We have been experienced many natural disasters such as earthquake, flood, Tsunami and so on in the world. It is necessary to develop a new rescue structure to survive from them. We have to consider how to recover a damaged construction or how to rebuilt up a new type of the rescue system as soon as possible after a disaster because time is quite important to save lives after emergent situation. On the other hand, we have created the optimum truss structures by micro-truss approach with a large degree-of-freedom in computing method. This is good skill to form new design for the objection of a light structure or high stiffness under a condition in mechanics. So, we have good idea based on this computing skill to apply to the problem of natural disaster. To design a new emergency bridge which is called as “Mobile Bridge”, we have originally created the formation of the optimization truss by computing mechanics. We realize that it is necessary to develop this mobile bridge as soon as possible for next natural disaster.

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In this study, strength and deformation behavior in steel fiber reinforced concrete (SFRC) and stirrup RC beams, under bending-shear load, is investigated by analytical and experimental methods. In the experimental test, optical measurement method was used. Analytically, a theoretical model for SFRC beams developed by the authors and FEM code was used. The structural response throughout the loading is captured and presented. Strength comparison among SFRC, stirrup and control beam showed that SFRC beam has a better performance. A parametric study on fiber content and shear span to depth ratio variation characterized the strength enhancement in the fibrous beams. Analytical results obtained using the theoretical model and FEM were in accord with the experimental results.

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This paper presents results from experimental and analytical studies on the behavior of double lap joints in pultruded hybrid CFRP/GFRP composites. A number of hybrid FRP coupon and full-scale beam specimens with bolted-only and bonded-and-bolted joints were tested. The results show that a combined use of steel bolts, adhesive bonding and V-notch splice plates in double lap joints was found to be an effective method for joining hybrid FRP composites. The rough surface of V-notch splice plates and adhesive bonding contributes to improve the stiffness of joints. Theoretical analyis was carried out and the results showed a good correlation with the experiments.

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In cold regions, existing tunnels constructed by sheet pile method suffer from frozen damages. In order to estimate these damages, analysis of temperature stress is necessary. This paper presents a method for analyzing temperature stress using cylindrical shell theory taking consideration into temperature distribution in tunnel's lining. The temperature distribution in lining is obtained using theoretical model of heat convection/conduction. The effects of geometrical parameters such as length, radius, and thickness of lining are investigated. Several examples are also compared with other numerical methods based on the cylindrical shell theory.

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This paper presents a closed-form analytical equation for estimating the stiffness of the support of tunnel consisting of shotcrete and ribs. To this end, the tunnel is idealized as a perfectly cylindrical thin shell with two stiffening steel arched supports at ends. The equation is derived by using a cylindrical shell theory for shotcrete and by using a ring theory for steel arched supports. Several numerical examples are given to demonstrate the equation and to investigate the effects of various shell parameters including the thickness and radius on the stiffness of the support. The equation is useful for a better understanding of the characteristics of the stiffness of the support.

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This paper presents a damage evaluation method of RC structures based on a reduction ratio of natural freqency. An ambient vibration monitoring was conducted on full-scale bridge column specimens constructed for a shake table project using E-Defense. The damage levels after the seismic excitations were classified into the safety, the yield, and the ultimate states from the response ductility. The reduction ratios of natural frequency caused by the seismic damage were obtained from the ambient vibration data. The relationship between the damage levels and the reduction ratios of the natural frequency were clarified. The evaluation of the safety, the yield, and the ultimate states can be realized by the combination of the ambient vibration monitoring and visual inspection.

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Rubber materials have been used for the relaxation of impact stresses on the collision of steel members. The use of rubber is considered to be very effective for the stress relaxation through investigations on the progressive wave between members, however, the inference does not take the influence of multiple reflections of the incidence wave in the rubber into consideration. This paper disclosed by employing a wave propagation model that the stress relaxation diminishes as the steel member becomes longer, and the results of the model were verified by collision experiments using Hopkinson bar.

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Measurement of shape is a very fundamental step to experimental mechanics. For example, ultimate strength of shell structures is governed by initial imperfection and crack initiation often occurs at a geometorically irregular point. As numerical simulation get sophisticated, more detailed measurement of shape becomes necessary. In such cases, a traditional vernier or a micrometer is no longer an appropriate tool. On the other hand, the use of a highly accurate CMM is usually overkill for specimens of our interests. The objective of this manuscript is to propose a simple but acceptably accurate shape measurement method for column type specimens. In this method, coordinate measure is achieved without any precisely worked frame but by indirect method.

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In this study, a number of orthotropic steel deck models are studied on their trough rib to deck welded joint at span center with regard to root-deck and root-weld fatigue cracks. It is found that increase in deck plate thickness can prolong fatigue lives of the joints regard to both fatigue cracks. Wheel position has also large influence on fatigue life of the joint. The wheel located between the trough ribs gives less damage to the joint. The longer span of trough rib tends to be more venerable to fatigue than the shorter one for root weld crack, but asphalt pavement of 75mm or 100mm thick makes not much difference in increasing in fatigue lives of the joint when load distribution is considered for half period of the year.

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Development of practical and effective rail track-structure countermeasure is advanced as antiearthquake-measures recently. It's necessary to make sure of its effect beforehand in case of practical use of these track countermeasures. Authors have developed a vehicle-track-structure interaction simulation model that can analyze the effects on running safety by track countermaeasures. The outline of this analysis model is described and several analysis results related to these track countermeasures are shown in this paper.

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Preserving arch bridges, considered to be one of the cultural heritages, as their original state has been one of the difficult tasks need to be solved. This paper describes analytical modeling methods of masonry arch bridges in order to predict their behavior under static loading. A simple masonry wall and a typical arch bridge were analyzed by finite element method based on several modeling methods and combinations of material properties in order to check applicability of analytical results and to confirm the best modeling procedure. The results indicated that reduced modulus of elasticity in tension increased displacments of masonry structures more than 10% and that representing bricks and mortar in analytical mesh did not significantly alter the results.

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The ultimate strength of aluminum alloy plates in compression is investigated considering joining locations by the elastic-plastic large deflection analysis with FEM. The aluminum alloys taken into account are heat-treated A6061-T6 and A6005C-T5 and non-heat-treated A5083-O. The softening of material and the residual stresses caused by the friction stir welding (FSW) and the MIG welding are introduced in the analysis. It is shown that the joining locations and the width of plate have a great influence on the ultimate strength. The ultimate strength given by the FEM analysis is formulated to compare it with the design curves specified in Eurocode 9. Finally the curves for the ultimate strength of plates in compression considering joining locations are proposed based on this research.

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Long-lived structures require specifications for infrastructures which consist of stainless steels. This paper proposes a buckling design method for compressive stainless steel plates. Firstly, ultimate strength performances of stainless steel plates, which are designed by use of 0.1% proof stress and 0.2% proof stress, are compared on the basis of results of numerical analysis. Secondly, ultimate strength performance of stainless steel plate is compared with that carbon mild steel plate. Finally, taking stress-strain relationship of stainless steel into consideration, ultimate strength curve of stainless steel plate is proposed. The proposed method certifies us of compressive strength of the stainless steel plate in the condition of the same deformation as the mild steel plate.

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Recently, thick flange has been often used in plate girder bridge with a few main girders to carry large bending moment. Since this kind of girder will endure usually to full plastic moment, the enough rotation capacity will be also expected. This paper presents a cross-sectional classification for the plate girder with thick flange, conducting finite element analyses. From the results we propose the new cross-sectional classification for inelastic design, where thinner web will be applicable than that shown in AISI or AASHTO.

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Local corrosion under railway sleeper can be consequently found on upper flange of railway plate girders. Since the local corrosion is not avoidable now, it will be important to evaluate the remaining strength of corroded plate girder. This paper investigates the remaining strength of plate girder with the local corrosion subjected to a patch load by conducting tests and FEM analyses. From results, the following conclusion remarks can be listed; 1) At the collapse, the large out-of-plane displacements appear on a web panel near the patch load, which is almost the same even if the corrosion exists or not exist. 2) The ultimate strength indeed decrease due to corrosion, but the decrease of it is not so large even though the corrosion under railway sleeper progresses on upper flange.

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This paper describes the seismic performance of T-shaped beam-to-column connections on steel rigid-frame piers. To examine the limit state for this performance and evaluation methods thereof based on the elasto-plastic behavior of beam-to-column connections, elasto-plastic FEM was used to parametrically analyze models of actual structures. Consequently, the damage process and buckling modes for beam-to-column connections were clarified, and it was noted that the limit state of these connections in seismic design could be set according to the damage process. Furthermore, this paper proposes yield stress evaluation methods for web panels that take into consideration the limit state of beam-to-column connections and confirms the validity of these methods by comparing analytical and experimental results with calculations obtained by the proposed methods.

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The Rigid Bodies-Spring Model (RBSM) is a generalized model for discrete limit analysis, and assumes a rigid displacement field. For this reason, it cannot find the value of stress in each element. On the other hand, authors developed the Hybrid-type Penalty Method (HPM) which assumes the linear displacement field using the principle of hybrid type virtual work. In this paper, we proposed the method of finding for the stress in each element in RBSM by applying a rigid displacement field to the displacement field of this HPM. Furthermore, we proposed modified RBSM improving a rigid displacement using this result, and examined the accuracy of the solution obtained from some examples of numerical computation by present method.

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The cracks on underground cavern are induced by the many factors. Especially, the major factor is the relative humidity and temperature conditions around underground cavern. In this paper, the cracking behavior of shotcrete around underground cavern is simulated by the finite element code with considering the underground cavern environment. First, the drying shrinkage cracking behavior of a concrete is modeled, and the sensitivity of the numerical parameters of the proposed model is examined. Secondly, the experimental drying shrinkage cracking of a shotcrete is reproduced by the proposed model, and the analysis results are compared with the measurement data. Finally, the safety of underground cavern is discussed.

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In this study, a fundamental study on game theory (Nash bargaining solution) approach to the bridge maintenance planning is presented. When a bridge is repaired at appropriate time, the gain of the bridge is maximized. Annual budget forces the repair schedule to be slid, so balanced modification of the repair planning is searched. Each bridge is considered as a player, and the bridge group gain is maximized at the same time as pursuing the maximization of an individual gain by adapting Nash bargaining solution with proper utility function. Also, it is shown that the maximized product of the sum of bridges' gain and the Nash product of bridges' gain is effective target for repair priority of a certain bridge.

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In the conventional reliability-based design method, it is considered that a structure has only two performance states whether normally operating or break down. In general, however, the performance of structure will vary with several patarns during its life time. In this study, the reliability evaluation of RC highway bridge pier is performed by the time series MSS (Multi-State System) which can be evaluated the reliability of structure with considering several time dependent performances. Concretely, multiple performance states of piers received salt damage are modeled by the time series MSS, and then the reliability is evaluated. Further, their results are compared with the results obtained by a conventional reliability method with considering only binary performance states.

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The purpose of this research is to establish an appropriate program for the long/middle term planning of public activities. This planning should account for various constraints. The previous research attempted to obtain an appropriate solution by applying Genetic Algorithm (GA). However, in the method, the solution obtained may not be optimal due to the lack of diversity among individuals. In this study, an attempt is made to develop a decision support system of the optimal long/middle term planning by using Memetic Algorithm (MA). MA can obtain the solutions which satisfy all constraints by adopting the repair of gene. Numerical examples are presented to demonstrate the applicability of the proposed method through the comparison with GA computation.

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It is necessary to combine actions properly in the performance-based design. Turkstra's rule is often applied; however, it may not be appropriate to follow the rule when actions are correlated such as wave and wind actions for offshore wind turbine. This study discusses the combining method of the correlated two actions. The proposed method evaluates the characteristic values of actions for maximum joint probability under the given probability of exceedance of the combined actions.

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In this study, we proposed the new methodology to evaluate the behavior of a pier with a caisson foundation under strong earthquake by means of a push-over analysis. Firstly, we showed that we can hardly estimate the dynamic response of the pier with caisson foundation accurately using the static analysis without considering the inertial force of foundation. Secondly, we proposed the simple push-over analysis, taking into account the influence of the inertial force of foundation. Finally, we clarified through dynamic and the static analysis that the proposed method estimates the dynamic behavior of the caisson structure in a good accuracy.

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It was found from field measurements on the road bridge that the vibration occurred when a large lorry passed the expansion joints. The dominant frequency was 13.3Hz and lasted for about 1.5 sec. There were observed other peaks at 40Hz and 80Hz. A new type of damper, the impact absorbing momentum exchanging damper, has been proposed to suppress the vibration occurred at the expansion joints. Parametric studies were conducted using a model consisting of the damper and the concrete deck which was impacted by free-fall weights. The model tests show that the new damper is feasible and effective in reducing the vibration amplitude.

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As a bridge health monitoring technique, vibration characteristic estimation method with ambient vibration has been developed. The accuracy of estimated vibration characteristic is remarkably decreased when presuming from the ambient vibration with running vehicle. For analying bridge traffic vibration, each element of the bridge model, the vehicle model, and the road roughness are needed. But, these problems can not be analized easily because of the existence of bridge-running vehicle interaction. In this study, a program, which enables multi-use analysis with interface function, was developed by withdrawing a relation of force and displacement of bridge and vehicle. Accordingly, the accuracy deterioration was verified by the frequency response of bridge-vehicle interaction.

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Locomotion of animals, such as walking and running, is generated and controlled by the central nervous system called as the central pattern generators (CPGs) which are neural networks that can produce rhythmic patterned outputs. Recently, the CPGs framework has been utillized to develop locomotion controllers for autonomous walking robots. Therefore, in this paper, dynamic response analyses taking into account the neural-oscillator-model proposed by Matsuoka are carried out for the pedestrian bridge model. It was confirmed from numerical simulations that the proposed method based on the neural-oscillator model might be one of useful ways to consider the synchronized oscillations on the pedestrian bridges.

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A prestressed concrete stress ribbon pedestrian bridge with external tendons and supports was constructed in Hakusan city. The different structural characteristics from the Morinowakuwaku Bridge are that the prestressing cables are arranged outside of the concrete deck, and also that the concrete deck is supported by shoes at the abutments. A static loading test was performed to confirm the stiffness of the analytical model. Also, vibration tests were carried out to grasp the vibration characteristics and vibration serviceability subjected to pedestrians walking. The results of the vibration tests show that the several vibration modes existed in the critical ranges of natural frequencies for vertical and lateral vibration. An analytical model was made by finite element method. The vibration serviceability of this bridge was confirmed by using the conventional method and foreign method.

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We have been faced with the low-frequency noise problem as one of the environmental problems. It is important to locate a sound source precisely and effectively to decrease the low-frequency noise. Since the field measurement of the low-frequency noise is not easy because of the wind and various disturbances, the new measurement technique to obtain data with high accuracy is necessary. The purpose of this study is to develop a detection system of the low-frequency noise source using hyper-vision technology. It is confirmed that applicability of hyper-vision technology is promising to detect the low-frequency noise source.

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Edge-improved noise barriers are effective in reducing noises in the outdoor space. In this study, the noise barrier with an improved Y-shaped edge is applied to reduce the noise from paving slab cutting machines. A series of numerical analyses are conducted to examine the sound shielding efficiency of the noise barrier with the improved Y-shaped edge. It is found that the branch angle of the Y-shaped edge has considerable effect on the sound shielding effeciency. Sound absorbing materials attached on the Y-shaped edge can reduce the machine noise more effectively.

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In this research, first the microtremor measurement is conducted for the independent RC piers before the superstructure is constructed and for the completed bridge after the superstructure is constructed. The natural frequencies and the damping ratios of the independent RC piesr and the completed bridge are indentified including the effect of the ground condition and the embedded soil around the pier from the microtremor measurement. The analytical models of the independent RC piers and the completed bridge are constructed and the eigenvalue analysis is conducted against the models in order to check the applicability of the analytical models.

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Rayleigh damping is usually employed in conducting the dynamic response analysis of the bridges. However, Rayleigh damping is not always based on the structural damping mechanism. In this paper, the modal damping ratios of the practical viaduct with 6 spans based on Rayleigh damping are compared with the ones obtained from the proposed method by authors in Ref.20). In this case, the several damping models of the foundation part of the viaduct are also examined in applying the proposed damping model which is constructed on the basis of the damping factor of the structural element. The effect of the damping factor of each structural element on the modal damping ratio of the viaduct is investigated through this research.

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The study discusses the correlation between site amplification factor based on earthquake records and microtremor H/V spectrum. Peak frequencies of the two spectra well agree in cases where obvious peaks are observed in the spectra. Empirical correlation study between the peak amplitudes of the two spectra leads to an estimation method of the site amplification factor for a target site where earthquake records are not available, which make use of the microtremor H/V spectrum and the site amplification factor at a nearby site.

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The pseudo-dynamic test method in centrifugal field is proposed. To clarify the effectiveness of the test method, shaking table tests are also conducted. As the result, the proposed pseudo-dynamic test can simulate seismic response considering the inertia dynamic interaction between the soil and the superstructure. The results of pseudo-dynamic test, including the displacement response and the deformation of piles, are good agreement with that of shaking table test. Assuming that hysteretic model of the structure is a nonlinear steel column, it can evaluate the effects of the nonlinear superstructure. In addition, the centrifuge similitude is the same as that of the pseudo-dynamic test. Therefore, the pseudo-dynamic test is a powerful tool for soil-structure interaction.

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This study is aimed to clarify behavior of ductile crack initiation and propagation in steel bridge piers subjected to random cyclic loading, and to verify an evaluation method of ductile crack initiation using a damage index. Dynamic analyses using fiber model are performed in order to investigate displacement response and damage of steel bridge piers. And cyclic tests are carried out and random displacements are determined based on dynamic analysis. By performing finite element analysis using shell and fiber models, hysteretic plastic strain behavior at the base of specimens is clarified, and the ductile crack initiation is evaluated by the proposed damage index.

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The seismic performance of the bridge pier with inner cruciform walls has been invevestigated and the verification method for seismic design of bridge piers with inner cruciform was proposed. In this paper, the verification for seismic performance in viaduct bridge system including the foundation, rubber bearing, the superstructure and steel pier is examined by the dynamic response analysis. Response results of steel bridge pier are evaluated by dynamic/static verification method in longitudinal direction and transverse direction, resepectively. Response displacement of bridge pierare examined. It is suggested that the fixed condition of rubber bearing in transverse direction of Highway Bridge is better than elstic condition of rubber bearing.

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In this paper, bi-directional loading hybrid tests are carried out to examine the response behavior of square shaped steel bridge piers under the prescript ground accelerations in the Design Specification of the Road Bridge. Each of these ground motions has 2 horizontal components. Both unilateral and bilateral excitations are imposed to 2.4m high steel pier models with a 450mm × 450mm section. It is found from the experiments that the bilateral excitation deteriorates the lateral force of the piers compares to unilateral excitation.

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Combined geometrical and material nonlinear static/dynamic analyses using beam elements are believed to be one of the most practical, yet reliable tools in seismic design of steel structures. This sort of analysis cannot take into account local or distortional buckling; however, member flexural bucking is certainly incorporated into the analysis if adequate modeling is made for the structures. In this paper bracing members installed in one and three story rigid frames are analyzed under both cyclic lateral loading and earthquake motion, and from the results most adequate modeling of their end conditions as well as of initial imperfections are discussed.

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The Tokyo Port Seaside Road Bridge is under construction to cross Tokyo navigation channel. Its main bridge is a 3-span steel truss bridge with a center span of 440m. Soil condition of construction site is very soft clay and the steel pipe sheet pile foundation is adopted. To evaluate seismicity of the bridge at vigorous seismic activity area, dynamic response analysis is carried out. The super structure and sub structure is simultaneously modelled to consider interaction of them. Large sectional force and deformation are calculated at truss sections, therefore an isolation bearing consisting of sliding system and rubber buffer is installed between the truss part and the reinforced concrete pier.

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When an extreme earthquake occurs, roads and bridges are fundamental infrastructures to evacuate the affected people and to transport the emergency equipment and materials. For such emergency response, it is essential to detect immediately after the earthquake the severe structural damage that affects the performance of structures. The authors have proposed a method for the quick earthquake damage detection/evaluation of reinforced concrete bridge columns through analyses of shake table test results. To evaluate the accuracy and applicability of the proposed method to actural bridge structures, a series of nonlinear dynamic response analyses were conduced considering the structural properties of soil-foundation and bearings.

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Precast prestressed concrete bridge piers are constructed by piling up bridge pier segments with embedded external steel pipes, installing internal steel pipes in external pipes so that internal steel pipes might penetrate segmental joints, and applying tensioning to prestressing steel and injecting grout.
In this study, a design model was proposed for the prestressed concrete bridge pier with internal steel pipes, and the seismic design method was examined. A scale model of a precast prestressed concrete bridge pier made by trial design was subjected to Level-2 seismic ground motions using a shaking table. The objective was to verify seismic performance of the model and the validity of the design method.

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A retrofit method with using combination of carbon fiber reinforced polymer (CFRP) jacketing and steel plate jacketing are under studied for seismic retrofit of reinforced concrete (RC) bridge piers. A key issue of this method is to ensure the bonding strength of CFRP-steel bonded connection. In this paper, a series of shear bond tests were performed with the purpose to provide basic knowledge for developing a rational design method for the CFRP-steel bonded connection. Bonding behavior between CFRP and steel plate was investigated by discussing the test results on bonding strength, strain distributions in CFRP, interfacial shear stress and the length of effective bond length.

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Recently, seismic retrofit method by continuous fiber for the RC pier is researched to put to practical use. In this work, new seismic retrofit method using aramid fiber rope for RC pier was invesigated in order to build the design method. The loading test was curryed out with the specimen that changed its cross-section shape and pitch of the aramid fiber rope. And we investigated the strengthening effect and its mechanism based on the experimental rusults.

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More than 70 bridges were washed away by the Tsunami caused by the 2004 Off-Sumatra earthquake. 26 bridges were investigated and classified into three ranks as A, B, C according to the damage level.
In girder damage, 13 bridges (50%) were washed away by Tsunami, and the girder suffered the most extensive damaged member of among girder, substructure and embankment. Compared the damage rank with β value (the ratio between resistance of girder and tsunami force affected to the girder which assumed constant velocity (5.0m/s)), it was observed clear tendency between the damaged rank of girder and β value.

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A lot of great damage occurred to road bridges because of tsunami during the 2004 Indian Ocean Earthquake. Tsunami due to the large-scale earthquakes is worried about also in Japan. To clarify the damage mechanism of road bridges by tsunami, we have conducted the hydraulic model tests. In this paper, the reproduction of the hydraulic model tests and the verification of the washout prevention system against tsunami by the numerical analysis are presented. Through the simulation analysis using MPS method, it is found that the result of the hydraulic model tests was able to be reproduced and washout of the bridge girder was simulated well. In addition, it is found that the installation of the shear keys is effective as washout prevention devices.

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To evaluate the wave force to the bridge by the tsunami wave, the experiment was conducted. We paid attention to the shape of the wave and measured the wave force in the experiment. There were two kinds of shape of the wave, and the tendencies to the wave force could be divided into two. In the case of broken wave, the horizontal wave force was bigger than the uplift force. In the case of unbroken wave, the horizontal wave force was smaller than the uplift force. And the horizontal wave force was 2.6 times as large as the hydrostatic pressure, and the uplift force was 0.5 times as large as the hydrostatic pressure in the maximum.

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Since seismic dampers, such as buckling-restrained braces (BRB), are subject to severe inelastic cyclic strains during major earthquakes, low-cycle fatigue property must be carefully examined in order to develop the high-performance seismic dampers that are being investigated by the authors. To this end, five BRB test specimens have been tested under tension-compression cyclic loading, and an empirical equation of Manson-Coffine type for predicting low-cycle fatigue strength has been proposed. In addition the validity of the currently used verification method for low-cycle fatigue of BRBs is examined in view of the present test results.

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This paper presents a result of a series of general investigations into the damage control seismic design of steel bridges. To this end, one of the most efficient ways is found to install energy dissipation devices in bridges, such as buckling-restrained braces (BRBs). In this paper, a series of new performance tests have been carried out for BRBs that have been made with existing H-section braces being wrapped in by a sort of buckling restraining members so that the overall buckling of the braces would not occur.

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Recently, required performances for high-performance buckling-restrained brace (BRB) as a structural control device has been examined. The brace connects rigid connections with the core-end is stable under cyclic loading and is effective as an energy dissipation device. But, it is difficult to design connections as a rigid in rotation, and three or four-hinge instability including connection and core-end is concerned. If the brace including connections becomes instable, BRB cannot fulfill its function as energy dissipation devices. Moreover, design method for these brace connections is not established. In this paper, out-of-plane behavior of various types of a gusset plate connections including bolted joint system tested, and required conditions of the connections for stable BRB's action has been analysed and discussed.

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This study aims at developing a kind of high performance shear panel dampers (SPDs) with maximum shear deformation of 12% and cumulative inelastic deformation of 280%. In this study, stiffened SPDs are analyzed using ABAQUS program together with the modified two surface model developed at Nagoya University for structural steels. The validity of the analytical model is verified by comparing with previous experimental results. Based on both experimental and analytical results, a hysteretic model with good accuracy is newly developed for such high performance SPDs.

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Various kinds of dampers for seismic response control of bridges have been developed. However, there is not unified seismic design method for bridges using structural response control devices. The objective of this parper is to examine the dynamic response of bridges using structural response control devices and to verify the mathematical model. Shake table tests of bridge model using binghum fluid dampers were performed to examine the dynamic responses. The nonlinear dynamic analyses using mathematical model of dampers obtained through cyclic loading tests were performed to simulate the seismic responses. The analytical simulation results showed that the seismic responses were simulated well.

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