International Journal of

High-Rise Buildingswww.ctbuh-korea.org/ijhrb/index.php

International Journal of High-Rise Buildings
March 2023, Vol 12, No 1, 93-105
https://doi.org/10.21022/IJHRB.2023.12.1.93

E-Isolation : High-performance Dynamic Testing Installation for
Seismic Isolation Bearings and Damping Devices
Yoshikazu Takahashi1†, Toru Takeuchi2, Shoichi Kishiki3, Yozo Shinozaki4, Masako Yoneda5,
Koichi Kajiwara6, and Akira Wada7
1

Department of Civil and Earth Resources Engineering, Kyoto University, Nishikyo-ku, Kyoto, Japan, 615-8540
Department of Architecture and Building Engineering, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro-ku, Tokyo, Japan, 152-8550
3
Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa, Japan, 226-8503
4
Taisei Corporation, 1-25-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo, Japan, 163-0606
5Department of Architecture and Building Engineering, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro-ku, Tokyo, Japan, 152-8550
6
E-Defense, National Research Institute for Earth Science and Disaster Resilience
7
Tokyo Institute of Technology
2

Abstract Seismic isolation and vibration control techniques have been developed and put
into practical use by challenging researchers and engineers worldwide since the latter half of the20th century, and after more than 40 years, they are now used in thousands of buildings, private
residences, highways in many seismic areas in the world. Seismic isolation and vibration
control structures can keep the structures undamaged even in a major earthquake and realize
continuous occupancy. This performance has come to be recognized not only by engineers but
also by ordinary people, becoming indispensable for the formation of a resilient society.
However, the dynamic characteristics of seismically isolated bearings, the key elements, arehighly dependent on the size effect and rate-of-loading, especially under extreme loading
conditions. Therefore, confirming the actual properties and performance of these bearings withfull-scale specimens under prescribed dynamic loading protocols is essential. The number of
testing facilities with such capacity is still limited and even though the existing labs in the US,
China, Taiwan, Italy, etc. are conducting these tests, their dynamic loading test setups are
subjected to friction generated by the large vertical loads and inertial force of the heavy table
which affect the accuracy of measured forces. To solve this problem, the authors have proposeda direct reaction force measuring system that can eliminate the effects of friction and inertia
forces, and a seismic isolation testing facility with the proposed system (E-isolation) will becompleted on March 2023 in Japan. This test facility is designed to conduct not only dynamic
loading tests of seismic isolation bearings and dampers but also to perform hybrid simulationsof seismically isolated structures. In this paper, design details and the realization of this system
into an actual dynamic testing facility are presented and the outcomes are discussed.

†

Corresponding author:
Yoshikazu Takahashi
E-mail:takahashi.yoshikazu.4v@kyoto-u.ac.jp

Keywords Seismic Isolation, Bearing, Dynamic test, Friction, Inertia force, Scale effect,
E-Isolation

1. Introduction
Looking back on the development of earthquakeresistant structures, there are two main concepts: First, thestrength-based structures, which resist strong earthquakes
elastically, and second, ductile structures which give thestructural members the ability to deform plastically. The
former can be applied to low-rise buildings, but cannot beapplied to mid-rise or higher buildings. Ductile-frame has
been recommended for buildings of all heights and bridges

not only in Japan but also in the U.S., China, Italy, andother seismic-prone countries. Both reinforced concreteand steel structures have been actively studied to provide
ductile behavior and frames with stable plastic deformation
capacity, and many textbooks and design guidelines invarious countries carefully describe these methods. However,
the recommended ductility here is actually obtained byobservable structure damage. Following the ductile
structure concept, even if human lives are secured during
a major earthquake, damaged houses, hospitals, factories,

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Figure 1. High-rise building and large bridge incorporating seismic isolation.

offices, schools, bridges, etc. cannot be used in mostcases, will lose their functions, and in some instances, theyshould be demolished and rebuilt. Since around 1970,
seismic isolated and vibration-controlled structures havebeen developed and put into practical use as structural
methods that minimize or entirely eliminate the damages
in the main structural frame during earthquakes. These
innovative structural methods canalize the plastic energy
on seismic isolation members and energy dissipating
dampers during an earthquake, rather than on structuralmembers such as columns and beams. This way, the main
structural members remain intact after the earthquake, andall building functions or occupation will be uninterrupted.
These techniques have already been widely applied tonumerous high-rise buildings and large bridges, as shownin Figure 1.
Needless to say, seismic isolation devices and dampers
are critical components that govern the seismic responseof a structure, and it is necessary to comprehensively
understand their behavior under a major earthquake
before the design stage and construction. Therefore, it isimportant to conduct dynamic tests on full-scale isolation
devices that closely represent the realistic seismic behavior,simulating all conditions when an actual earthquake strikes aseismically isolated structure. A certain amount of structural
damage is expected according to strength and ductility
based design which has been confirmed during earthquakes
in the last 70 years. On the contrary, the users are expecting
a damage-free performance from seismically isolated
structures even under a severe earthquake. Public understanding is crucial to promote the spread of seismicallyisolated structures, and the synergic effect of these
initiatives will help build a more resilient society.
Among the typical laminated rubber bearings used forseismic isolation, natural rubber-based laminated rubber
bearings (NRB) have a relatively linear force-displacement
relationship, while lead-plugged laminated rubber bearings(LRB) and high-damping rubber bearings (HDRB) withadded damping capacity are known to exhibit complex
behavior under high vertical forces and large dynamic
horizontal deformation and where the performance is also
highly dependent on the member size. Especially, large
rubber bearings of over 1m diameter require longer
production time for vulcanization adhesion and have ahigher risk of defects. Therefore, it is very important toverify the behavior of such seismic isolation bearings
using dynamic testing machines on full-scale specimens.
However, there are no facilities in Japan that can dynamicallytest full-scale laminated rubber bearings over 400 mm indiameter, such as those used for large buildings andbridges. Until now, such tests have been conducted on
testing facilities outside Japan e.g. in the U.S., Taiwan,
etc. Figure 2(a) shows the Seismic Response Modification
Device (SRMD) testing facility (Benzoni et al.,1998) at
UCSD. The moving platen, which induces shear force on
the test specimen, is dynamically moved in the horizontal
direction while being subjected to high vertical forces oftens of thousands of kNs. However, the frictional reaction
at the supporting bearings due to the large vertical force
and the inertial force of the heavy table is mixed into themeasured reaction force of the load cell attached to thehorizontal actuators. Alireza et al. (2019) realized a realtime hybrid experiment by correcting inertial forces bymeasuring acceleration and constructing an accurate friction
model for friction forces. However, it is not easy toaccurately reproduce a complex friction model that depends
on pressure, velocity, phase, and temperature, and thetime delay associated with the calculation also poses achallenge for real-time hybrid experiments.
To solve these problems, the authors are proposing a
direct measurement system, as shown in Figure 2(b), a
substantially large reaction beam is placed on the upperside of the specimen supported by special bearings (laminatednatural rubber isolators) with very low stiffness in thehorizontal direction while almost rigid in the verticaldirection (Kh < Kv / 3000). Unlike regular seismic isolators,

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Figure 2. Comparison of conventional and proposed reaction force measurement system.

these elastomeric bearings don’t have a hole in theircenter which enables them to act like a solid rubber ballsustaining large vertical force. As the layered steel plates
inside the bearing composition don’t have holes either,rubber expansion is restrained and stress concentrations
are prevented effectively. Reaction force measurement
links are horizontally connected between the reaction
beam and the rigid RC reaction wall. Majority of thehorizontal reaction force is measured in real-time throughthese force-measurement links, and since the reaction
beam moves minimally, almost no inertia force is generated.
Furthermore, by supporting the reaction beam with elastomericbearings, only 1-2% horizontal force is transmitted
through the support layer. Since laminated natural rubber
isolator bearings are expected to exhibit linear properties,
even under small horizontal deformations of a few mm
and large vertical loads, these horizontal forces transmitted
through the bearings can also be accurately captured. To
keep the bearings under compression, pre-tensioned PC
strands are provided, while the horizontal stiffness with
their P-D effects can also accurately be captured because
their tension forces are unchanged.
Although this concept of eliminating the effects offriction by measuring the reaction force on the reaction
side has been used in frame testing in the past, there arefew precedents for the use of this approach in full-scale
dynamic testing machines by arranging multiple loadcells between a test piece and a reaction beam (Shimoda,
1990s, Zayas, 2023). But our design concept of thesystem follows the “design axiom” proposed by MIT
Professor Nam P. Suh (Suh, 1990). In any design, there
are a set of functional requirements (FRs) and a set ofdesign parameters (DPs) to be determined by the design.
The relationship between them is expressed by a design
matrix (A) as “FRs = A*DPs”. The design matrix A is avery complex, but it can be simplified by organizing the
problem and incorporating new ideas. The design matrix
A for a force data acquisition system to insert many loadcells between the test machine and the specimen iscomplicated, and it is difficult to improve the accuracy ofhorizontal load measurement because the load cells,
which are subjected to large compressive forces, mustmeasure a horizontal force of about 10% of the verticalload. In this proposed method, the design matrix A can bemade into a simple diagonal matrix because the reaction
beam is supported flexibly in the horizontal direction andthe horizontal load is measured by four horizontal links
that are free in the vertical direction. As a result, theaccuracy of horizontal force data acquisition can be improved.
With the collaborations with a group of researchers, theauthor team is currently constructing Japan’s largest fullscale seismic isolation bearing test facility incorporating
this proposed system (Figure 3).
In this paper, detailed design for incorporating this
proposed measurement system into an actual large dynamic
testing facility is introduced and discussed. The processof integrating a new idea into a real device requires a vast
amount of research and iterations, and these processes arepresented and discussed along with the details of thedesign for each component.

2. Proposed horizontal force measuring system
At first, reaction force measuring systems in existing
dynamic testing machines are outlined and frequently
observed shortcomings of those systems are clarified. In
the commonly implemented reaction force measurement
system shown in Figure 2(a), the top plate of the seismic
isolation bearing specimen is fixed to a large steel beam(e.g. SRMD in UCSD, Benzoni et al.,1998) or a concrete
frame (e.g. MATS in NCREE, Lin et al., 2017). Meanwhile,the bottom plate of the specimen is connected to amoving platen on horizontal bearings with vertical loading
capability to conduct performance verification tests byapplying a prescribed dynamic horizontal deformation
protocol. The horizontal reaction force of the tested
seismic isolator specimen is measured by a load cell seriallyconnected to a horizontal dynamic actuator. However,during the dynamic loading of the seismic isolation
bearing subjected to high level axial forces, the frictional
forces in the horizontal bearing of the moving platen andthe inertial forces generated by the mass of the platen
itself are merged into the measured horizontal reaction
force values. The inertia force can be estimated by measuring

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Figure 3. Real-size dynamic testing facility under construction.

the acceleration and multiplying it with the mass of themoving platen but calculating and eliminating the effectsof the friction force is quite challenging because friction
depends not only on the constantly changing vertical forces
but also on velocity, phase, temperature, and otherparameters. In Alireza et al. (2019), a sophisticated friction
model is proposed, and a real-time hybrid simulation is
attempted, however, the friction force has not been
entirely eliminated.
The reaction force measurement system proposed inthis paper is outlined in Figure 2(b) and Figure 3 whichshows the plan and cross-sectional views of the proposed
experimental set-up. The new testing facility just constructedin Japan, Hyogo, Miki besides E-defense facility (Figure4) has a vertical load capacity of 36,000 kN (static),
30,000 kN (dynamic), stroke limit of 250mm and velocity
capacity of 70 mm/sec. In the horizontal direction,
dynamic single directional loading capacity is 6,500 kN(static), 5,100 kN (dynamic) with ±1,300 mm stroke limit
and the max velocity is 800 mm/sec. In this testing system,a big steel reaction beam is placed above the specimen
similar to the SRMD facility in UCSD, but this time it is
supported by laminated natural rubber bearings with low
horizontal stiffness and high vertical stiffness, instead ofbeing fixed to the RC reaction walls. The reaction beam
is connected to a horizontally rigid RC reaction wall bya V-shaped measurement link with built-in load cells anda couple of rotational-constraint measurement links withbuilt-in load cells also. The two transverse beams at bothsides of the reaction beam are pulled down withhorizontally-free PC strands (steel strands for precast
concrete) of 14.6 m length between bottom and top
anchors that apply compressive force to the laminatedrubber bearings so that the compression force on thesebearings is not lost even when the reaction beams are
subjected to lift-up effects during the experiments. Becauseof the low horizontal stiffness of the rubber bearings
supporting the reaction beam, majority of the horizontal
force is measured through the reaction measurement link,
where the ratio of horizontal force transmitted through thelaminated rubber bearings is less than 1%. Due to thereliable elastic characteristics of the laminated natural
rubber bearings, horizontal forces in these bearings canbe accurately included in the resultant reaction forces byusing their horizontal deformation. Since the horizontal
displacement of the reaction beam is expected to be in thevicinity of 1-2 mm and acceleration is at a negligible
level, in principle, the measured forces should not beaffected by the frictional or inertial forces, which havebeen an issue in existing facilities.
Design details of each component realizing this system
are discussed in the following sections.

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Figure 4. Plan and section of real-size dynamic testing facility in Japan.

3. Design and construction of RC reaction wall
A part of the detailed design drawings of RC reaction
wall is shown in Figure 5. For a future extension to
50,000 kN vertical loading capacity with a two-dimensional
horizontal moving platen, the RC reaction wall has been
designed to withstand these conditions with 9.90-11.00 m
clear span. The thickness of the reaction walls is 3.50 m
and the foundation thickness is 4.5 m. Prestressing is
implemented in the foundation and walls, for preventing
cracks in these concrete walls.
The reaction beam is placed on the RC reaction walls
supported through twelve laminated natural rubber

bearings with 650 mm diameter. PC strand sets consistingof 12 × φ12.7 mm strands are connecting the reaction
beam onto the RC reaction walls. Four of these PC strand
sets are provided for each bearing with a design pre-stresslevel of 1050 kN on each (1240 kN in construction,
considering future relaxation). Pre-stressing forces aredesigned to keep the support rubber bearings undercompression even under the most severe testing conditions.
To allow the expected horizontal movement of thereaction beam, PC strands have been placed in sheathtubes with 190.7 mm diameter. 5.3 mm thickness, allowing
47 mm clearance in the design stage around the PC
strands. The 11.52 m tall sheath tubes are precisely

Figure 5. Plan and section of RC reaction wall with PC strand arrangement (Courtesy of Kurosawa Construction)

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Figure 6. PC strands construction anchoring the reaction beam.

installed into the RC reaction walls within 1/650 error
margin, using template frameworks as shown in Figure 6(a). As result, 30mm clearance around the PC strands issecured (Figure 6(b)).

4. Design and fabrication of steel reaction
beam
The reaction beam consists of four steel box beams
with section of 2.5 m height, 1.2 m wide, 9.1 m long,
22 mm to 30 mm in thickness and 20 tons weight, andtwo more box-shaped beams of 1.25 m wide, 7.2 m longand 26 tons weight on each end connected in an H-shaped
plan, as shown in Figure 7. The six beams are transported
individually and assembled at the construction site byfriction bolt connections. In addition, large plates of
30 mm of 4.8 m width and 8.4 m length are bolted on the
top and bottom of the connected boxes for integration.
Design of the reaction beam was carried out starting withsimple calculations followed by sophisticated finite element
analysis, and it was confirmed that each component was
kept below the allowable stress level for the steel materialand slip load of the bolts, where the design verticaldeformation was 7.6 mm (1/1450), and the torsional angle
was 1/759 under vertical load of 30,000 kN and horizontal
load of 6,000 kN.
To ensure the quality of each friction bolt connection,
comprehensive tolerance controls were conducted during
the fabrication of the reaction beam. During the assembly,
the warping caused by welding was minimized and the

Figure 7. Plan and section of reaction beam. (Courtesy of Nippon Steel Engineering and Dr. Hidemoto Mukai)

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99

Figure 8. Fabrication and installation of reaction beam.

tolerance of the friction joint was successfully obtained tobe less than 1 mm (Figure 8).

5. Design and fabrication of force measurement
links
The key component of the proposed system, theFigure 9. Reaction-force measurement link.

reaction force measurement link, consists of a V-shaped
measurement link intersecting the center of the reaction
beam and a couple of rotational constraint measurement
links, as shown in Figure 4(a). 4MN and 1.5MN loadcells are mounted on the V-shaped link, and the rotational
constraint link, respectively. V-shaped measurement links
restrain the displacement of the reaction beam in the x

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Figure 10. Elastomeric isolator supporting the reaction beam.

and y directions, and the individual reaction forces alongx and y directions can be obtained by multiplying cosine
and sine components on axial forces respectively. Hereafter,
x-axis is defined as the main loading direction and y-axis
is defined as the orthogonal direction in plan, where zaxis is the vertical direction as shown in Figure 4(a). To
restrain the rotation of the reaction beam about the z-axis,
a couple of rotational constraint links are added between
both wings of the reaction beam and the RC reaction
wall. Conducted analyses indicate that up to 75% of the
major reaction forces will be resisted by the V-shaped
measurement links and the remaining by the rotational
constraint links. The additional reaction forces measured
by these links are expected to be 99%.
V-shaped link should be able to keep up with thevertical displacement of the center of the reaction beam
under a vertical force of 30,000 kN within the elastic
range, and the shear force and bending moment applied to
the load cell must be controlled within the allowable
range. For this reason, joints with reduced bending
stiffness at both ends are used for these links. This method
effectively reduces shear forces and bending moment asshown in Figure 9. This joint is hereafter referred to as an‘elastic pin’.

6. Elastomeric isolator supporting reaction
beam
Twelve 650-mm-diameter natural rubber laminatedbearings (rubber shear modulus G = 0.39 N/mm2, horizontal
stiffness for small amplitudes k = 1.1 kN/mm, total stiffnessof 12 bearings is 13.2 kN/mm) were employed for supporting
the reaction beam as shown in Figure 10(a). As indicatedin Figure 10 (b), sliding bearings such as ball bearings orhydrostatic bearings generate frictional reaction forces,
which fluctuate instantaneously and frequently dependingon the phase of motion, making it difficult to determine
the friction forces by using displacement data. Conversely,
natural rubber isolator bearings exhibit relatively low
horizontal stiffness, and as long as linear behavior isensured, the reaction force can be accurately determinedfrom the very small displacement. Micro-deformation
experiments were conducted on candidate laminated rubber
bearings during the design stage to confirm the stabilityof their linear behavior.
Besides, 48 PC strands of 12 m × 5/6 (fixed ends)-

Figure 11. Configuration of moving platen (Courtesy to Mitsubishi Heavy Industries Machinery Systems)

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101

Figure 12. Restraint systems for moving platen. (Courtesy to Mitsubishi Heavy Industries Machinery Systems)

effective length (4 strands per support) between thebottom of the reaction beam and the bottom of RC wallwith 1240 kN of tension force each exhibit a horizontal
stiffness of 6.0 kN/mm in total due to their PΔ effect. As
result, total horizontal stiffness at supporting bearings is
expected to be approximately 19 kN/mm only. Therefore,
the horizontal forces induced by these bearings are expected
to be substantially small relative to the measurement
links, namely less than 1%, and can be accurately
evaluated by measuring the horizontal displacement of
the reaction beam, which is approximately 1-2 mm undermaximum force 6,000 kN.

7. Configuration of the moving platen
As shown in Figure 11, the moving platen consists ofa lower layer that moves vertically and an upper layer thatmoves horizontally in the x-direction. The lower platen iscontrolled by 24 vertical dynamic jacks while the upper
platen is supported on the lower layer by linear sliders
with 18 rails and 14 sliders on each rail (total number ofthe sliders of 252), moves in the x-direction by 4 horizontal
dynamic jacks.
As the vertical jacks are simply supporting the moving
platens, there is no restraining measure against partial
uplift as a result of the rotation about y-axis and x-axis.

Also, they don’t resist against z-axis rotation or y-axis
displacements. Therefore, 4 leveling jacks restrain x-axis
and y-axis rotations, and 4 backup arms are provided tolimit z-axis rotation and movement in the y-axis. Furthermore,
4 horizontal dynamic jacks are angled slightly (10° fromx-axis) to control y-axis movement and z-axis rotations(Figure 12). The leveling jacks are linked with crossconnected oil chambers which stabilize the horizontal
level without obstructing the vertical movement of themechanism as shown in Figure 12 (c). Total 28 numbersof vertical load cells are provided on the vertical jacks
and leveling jacks, and total vertical reaction force (Fz),rotational moment around x-axis (Mx) and rotational
moment around y-axis (My) can be obtained from thesevalues.

8. Test jigs for various specimens
Testing jig images for seismic isolation bearings andenergy-dissipation devices are shown in Figure 13. Not only
seismic isolation bearings but short column specimens up
to 2.1 m height can also be assessed by this testing device.
For energy-dissipation devices, an additional load-cell
unit consisting of three flat load-cells is attached on the
RC reaction wall, and by setting the specimen between
this load-cell unit and upper moving platen, reaction

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Yoshikazu Takahashi et al. | International Journal of High-Rise Buildings

Figure 13. Testing jigs for various specimens.

forces will be directly measured eliminating the effects offriction and inertia forces similar to the measurement linksystem.

less than 1%, which is considered to be a closer agreement
when the reaction force of the bearing supporting thereaction beam is also taken into account.

9. Preliminary test for measurement link

10. Hybrid simulation capability

Prior to the completion of the facility, preliminary
experiments were conducted to confirm the accuracy ofthe proposed reaction force measurement link. Specifically,an oil jack and load cell were installed in serial between
the upper moving platen and the bottom of the reaction
beam as shown in Figure 14(a), and a horizontal load ofup to 1000 kN was applied by the oil jack, while the loadcell readings were compared with those of the reaction
force measurement link system. Part of the results areshown in Figure 14(b). The sum of reaction force measured
by the measurement link and forces transferred through12 rubber bearings with P-D effect of the 48 PC strands
are parallelly captured by the load cell with an error of

The hybrid simulation (Hakuno et al., 1969, Nakashima
et al., 2020) was proposed in Japan and is now widelyused in the world to simulate the seismic response oflarge-scale structures. It is an experimental method that isused to deform a structural specimen as if it were responding
to an earthquake ground motion using an online computercontrolled simulation of dynamic response. In hybrid
simulation, one member or part of a structural system isbuilt experimentally while the remaining parts are modeledusing a computational model and the equation of motion
for the structural system is solved by time integration
schemes. The restoring force characteristics of theexperimental part are obtained by data acquisition from

Figure 14. Preliminary test for measurement link.

E-Isolation : High-performance Dynamic Testing Installation for Seismic Isolation Bearings and Damping Devices

the force sensor of the physical test run in parallel to theanalysis. Especially, real-time hybrid simulation (RTHS)
is an efficient method to evaluate the dynamic responseof structural systems with rate-dependent devices.
Since the proposed facility has a direct reaction force
measurement system eliminating the effects of friction
and inertia forces, the precision of hybrid simulation canbe substantially improved. The servo-controller in thisfacility has a hybrid simulation mode to communicate
with computational kernels (ex. OpenSees) in real-timeby OpenFresco (Takahashi et al., 2006, Schellenberg),
which provides a high-speed, low latency data communication
between the servo-controller and the analytical computer
by reflective memory (GE Intelligent Platforms 5565PIORC
product family).

11. Conclusive remarks
In this article, a just-constructed dynamic testing facility inJapan, specifically designed for seismic isolation bearing
tests, eliminating the effects of friction and inertia forces
was introduced. Presented discussions are summarized asfollows.
1) A method was proposed to determine the frictional
and inertial forces mixing into the measured reaction
forces in the dynamic testing systems, by using a
direct measurement link that measures the reaction
force was proposed.
2) Design of a fully pre-stressed RC reaction structurethat can withstand 30,000 kN vertical force waspresented, including the details of the reaction beamconnected by PC strands allowing horizontal
displacement.

Figure 15. E-Defense and E-Isolation in Hyogo, Japan.

1033) Design and fabrication of steel reaction beam
consists of six steel box sections spanning 11 m waspresented. Special fabrication and assembly wereconducted to prevent distortion caused by welding
and ensure required tolerances.
4) Reaction force measurement link system consistingof two V-shaped links and two rotational constraint
links is proposed. These links are expected to capture
majority of the reaction forces without the effects offriction and inertia forces which was unavoidable inconventional facilities. An elastic pin connection was
proposed to obtain accurate measure-ment following
the vertical movement.
5) Laminated natural rubber bearings are chosen forsupporting the reaction beam due to their low
horizontal stiffness and elastic behavior that allows
to clearly identify the reaction forces.
6) Moving platen configuration including various
stability systems was presented.
7) Test setup configurations eliminating the effects offriction and inertia forces are introduced not only forseismic isolation bearing tests but also for energydissipation devices/dampers.
Preliminary experiments were conducted to confirm theaccuracy of the proposed reaction force measurement
link, and it was confirmed that the error margin is lessthan 1%.
The ability to accurately measure the specimen reaction
force in real-time is expected to be a significant advantage
for real-time hybrid simulations using this system.
Dr. M. Yoneda proposed and we have agreed to callthis new facility “E-Isolation” after it’s neighbor andsibling facility “E-Defense” which was established in

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2005 (Figure 15). We are hoping this location is bound to
become one of the main centers of earthquake engineeringin the world.

Acknowledgment
This work was supported by Council for Science,
Technology and Innovation (CSTI), Cross-ministerial
Strategic Innovation Promotion Program (SIP), Enhancementof National Resilience against Natural Disasters (Funding
agency: National Institute for Earth Science and Disaster
Resilience). The authors would like to express their
deepest gratitude to all those who contributed to thisresearch project including Cabinet office, Ministry ofLand, Infrastructure, Transport and Tourism (MLIT), Ministryof Education, Culture, Sports, Science and Technology(MEXT) of Japan and National Research Institute for
Earth Science and Disaster Resilience (NIED). First, weappreciate those who strongly encourage and support us
to construct the new facility, Governor Tomohiko Saito,
Hyogo Prefecture, Mayor Kazuhiko Nakata, Miki City,and President Kazuya Masu, Tokyo Institute of Technology.
In particular, we would like to thank to Dr. Yoshiaki
Nakano, Mr. Takahito Inoue, Ms. Tomoko Sakaguchi
from NIED, Dr. Keita Uemura, Mr. Tomoya Ueda from
Kyoto University, Dr. Yuki Terazawa, Dr. Miku Kurosawa,
Mr. Ichiro Hirano, Mr. Sachio Umemura, Mr. Kazushi
Sakai, Ms. Maho Kobayashi from Tokyo Tech.
We also deeply appreciate the project team who
proceeded the design, fabrication, construction, andassembly in an extremely short period of time, including
Taisei Corporation, Kozo Keikaku Engineering Inc.
(KKE), Mitsubishi Heavy Industries Machinery Systems
Ltd., Nippon Steel Engineering Co., Ltd., Fuso Kiko,
Kurashiki Kako Co., Ltd., Kurosawa Construction Co.,
Ltd., Mukai Structural Design Office, Koizumi I. W. Inc.,
Kanden Plant Corporation, Japan Society of Seismic
Isolation (JSSI), Japan Seismic Isolation Laboratory(JSIL).
Especially we thank to Dr. Ichiro Nagashima, Dr.
Tsutomu Komuro, Dr. Ryota Maseki, Mr. Kyohei Ueda,
Ms. Yukimi Sahoda, Mr. Ko Endo, Mr. Wataru Mimura,Mr. Takahiro Nakajima, Mr. Masayoshi Takazawa, Mr.
Yusuke Noguchi, Mr. Shinnosuke Okayama, Mr. Taisuke
Masuno, Ms. Ayumi Suzuki, Mr. Yasuhiro Ueno, Mr.
Yuki Kobayashi, Mr. Takumi Koike, Mr. Yutaka Saito,
Mr. Kohji Yoshida from Taisei Corporation, Chairperson
Shota Hattori, Dr. Guo Xianqun, Mr. Naoya Goto from
KKE, Mr. Masayuki Shimizu, Mr. Masayuki Suetsugu
Mr. Shohei Ikari from Mitsubishi Heavy Industries
Machinery Systems Ltd., Dr. Hidemoto Mukai and Mr.
Manabu Koizumi, and Dr. Yasushi Ichikawa, Mr. Atsushi
Watanabe, Mr. Mitsuharu Sakai from Nippon SteelEngineering, Mr. Masayuki Gurita, Mr. Kohji Higashiyama
from Kurashiki Kako, President Masaaki Watase, Mr.
Shuji Murasaki, Mr. Kazuaki Aso from Fuso Kiko, Dr.

Ryotaro Kurosawa, Mr. Tsukasa Kashiwazaki from
Kurosawa Construction, Mr. Hiroshi Morikawa from
Kanden Plant, President Akinobu Nakazawa, Mr. Nagahide
Kani, Mr. Yoshihisa Kitamura from JSSI, Mr. Takaaki
Miyabara, Mr. Kazuo Ebihara, Dr. Shoji Hayasi, Dr.
Kazuo Tamura, Mr. Kenji Sawada from JSIL, Mr. Hidemi
Niinai, Mr. Yuichi Kojima, Mr. Masanobu Hayashizaki
who support experiments and operation, and Dr. Andreea
Dutu from Technical University of Civil Engineering of
Bucharest, Dr. Fatih Sutcu from Istanbul Technical
University for their advises.
This project was realized by the support of many people
involved in research, design, and construction related toseismic isolated and vibration controlled structures inJapan. We would like to mention a few names here to
express our gratitude. In fact, the project is being carriedout with the support of vast time contribution of thisgroup of engineers.
Distinguished Professors;
Dr. Tsuneo Okada, Dr. Masao Saitoh, Dr. Toshio Nishi,
Dr. Katsuki Takiguchi, Dr. Hirokazu Iemura, Dr.
Katsunori Kaneda, Dr. Teruhiko Yoda, Dr. Yozo Fujino,
Dr. Haruyuki Kitamura, Dr. Masayoshi Nakashima, Dr.
Toshiharu Kanebako, Dr. Toshimi Kabeyasawa, Dr.
Masaru Kikuchi, Dr. Hiroyasu Sakata, Dr. Hideo Fujitani,
Dr. Mineo Takayama, Dr. Mitsuyosi Akiyama
Outstanding structural engineers in general contractors,
other companies and organizations;
Mr. Tadashi Hayashi, Mr. Kazushi Ishizaki, Dr. Kunio
Ukai, Mr. Osamu Hosozawa, Mr. Tominari Miwa, Mr.
Masayuki Yamanaka, Dr. Hideo Katsumata, Dr. Tuyoshi
Sano, Mr. Tsutomu Arai, Mr. Takayuki Sakakima, Dr.
Akira Fukukita, Mr. Kazuo Kojima, Mr. Yasushi Kurokawa,
Dr. Akihiko Kondo, Dr. Masahiko Higashino, Mr. Hiroyuki
Ueda, Dr. Masashi Yamamoto, Mr. Hirotaka Sekido, Mr.
Toru Tuchihashi, Mr. Takahiro Kido, Mr. Hideo Kobayashi,
Mr. Shigeki Sugiura
Distinguished material engineers in rubber bearing
supplier;
Dr. Nobuo Murota, Dr. Masahiro Nakamura, Mr. Naoki
Kato, Mr. Mitsuru Miyazaki

Disclosure
The authors have no conflicts of interest to declare.

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