13th World Conference on Earthquake Engineering Vancouver, B.C., CanadaAugust 1-6, 2004

FUNDAMENTAL STUDY ON UNIFIED TOOL
FOR STRUCTURAL ANALYSIS USING NETWORK
Motohide TADA1 and Susumu KUWAHARA2
SUMMARY
A lot of applications have been developed by many investigators, and have served for the precise analyses
of member-buckling, local buckling, lateral buckling, and elasto-plastic behavior of various structural
elements. But, as they have been used independently, we cannot analyze coupling effect of each
phenomenon. In this point, we do not fully utilize present analytical applications. If we can unify these
applications, various phenomena can be considered simultaneously in the analysis of whole building
structure.
As the first step to realize above plan, this paper firstly proposes the simple method to transmit the
numerical data through Internet. The elasto-plastic structural analysis of a steel braced frame is then
conducted using several personal computers. Each computer analyzed composite beams, columns, and
braces, respectively by using different applications. The stiffness-matrices of each member are transmitted
to the host computer through Internet. Host computer constitutes the global stiffness-matrix for the whole
structure, and solves the global stiffness-equation. The incremental deformations of each member are
distributed to each computer from the host. Each computer analyzes the next step using the transferred
deformations, and replies the revised stiffness to the host.
The results of the pushover analysis and the earthquake response analysis are shown. The deteriorating
behavior of concrete in composite beams, and the post buckling behavior of braces can be simultaneously
analyzed.

DEVELOPMENT OF EVACUATION SIMULATION SOFTWARE AFTER
AN EARTHQUAKE FOR EARTQUAKE PREAREDNESS EDUCATION
Koichi TAKIMOTO1 Fusanori MIURA2 Tomoko IMACHI3
SUMMARY
Some simulation models have been developed in the field of architecture and civil engineering. However,
these models simulate an evacuation behavior in order to consider prevention plan about spaces such as
underground shopping centers or department stores. It is impossible for people who are not specialists to
simulate evacuation behavior in such places in order to grasp their behavior. Therefore, the author
developed simulation software which users such as schoolchildren and teachers can easily used.
Therefore, the author developed evacuation simulation software for using earthquake preparedness
education by using a personal computer. Furthermore, it was introduced to schoolchildren’s and university
students , and their evacuation behaviors were simulated after the simulation software developed.

CENTRIFUGE MODEL TESTS ON GROUP PILES IN LIQUEFIABLE
AND NON-LIUEFIABLE GROUND
Susumu IAI1 and Tetsuo TOBITA1
SUMMARY
Model tests are performed on group piles in liquefiable and non-liquefiable ground using a geotechnical
centrifuge with a 2.5 m arm length at the Disaster Prevention Research Institute, Kyoto University. The
objective of this study is to obtain an overview on how behavior of a soil-pile system is affected by
difference in the fundamental conditions, such as single or group pile condition, or under static or
dynamic condition (i.e. shaking table tests). Results of the model tests indicate that (1) larger residual
displacements of a soil-pile system are expected during dynamic loading for the same level of inertia
force, and (2) group pile effects are observed in liquefied ground.

SIMPLIFIED ESTIMATION METHOD FOR A SEISMIC RESPONSE
CHARACTERISTIC USING STATIONARY RANDOM RESPONSE
CHARACTERISTIC
Shigeru AOKI1
SUMMARY
Seismic response is nonstationary random process in nature. Mean square value of the response
is one of the most important statistical values. Integral of mean square value of the response
during seismic excitation is defined as seismic response strength. As seismic excitations,
nonstationary artificial time histories are used. An approximate method for obtaining seismic
response strength is proposed. Seismic response strength is obtained for various values of the
damping ratio and natural period and some types of envelope functions. It is found that seismic
response strength obtained form approximate method is equal to that obtained from exact
method.

Case Study On The Soft-First-Story Buildings Strengthened By Confined
Concrete Columns
Hiroshi KOMOTO1, Tatsuo KOJIMA1, Yoshinori MASE1, Kazuo SUZUKI2, Xuefeng WEN3
ABSTRACT
Generally, pilotis buildings are not safe against earthquake as people might expect. However, the
technique of confined concrete to columns and beams of pilotis story will give an approach of solution,
it yields a stable large ductility of such 1/20～1/15 of story drift angle.
In this study, response properties of 10 stories of pilotis buildings for 25, 50 and 75 Kine ground motions
are investigated, analyzed, and sufficiently illustrated what safe responses are..

INVERSION OF SOURCE PROCESS IN CONSIDERATION OF
FILTERED-ACCELERATION ENVELOPE
Masumitsu KUSE1, Masata SUGITO2 and Nobuoto NOJIMA3
SUMMARY
A new inversion technique using filtered acceleration envelope with emphasis on frequency-dependent
properties of source process is presented. The technique uses strong motion prediction model EMPR
(Earthquake Motion Prediction model on Rock surface) developed by Sugito et al. [1] which have been
developed on the basis of the strong motion database. Filtered envelopes for the simulated motions are
calculated for comparison with the observed motions. The least square method is then applied to solve the
best pattern describing the relative distribution of seismic power from elemental sources on the fault
plane. Numerical examples are shown for the inversion of source process of the 1999 Taiwan Chi-Chi
earthquake. Frequency-dependent asperities are obtained for the low, mid, and high frequency ranges; the
first one is consistent with far-field S wave inversion by Yagi et al. [2], the last one being with non-filtered
acceleration envelope inversion. Successful results are also demonstrated in terms of reevaluation of time
histories of non-stationary power spectra and spatial distribution of seismic intensity.

ENERGY-BASED EVALUATION METHOD OF SEISMIC
PERFORMANCE OF TIMBER STRUCTURES
Nobuyoshi YAMAGUCHI1 and Chikahiro MINOWA2
SUMMARY
For the purpose to evaluate seismic performance of timber structures against severe earthquakes like as
1995 Kobe earthquake, it is desired to propose survivability limit state criteria and design method for
them. Shaking table test of timber structures using JMA Kobe motion was conducted, and collapse of
timber structures was simulated physically on the shaking table. Load-deformation curves considering Pdelta
effects and non-linear damping factors were obtained. Dynamic yields and asymmetrical features
were observed in them. Basic asymmetrical hysteresis model for timber structures was proposed. Energybased
evaluation method using capacity of energy absorption was applied to the test results. Process of
energy absorption and distribution in the equation was analyzed. Relationship between capacities of
energy absorption and collapse of structures was clarified. Energy-based design using Housner’s
assumption was verified in shaking table tests. Capacity of asymmetrical hysteresis model is proposed for
survivability limit state criteria. Application of energy-based design for survivability limit state criteria is
discussed.

BASE ISOLATION SYSTEM SUITABLE FOR MASONRY HOUSESShigeya KAWAMATA1, Naoki FUNAKI2, Norio HORI 3, Tomomi FUJITA 4 and Norio INOUE5
SUMMARY
Though it is one of the most urgent subject of earthquake engineering to mitigate the disaster caused by
collapse of masonry houses in developing countries of seismic area, rapid transfer of these houses into
construction of modern engineering is difficult and dependence on local masonry material will prevail
unchanged.
In this paper, a new form of base isolation suitable to masonry houses and apartments is proposed, where
rocking pillars are utilized to support the superstructure. The rocking pillars are formed by a steel tube
with concrete infill provided with spherical bearing caps at top and bottom ends. Only to settle down a
caisson containing the pillar into a hole is the site execution necessary for forming an isolation foundation.
Vibrational characteristics of houses built on the isolation foundation are made clear by theory and
experiments. Shaking table tests are carried out using 1/4 scale specimen of the isolation foundation
system having weights of 2.4 ton. Based on the result of the shaking table tests, capability of the new
system to protect the masonry houses is discussed.

EARTHQUAKE SAFER NON-ENGINEERED CONSTRUCTION PRACTICES:
PROBLEMS AND PROSPECTS
Rajib Shaw1, Kenji Okazaki2 and Eiko Narita2
SUMMARY
Several recent earthquakes in different parts of the world have pointed out the
importance and need to promote a culture of earthquake safer building practices. This is
specifically relevant to the context of developing countries, where the application of building
codes and regulations are often neglected. A specific problem occurs for the non-engineered
buildings, which are made by informal construction sectors, without any monitoring and
inspection process during construction. The success of the earthquake safer construction of nonengineered
buildings is often attributed to the awareness and involvement of the house owners
and masons.
A unique approach is adopted in the reconstruction program after the Gujarat Earthquake
of India in 2001. Initiated by a diverse group of organizations, the approach focuses on the
confidence building of masons and house owners through shake table demonstration testing. A
shake table was designed in the field to test two half-size models at a time using different
construction technologies. Two tests were performed for the rubble masonry using mud and
cement mortar, and one test was performed for the concrete block masonry. Use of retrofitting
technologies using traditional practices was demonstrated in one model, and was tested
simultaneously with the normal model.

EXPERIMENTAL AND ANALYTICAL STUDIES ON THE
STRENGTHENING OF RC FRAMES
Ibrahim ERDEM1, Ugurhan AKYUZ2, Ugur ERSOY3 and Guney OZCEBE3
SUMMARY
Due to various deficiencies and inadequate lateral stiffness many reinforced concrete buildings are highly
damaged or collapsed in Turkey during the last major earthquakes. To improve the behavior of such
buildings and to prevent total collapse, necessary amount of strengthening must be provided. To
investigate and to compare the two types of strengthening techniques of reinforced concrete frames,
namely introducing an infill RC wall, and CFRP strengthened hollow clay tile wall, two 1/3 scaled, 2-
story, 3-bay test specimens are prepared. The frame of the specimens is detailed such that it has the
common deficiencies of existing buildings in Turkey. The test specimens are subjected to reversed cyclic
quasi-static loading. By means of special transducers, axial force, shear force and bending moment at the
base of the exterior columns are measured. Strength, stiffness, and story drifts of the test specimen are
determined. Analytical studies are also conducted. Top displacement response envelope curves of the both
specimens are verified with the analytical pushover results obtained using Ansys 7.0