US-Japan Panel on Wind and Seismic Effects, UJNR, Aug. 29-30 20114) Building Guidance Division, Housing Bureau, Ministry of Land, Infrastructure, Transport and Tourism: Tentative Seismic Countermeasures against Long-period Seismic
Motions, Dec. 21, 20105) Examination Committee on Guidelines for
Tsunami Refuge Buildings, Director Generalfor Policy Planning (Disaster Prevention),
Cabinet Office: Guidelines for Tsunami Refuge Buildings, June 2005
6) Building Guidance Division, Housing Bureau, Ministry of Land, Infrastructure, Transport and Tourism: Supplementary Knowledge concerning Design Method for Safe
Building with Structural Strength for Tsunamis, Nov. 17, 2011

March 2012 Steel Construction Today & Tomorrow 14

New Structural System Buildings Employing Innovative Structural Materials— Proposal to Use These Buildings for Restoration and Reconstruction —Association of New Urban Housing Technology
The Japan Iron and Steel Federation
Japanese Society of Steel Construction
New Structural System Buildings Employing Innovative Structural Materials is agovernment-private sector tie-up R&D
project that was promoted from 2004 to
2008. Specifically, the project was promoted jointly by the major Japanese steelmakers and general contractors in conjunction
with the Cabinet Office; the Ministry of
Economy, Trade and Industry; and theMinistry of Land, Infrastructure, Transport
and Tourism. The first major target of the
project was to develop “new steel products
having twice the strength of conventional
products.” This was followed by the acquisition of a firm base for the practical use oflong lasting structures made of the new
structural system buildings employing innovative structural materials and offering
three characteristic features: the rational
incorporation of different functions within
a building, the possibility of greater flexi-

bility in the alteration of inner structures
after completion, and the reuse of structural members. (Refer to Fig. 1)
Improved Seismic Resistance
The highest priority performance requiredof buildings with a long service life is highseismic resistance. Three major related
premises were incorporated in the development of the New Structural System Buildings Employing Innovative Structural Materials:● The maximum scale of earthquakes occurring during a building’s service life
shall be set at 7 (the highest point on theseismic intensity scale of the Japan Meteorological Agency).
● Buildings shall remain within their elastic range during maxim seismic motion.
● Buildings shall be capable of continued
use after suffering a great earthquake.

Fig. 1 Town Developed with New Structural System Buildings
Safe Disaster-resistant Town
Creation of public refuge on a building rooftop,or three-dimensional space inside a building

New structural system building as
an important base to protect humanlife from great earthquakes

New structural system building asa structure built in a raised areaof town for the protection ofhuman life from tsunamis

Collaborative andstep-by-step development
by diverse developers

Compact city with multiple town streets mutually
linked via evacuation routes

Circulation inside the area of structural members withfewer CO2 emissions and high recyclability● Town with diversified living spaces andfine landscaping

Classification to 10 scales based on the seismic intensity measured
by seismometers (Japan Meteorological Agency)
Seismic
intensity
scale

Seismic resistance targeted by
New Structural System Buildings(Elastic range in seismic intensity
scale of 7)

Currently prevailing design
method1

New High-strength Steel
When funding is high, it is not difficult to
produce “steel having twice the strength ofconventional steel.” However, in the current project, the target was to realize twice
the strength while maintaining market
competitiveness. For that reason, it was decided not to increase the addition of rareearth metals and other alloying elements
and to eliminate or simplify the QT(quenched and tempered) heat-treatment
process. To this end, a new high-strength
steel meeting the originally targeted specifications was successfully developed in the
project by making optimum use of TMCP
(thermo-mechanical control process), currently the most advanced plate-rolling
technology (Fig. 3). TMCP itself is an efficient energy-saving process and thus thishigh-strength steel eliminates building
weight and is conducive to constructing
building structures with fewer CO2 emissions.

● Town efficient in resources circulation

Fig. 2 Seismic Resistance of New Structural System Buildings

Method to determine
seismic intensity scale

The currently prevailing building regulations pertaining to the seismic resistancerequired of common buildings specify thatplastic deformation of structural members
is allowed during seismic motion with aseismic intensity level of 5+, but that thebuilding should not collapse. When compared to this level of seismic resistance, itis easy to understand just how much higher
is the seismic resistance targeted for the
New Structural System Buildings. (Refer
to Fig. 2)

2

3

4

5−

5+

6−

6+

7

No damage (main structures remain in elastic range)
Absorption of seismic energy using vibration-control
damperNo damage(main structures remain in elastic range)

15 Steel Construction Today & Tomorrow March 2012

Causing no
collapse, butallowing damages
ges

Establishmentof advanced
technology

New Structural System Buildings
Employing Innovative Structural
Materials
The new structural system buildings aredamage-resistant, have a long service life,
support variable inner applications, and,further, allow the free addition or removalof structural members. These buildings go
beyond conventional building concepts increating distinct urban buildings that incorporate some urban infrastructure. (Fig. 4)
The huge tsunami generated by the seismic motion of the Great East Japan Earth-Great East Japan Earthquaketion networks.
In tackling the(N/mm )
recent massive diDevelopment
1000
saster, a true natarget
Resource saving
1,000 N/mm
High-strength,tional crisis, exHigh-performance
grade
900
high-performance steel
steel with enhanced(Employing advanced
pectations are highQuenched andeconomical rationality
TMCP technology)
tempered
for restoration and800
Conventional Cost up due to heatreconstruction
800 N/mm
treatment
No heat treatment
700
grade
work that will emHigher strength (energy saving)ploy the extensive
Quenched and tempered
600
achievements ob600 N/mm grade
tained through the500
Conventional strength
500 N/mm gradeconcerted efforts
As-rolled
400
of both govern400 N/mm grade
mental and private
sectors in developAddition of rare earth metal and other alloying elements (higher cost)
ing the new structural system buildquake caused destructive damage to a great ings. These buildings offer the following
number of fishing ports as well as agricul- advantages for reconstruction:tural and urban areas extending up and ● Being composed of strong slender columns produced using steel with twice thedown Japan’s eastern coastline from Tostrength of conventional steel, the framhoku to Kanto. Fatal damage befell noting structure can fend off the massively
only buildings but also all urban infrastrucdestructive force of tsunamis in the lowtures that had been installed to support
er floors and provide structurally safebuilding structures: such as ground, road,
space in the upper floors.
water and sewage, gas and electrical power
supply systems, in addition to communica- ● In contrast to building construction that

Fig. 3	Economical Rationality in Development of
New High-strength Steel
2

2

2

2

2

2

starts after the completion of urban infrastructure provided by civil engineering,
the new structural system buildings allow the rapid commencement and completion of building construction concurrently with the construction of urban
infrastructure.
●T he new structural system buildings allow detailed step-by-step improvementsthat meet local needs by first satisfying
emergency building demands and thenvarying the inner applications to conform to the progress of reconstruction.
(Refer to Figs. 5~7)
In addition to withstanding level-7 seismic intensity within the elastic range, the
New Structural System Buildings Employing Innovative Structural Materials are superior to other buildings in terms of tsunami resistance. They also possess a framing
structure that plays a significant role in andis suitable for reconstruction projects carried out in response to damage caused by
the Great East Japan Earthquake. We intend to appeal the advantages derived from
New Structural System Buildings Employing Innovative Structural Materials.

Fig. 4 Role of New Structural System Buildings in the Reconstruction of New Town
RefugeResidential area on sloped site:
Pilotis structure (high floor type)In building multi-storied housing on
sloped land in the vicinity of an urban
area, the 1st floor is built on pilotis(common space) to alleviate tsunami
damageRefugeRefugeRefugeRefugeCore urban area: Mutually linked raised streets
In reconstructing commercial streets in a core urban
area, the entire area along a street is raised, withhousing, hospitals, community centers and otherimportant urban facilities constructed on the upper
floors. The lower floors accommodate commercial
and business functions.

RefugeHeight of great tsunami

Port area: Multi-storied
industrial facilities
Fishery goods disposal site/processing yard,
warehouse, parking lot and other industrial
facilities are accommodated in the multistoried structure, and are accessed by
vehicles moving up and down ramps.

Fig. 5	Proto-type Model of Distribution
CenterFig. 6	Proto-type Model of Regional
Base

Fig. 7	Proto-type Model of Dense
Urban Area

Distribution center with floors that are easily accessible by cars using two ramps:
Mixed three-dimensional arrangement ofplants and offices capitalizing on high ceilings and large spans—great advantages
provided by New Structural System Buildings

In order to protect the building from greatearthquakes and huge tsunamis, the entire
street level structure is raised, the upper
floors accommodate high-performance administrative and regional disaster-prevention functions, and the lower floors house aparking lot and rental space.

Redevelopment model for a dense urban
area with dangerously inadequate disasterprevention features. Raised street area isdeveloped using New Structural System
Buildings in which the lower floors house
existing commercial and business facilities
and the upper floors accommodate multistoried housing around a refuge square.
March 2012 Steel Construction Today & Tomorrow 16

Symposium and International Events
JSSC Symposium 2011 on Structural Steel Construction
The Japanese Society of Steel Construction(JSSC) has annually held the “JSSC Symposium on Structural Steel Construction”
since 2004. The aim of the symposium is toprovide a venue for the comprehensive integration of all operational results attainedby JSSC’s various committees and research groups and to provide a site for mutual exchanges between members and others engaged in steel construction. In orderto hold a symposium organized to produce
substantial results, elaborate plans andstudies are made jointly by the Public Relations Committee and the Committee for the
Implementation of Symposia.
JSSC Symposium 2011 on Structural
Steel Construction was held in November
2011 in Tokyo. The symposium offeredwide-ranging events through the joint cooperation of the JSSC membership andcommittees and other related organizations. The events included a special lecture,a stainless steel session, a report on the latest movements of ISO/TC167, an engineering session, the presentation of JSSC
prizes and the prizewinners’ lecture, and an
academy session.
The prize-winning structural works andpapers were introduced at the panel exhibition. They were also exhibited at the social
gathering venue using a mobile device sothat they could be seen by many participants.
In order to make the symposium more
appealing and to increase the number of
symposium participants, notice of theevent was distributed not
only by the respective
committees but also via
e-mail. As a result, advance applicants numbered about 350 and thetwo-day total was about
1,000. The symposium
served as a useful site forexchanges between researchers and engineers
working in the steel construction field, and also
for collecting the latest
information on steel construction.
JSSC Symposium on
Structural Steel Construction for 2012 is slated for the 15th and 16thof November, 2012.

Awarding of JSSC President Prizes

Special lecture meeting

17 Steel Construction Today & Tomorrow March 2012

Outline of Symposium Programs
November 17, 2011
Engineering Session, Awarding of
JSSC President Prizes,
Social Gathering

A
M

International
Committee

Technology/
Standardization
Committee

Academy Session

Joint I
(buildingconstruction)

Stainless steel
sessionBridgeAwarding of(civil engineering)
JSSC President
Prizes/Lectureby prize-winners

P
M
Special lecture

Structural
analysis(buildingconstruction/civilengineering)

Joint II(buildingconstruction)

Structuralmember I(beam)(buildingconstruction)

Loading capacity(civil engineering)

Fatigue/Fracture(civil engineering)Social gathering

November 18, 2011
A
M

Vibration/
Vibration control/
Repair/Seismic
Reinforcement
resistance(civil engineering)(civil engineering)

Structuralmember II(column,brace, etc)
(buildingconstruction)

Vibration control
Maintenance I(building(civil engineering)
construction)

Framing I(buildingconstruction)P
M
Hybrid andcomposite
structure(buildingconstruction)

Greeting by JSSC President
Koichi Takanashi

Social gathering

Maintenance II(civil engineering)

Framing II(buildingconstruction)

Symposium and International Events

The Grand Prize of AIJ 2011 to Emeritus Prof. Koichi Takanashi
Emeritus Prof. Koichi Takanashi of The
University of Tokyo (President of the Japanese Society of Steel Construction) wasawarded the Grand Prize of AIJ (Architectural Institute of Japan) 2011.
This prize is the most prestigious givenby the Architectural Institute of Japan andis presented to individual members whose
achievements contribute to the advancement of architecture and structural engi-

neering. His distinguished achievements
are diverse: initiatives over many years of
research in the fields of plastic design, seismic design and limit-state design in steel
construction in Japan, and internationallyacclaimed contributions to the promotion
and practical use of standards and specifications. These achievements led to his selection for the Grand Prize of AIJ 2011.
Dr. Takanashi (right) receives the Grand Prize of
AIJ 2011

Fazlur Khan Medal of CTBUH to Emeritus Prof. Akira Wada
Emeritus Prof. Akira Wada of the Tokyo
Institute of Technology was awarded theFazlur R. Khan Lifetime Achievement
Medal of the Council on Tall Buildings and
Urban Habitat (CTBUH) for 2011.
This prize was established in 2004 incommemoration of the achievements ofDr. Fazlur Khan who designed a succession of high-rise building structures incorporating new concepts, as represented by
the John Hancock Center in Chicago. Dr.
Wada has long promoted extensive research in architectural technology and seismic engineering as well as the practical application of the results of that research.
These efforts have contributed to the development of seismic design for high-risebuildings not only in Japan but abroad.

High international praise for these achievements led to his being chosen to receive
this award.

Dr. Wada (left) receives the Fazlur Khan Medalof CTBUH

Lecture by Dr. Wada to commemorate his award

The Robert H. Scanlan Medal to Prof. Yozo Fujino
Prof. Yozo Fujino of The University of Tokyo was awarded the Robert H. Scalan
Medal of the American Society of Civil Engineers (ASCE).
The Scanlan Medal was inaugurated in
2002 by the Engineering Mechanics Institute of ASCE to commemorate Prof. Robert H. Scanlan’s lifetime contribution in thefield of engineering mechanics. It is a prestigious prize presented to individuals who
attain remarkable and extensive achievements in the field of engineering mechanics
based on scholarly contributions to boththeory and practice, and the area of achievement will generally be structural mechanics, wind engineering or aerodynamics.
Further, it is an open prize given without
regard for ASCE membership or national-

ity. Past Japanese recipients were Emeritus
Prof. Masaru Matsumoto of Kyoto University and Prof. Masanobu Shinozuka of the
University of California, Irvine.

The medal was given in high recognition of the great contributions made byProf. Fujino in the areas of dynamics, windeffects, soundness evaluation and active/
passive control
technology pertaining to bridges.

Mr. and Mrs. Scanlan and
Dr. Fujino

Dr. Fujino (center) receives the medal

The Robert H. Scanlan
Medal
March 2012 Steel Construction Today & Tomorrow 18

To Our Readers
As a representative of the Japanese Society of Steel Construction (JSSC), I would like to begin by expressing my sincerest
sympathy to the victims of the Great East Japan Earthquake. On
this occasion, we are committed to extending our maximum
efforts for reconstruction and support in close cooperation
with those working in steel construction in Japan. Further, we
would like to express our deepest appreciation for the warmhearted support received from many foreign countries.
Starting with issue No. 26 of Steel Construction Today & Tomorrow, JSSC’s International Committee assumed responsibiliBy Masatsugu Nagai
ty for the editorial planning of one of the journal’s thrice-anChairman of International
nual issues. Since its inauguration, JSSC has promoted surveys,
Committee, JSSC
(Professor, Nagaoka
research and technological development to promote the use of
University of Technology)
steel construction and to improve steel construction technologies. At the same time, JSSC regularly extends cooperation torelated organizations overseas.
Following the merger of JSSC with the Stainless Steel Building Association of Japan in
2010, JSSC’s field of operation expanded to include not only carbon steel but also highly
corrosion-resistant stainless steel. Consequently, we intend to actively transmit information
throughout the world related to a wider range of steel construction areas.
As was true in issue No. 32, the current issue, No. 35, leads with an announcement of
the 2011 JSSC President Prize and Thesis Prize winners. A special feature treats the Great
East Japan Earthquake: specifically, damage to steel structures due to the quake, aftershocks and the tsunami, and subsequent restoration and reconstruction work. Other major
topics included the presentation of awards—the Grand Prize of AIJ 2011 to JSSC President
Koichi Takanashi, the Fazlur Khan Medal of CTBUH to Prof. Akira Wada and the Robert H.
Scanlan Medal to Prof. Yozo Fujino—and a description of JSSC Symposium 2011 on Structural Steel Construction, which is held annually with support from the JSSC membership, its
related committees, and related organizations.
The International Committee, while working on multi-faceted responses to the internationalization of steel construction codes, promotes exchanges of technical information andpersonnel with overseas organizations. As one aspect of these operations, we inform ourreaders of JSSC operations, trends in steel construction, and the technologies and technological development involved in the planning, design, and building of steel structures inJapan through this “Special Issue on the Japanese Society of Steel Construction,” which is
published as one of the three annual issues of Steel Construction Today & Tomorrow.
If you wish to obtain more detailed information about the various articles contained inthis issue or to receive related technical information, please do not hesitate to contact JSSC
staff member Hiroshi Sugitani (h.sugitani@jssc.or.jp).
JSSC President Prize-winning works

Cantilevered
box-shaped
steel structure of
Hoki Museum

Spherical
structure at
Nagoya City
Science Museum

Large-roof
sliding method
used for airport
building

Restoration of
the attractivenessof RC building
using steel frame

Special Issue
Japanese Society of Steel Construction
1-4 JSSC President Prizes 2011
Hoki Museum, Nagoya City Museum, Large-roof Sliding Method for Airport Building, Using Steel to Restore the Attractiveness of RC Buildings

5-6 Thesis Prizes 2011
Experimental Research on the Mechanical Behaviors of Multirow High-strength Bolted Friction Joints with Thick Plates; Effects of Welding Conditions on the Charpy Absorbed Energy of
Low-toughness Steel HAZ; Study on the Static Characteristicsof Web Connected Part of WBFW-type Beam-end Connection,
Effects of Various Parameters on the Collapse Mechanism ofPanels with Offset Beam-to-Column Connections of Steel
Structures

7-16 Special Feature: Great East Japan Earthquake
Damages to Bridges, Port Facilities and Buildings, and Their
Restoration and Reconstruction; Highway Bridges, Elevated
Expressway Bridges, Railway Bridges, Port and Harbor Facilities, Steel-structure Buildings; Proposal to Use “New Structural
System Buildings Employing Innovative Structural Materials”
for Restoration and Reconstruction

17-18 Symposium and International Operations
JSSC Symposium 2011 on Structural Steel Construction,Awarding of Prizes and Medals

COVER
Four selections of JSSC President Prizes for 2011:(upper left) Hoki Museum (for details, see page1); (upper right) Nagoya City Science Museum(page 2); (lower left) Large-roof sliding method
for airport building (page 3); (lower right) Using
steel to restore the attractiveness of RC structures (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: Takeshi Oki
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
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.