The largest surface ground acceleration(124.5gal) was recorded on the surface(k1) and bedrock(-30m depth:k6) of the Tokyo Metropolitan University observation station at Zushi-site during the 2011 off the Pacific coast of Tohoku Earthquake(M=9.0).
 From these data, the dynamic characteristics of the surface ground of Zushi-site were examined and the structure model of the surface ground was identified by the developed identification analysis using the observed data (k1&k6).
 Moreover, the three dimensional seismic response analyses of the Zushi-site were performed using k6 for input motions by TDAP III to evaluate the dynamic behaviors of the surface ground.
 The calculated results agreed well with the observed ones.
 These results are useful for the seismic disaster mitigation and seismic designs of the structures and ground in Zushi-site.

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 Water supply facilities such as pumping stations are often located on unleveled ground, and new RC tanks are often constructed in close proximity to existing RC tanks. The influences ground surface inclination and the construction of new structures have on existing structures have not yet been fully explained. This study analyzes the influences ground surface inclination have on surrounding soil and existing structures, and the influences ground surface inclination and the construction of the new structures have on existing structures through a case study monitoring the construction process using 2-D dynamic analysis methods. This study found that in the event of an earthquake the impact on existing structures located at lower ground is small because the effect on the surrounding soil (which is soft and under-going quakeinduced non-linearization) caused by the RC tanks (exhibiting high rigidity and short-cycle vibration) is greater than the effect on existing tanks incurred by the ground surface inclination and newly constructed structures.

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 Seismic vulnerabilities of water distribution pipelines all over Japan were evaluated based on the database of “Statistics on Water Supply” in terms of “vulnerability factors” proposed by the authors. Relationship between vulnerability factors and several statistical indices describing system characteristics of each water supplier was examined. The effect of recent revision of seismic resistant capability of several types of pipe matelials and pipe joints was also considered. The regional disparities of the vulnerability factors were quantified using Gini coefficients, demonstrating a diversity in terms of seismic vulnerability. Long term trend of nation-wide vulnerability factors from 1994 through 2010 was also evaluated.

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 The site amplification factor was evaluated with temporary seismic observation datum at Onikobe area that has relatively small basin subsurface structure. Microtremor measurements were carried out in order to evaluate deep subsurface profile using dispersion curves and horizontal-to-vertical (H/V) spectral ratio. The site amplification factor was compared with the transfer function calculated by two-dimensional seismic response analyses with different incident angles of seismic motion.
 The site amplification factor was in between the average value and the average plus one standard deviation values of the transfer function calculated by two-dimensional analyses. It was regarded as comparatively good agreement considering the range of incident angles of seismic motions used in the calculations of the site amplification factor.

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 Coastal embankment has been constructed to protect coastal area for earthquake and tsunami. But seismic-resistant shortage is pointed out. To improve the disaster prevention performance, seismic countermeasures should be optimized both performance and cost, and evaluated ductility for Huge earthquake hard to collapse. In this study intended for permeable grouting method and examine effect and ductility by centrifuge model tests. It is proved that under the sea wall remarkable share deformation occurs due to liquefaction, so improvement this area is quite effective and seismic-resistant can be optimized. It is confirmed that permeable grouting method has peculiar ductility which primary factor is cohesion. Deformation characteristic is improved to the cyclic shear loading, seepage of pore water is restricted and with dilatancy of soil an effective stress increased and shear resistance became higher.

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 This paper analyzes the factors associated with district victim rate by Tohoku Earthquake Tsunami in Minamisannriku-town, Miyagi Prefecture. Even if it is the same inundation height, it is shown that the rate of a victim has big variation. However, it is unclear that which factors affect the variation. In this paper, we conducted hearing investigation and arranged the rate of a victim and related data.Then we show that sea visibility, whether the 1960 Chile Tsunami reached or not, and a location of momentary evacuation site have affected the district victim rate in addition to the inundation height.

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 This study focuses on the damage mechanism of the Yanoura water-pipe bridge behind roadway bridge during the tsunami in 2011. The superstructure of the water-pipe bridge was flooded away due to breakage of side-block bolts at river-upstream side. Acting force to the side-block bolt of bearing under tsunami inundation is modeled as formulation in this study. The rotation of superstructure and damage to sideblock bolt are evaluated by the ratio of acting force to resistance force using result of the tsunami numerical simulation by Naota et al. As the evaluation result, the rotational moment of superstructure contributes the damage of side-block bolt. When the superstructure is not completely covered with the tsunami wave, the superstructure rotates downstream of river as the actual flooded superstructure did. As the interval of two bridges becomes narrow, the wave force to the water-pipe increase and the side-block bolt becomes more likely to have damage.

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 In this study, simulation analysis was conducted on seismic strengthened Berth No. 5 (-12m) in Onahama Port, selected as a model structure among the port facilities damaged by 2011 off the pacific coast of Tohoku Earthquake. The simulation analyses were conducted by use of FLIP (Finite Element Analysis of Liquefaction Program). In addition, cocktail glass model was used in the program, based on the facts that the wave estimated for Onahama Port after 2011 off the pacific coast of Tohoku Earthquake of long duration was taken as the input seismic motion and that the settlement due to dissipation of excess pore water pressure after liquefaction was occurred at the berth. In the cocktail glass model, the pore water flow during and after earthquake and the drainage conditions such as volumetric shrinkage due to liquefaction can be considered.

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 This study investigates an effect of damping modeling on the dynamic analysis results of masonry structures using a refined version of the distinct element method (refined DEM). The refined DEM can handle two types of damping terms; a damping force acting at a gravity center of each element, and a damping force acting between two elements in contact. To determine appropriate damping terms from several kinds of damping models, it is necessary to understand the difference among damping models. Therefore, this study numerically investigates the difference in free vibration response, failure behavior and collapsing behavior by different damping models. A mass-proportional damping and a local damping are selected as damping terms acting a center of gravity element. In addition, a critical damping and a stiffness-proportional damping are selected as damping terms acting between two elements. Combining these damping terms, three damping models are proposed. By conducting the analysis with these damping models, their characteristics are examined.

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 Sawada et al. proposed a combined RC column with friction damping mechanism and have been examining its practical application through cyclic loading tests. We conducted numerical simulations of the experiment based on three-dimensional elastic-plastic analysis in order to examine the analytical model. To gain good agreement between the experiments and simulations, we needed to append binding forces to that model, because the column was already in damaged condition before loading. We got a better agreement between them by applying a sequence loading to the columns in the simulations, for the specimen had been subjected to a series of cyclic loading in the experiments. However, it is necessary to further improve the analytical model and condition, because in large strain levels in a few cases, the maximum bearing force, hysteresis damping and strain hardening properties of the seismic structure system are different between the experiments and analyses.

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 This paper discusses the mechanism of tsunami-induced behavior of the superstructure with the fairing through a series of flume test and analysis. In the flume tests, 1/20-scaled models of the superstructure with rectangular, two-girders and four-girders section were employed with/without the semicircular or triangular fairing. Test results showed that both types of the fairing effectively reduced the tsunami-induced horizontal and vertical forces applied to bearing supports in all test cases of superstructure. Furthermore, analytical results showed that the significant hydrodynamic pressure was observed at the top of web and the bottom of overhang slab in the conventional superstructure, while such hydrodynamic pressure was effectively reduced by equipping both types of the fairing with the superstructure. The reduction of hydrodynamic pressure results in the mitigation of the tsunami-induced reaction force to the bearing supports of bridges.

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 The Ohkura Dam is the only concrete double arch dam in Japan, which is composed of right arch dam, left arch dam and thrust block. In regard to such structures with complex shapes, seismic safety evaluation based on three dementional dynamic analysis is to be necessary. The seismological observations have been made at the dam, and the earthquake motions have been obuserved before, during and after the 2011 Off the Coast of Tohoku Earthquake. In this study, we made three dmentonal dynamic analysis. We firstly evaluated the dynamic propery values of the dam by reproducing the predominant frequency of the dam. And then, we evaluated the seismic safety of the dam during the 2011 Off the coast of Tohoku Earthquake. As a result, the maximum tensile dynamic stress was estimated to be about 2.9 N/mm² , and it is considerd that seismic safety of the dam has been maintained during the earthquake.

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 In this research, the vibration test employing RC pier model is conducted under various vibration levels, and the change of the vibration properties such as the natural period and the damping ratio is investigated under the respective vibration level. The change of the vibration properties of the entire bridge model with the superstructure is also investigated under various vibration levels. Furthermore, the vibration property of an actual bridge which has two-span continuous superstructure and an RC pier, and its single RC pier without the superstructure are investigated under small vibration level. As a result, a couple of the findings about the change of the vibration property under different vibration level are obtained through the vibration tests.

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 In this study, effects of various properties of the cross joint welding on deformation capacity and energy absorption of steel beam-column connections with weld defects are experimentally investigated. To this end, effects of weld defect width, fillet radius and weld leg length are discussed. As a result, if the crack is growth to the column flange, the effects of fillet radius and weld defect width on the deformation capacity and energy absorption are small. On the other hand, if the crack initiates from the weld defect, the effects of weld defect width and fillet radius become very large.

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 The present study is aimed at proposing a conditional expression of avoiding local buckling in the part of variable sections for steel bridge piers with 3-steps variable stiffened box sections, and developing a design method for such steel piers. For bridge piers with 3-steps variable sections, seismic performance of structures may be inferior because of possible buckling occurring in the part of variable sections compared with those with uniform sections. In addition, when local buckling occurs at the base section in steel bridge piers with 3-steps variable sections, the performance will be better than that of piers with uniform sections. Base on this, a conditional expression for avoiding buckling in the part of variable sections is proposed considering effects of structural parameters from results of cyclic analysis performed on steel bridge piers with variable stiffened box-sectional models. The analytical results show that the positions of buckling and whether seismic performance will be lower or not for steel bridge piers with variable stiffened box sections can be evaluated easily by adopting the proposed conditional expression.

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 Owing to recent progress of aerial survey with laser transmitting device, we can easily obtain detailed digital elevation model represented by point cloud data. This model is applicable to many purposes such as active fault detection, quantification of bluff lines, and extraction of ground displacement caused by an earthquake. Although some methods for seismic displacement extraction from point cloud data have been proposed, we need more robust and powerful method in terms of noise immunity. In this study, we propose a new method based on the RBF (Radial Basis Function) interpolation and the GA (Genetic Algorithm) for the seismic displacement detection and then conduct a series of inquests including the parameter setting, the evaluation of noise resistance, and the comparison among four optimization techniques: GA, L-BFGS-B, Nelder-Mead, and COBYLA. The results of considerations revealed that: (1) the size of unit for pattern matching should be set to 24 m square for the point cloud divided into 1 m grid; (2) the proposed method stably detect the correct displacement even under ill-posed condition; (3) the combination of the RBF and the GA is well suited for this problem because the objective function appearing in this study possesses extreme multimodality, suggesting that we should not use the optimization method based on gradient information.

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 It has been reported that there were many cases of damages at rectangular water tanks in water supply facilities, under Tohoku earthquake. These many cases, wall panels are destroyed. This kind of dameages is thought to be caused by sloshing which is risen by long term earthquake. In this paper, the authors measured water presser by sensors at surface of the wall through experiment with real scale water tank on large shaking table. The purpose is examining an effect on wall by variety of shake direction angle, shake time and shake amplitude and understanding the differences. In the end, we found out some possibility of that the part near corner and roof of tank being structural week point.

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 This study is aiming at clarifying influences of the earthquake and tsunami to a cable-stayed bridge which has caisson foundation. For this purpose, a series of numeric simulations were carried out. First, flow speed, direction and tsunami height were determined by conducting a two-dimensional tsunami analysis of the large area, and they were then applied in a detailed three-dimensional tsunami analysis to obtain tsunami forces. Next, a structural analysis in which the acquired tsunami forces were input into a whole bridge system was performed. As a result, the foundation slide was not observed although the caisson foundation came floating slightly, and damage by the earthquake did not expand in the tsunami. It is concluded that the influence of tsunami force is small. Furthermore, a numerical procedure is proposed for estimating quantitatively the earthquake and tsunami induced compound damage in the whole bridge system which has large-scale caisson foundation.

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 Tokyo Gas Co., Ltd. has deployed a real-time earthquake monitoring system, SUPREME, which employs approximately 4, 000 spectrum intensity (SI) sensors in their service area. Tokyo Gas gathered approximately 60, 000 borehole information, and the amplifications of SI are estimated in their service area. Recently, Metropolitan Seismic Observation network (MeSO-net) has been operated. This study evaluates the site amplification characteristics using the ground motion records obtained by SUPREME and MeSO-net, and the availability of geospatial data compiled by Tokyo Gas is discussed.

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 Aiming for improvement of reliability of earthquake disaster estimation results, an Integrated Earthquake Simulator (IES) is being developed by combining geographical data and simulation methods. In this study, we enhance the original IES, which simulates the response of city using input at bedrock, to fault-to-city simulation by integrating fault models, deep soil structure models, and simulation methods to obtain wave at bedrock. This new system is applied to an urban area of Sendai city which consists of 22,800 structures. We expect that the developed system can be used to evaluate the effects of uncertainties in the input data of each phase of an earthquake disaster to the final structural damage estimation results by running Monte Carlo simulations with different input parameters on high performance computers.

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 The features of tsunami waveforms acting on a bridge subjected to the 2011 off the Pacific Coast of Tohoku earthquake tsunami are clarified. The waveforms are classified into 5 types from view of points of the increasing rate of inundation depth and inclination of wavefront. For 74% of bridges, the increasing rate of inundation depth is less than 2.0 m/min. The relationship between the increasing rate of inundation depth and the slope angles of sea and land areas around a bridge are revealed. The tsunami waveforms with the increasing rate of inundation depth of more than 5.0 m/min require the slope angles of more than 0.01 rad of sea areas and more than 0.05 rad of land areas. Finally, the dependence of the shape of wavefront on the increasing rate of inundation depth is clarified.

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 The evaluation index for the Tomei, Meishin, and Shin Tomei Expressway was considered. First, the soil structure models and structure classifications of the expressway were collected. We developed the basic data every 50 meters using by the soil and structure data. Next, the evaluation index of earthquake resistance priority was examined of the seismic intensity, important degree, and structure characteristics. The important degree define the based on the traffic times of expressway and general way. The Shin Tomei expressway is constructed in parallel with the Tomei expressway. We developed the impotant degree due to the parallel espreessway.

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 Shake table tests of a large model in 1g gravitational field were conducted to estimate deformation characteristic of asphalt pavement and effect of countermeasure by grid-type improvement with large grid spacing. As a result, when only the circumference of pavement was improved, and input earthquake motion became large, the amount of subsidence of pavement became large, but it was recognized that grid-type improvement with wide grid spacing has effect reducing the inclination on the surface of pavement. In the case that there were wide grid spacing ground improved walls around and right under the pavement, displacement difference causing pavement surface deformation occurred between improved walls and non-improved ground. It turned out that subsidence becomes large locally especially near the improved walls in the non-improved ground.

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 Construction of sheet pile walls(SPWs) behind existing quay walls was proposed as a countermeasure to prevent liquefaction-induced ground displacements. The shaking table tests under the centrifuge condition showed that SPWs were effective to reduce the displacements of liquefied ground and to protect the structures, such as storage tanks, against the ground displacements. Based on the experimental results, authors proposed a static model to estimate the external forces acting on the SPWs. In the proposed model, the displacement of the upper non-liquefied ground was input to the SPWs, while the earth pressure as well as pore-water pressure were applied from the both sides of the walls. The deformations and the stresses obtained by the model were well estimated the results from the experiments.

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 Strong ground motion prediction methods using fault model such as empirical Green's function method and stochastic Green's function method overestimate high-frequency strong ground motion on the soft soil deposit. We have already proposed a method that combines non-linear earthquake response analysis with empirical Green's function method. Here, we developed a simple procedure to evaluate response spectrum from the nonlinear site effect using AVS30 of the corresponding site and synthesized response spectrum by the empirical Green's function method. This proposed method has been verified by reproducing recordings with nonlinear response characteristics.

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 In this research, new remote assessment system for building damage assessment was developed and conducted operation test. The prototype system of remote building damage assessment system was developed based on the data of damaged houses due to the 2011 off the Pacific coast of Tohoku Earthquake, and conducted operation test for local government staffs which experienced building damage assessment. As a result of operation test and questionnaire survey, it become clear that building damage suffered from earthquake can assess using developed system and this system has many advantage point than present procedures.

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 The purpose of this research is to make clear the physical characteristics of earthquake motion phase. Using stochastic characteristic of group delay time calculated from observed earthquake motions we developed stochastic simulation models of earthquake motion phase spectrum. Taking into account the fact that the phase characteristic is controlled by fault rupture process and the randomness of wave propagation medium we introduce the Hurst index to evaluate these characteristics based on the fractal theory. Using not only observed earthquake motions but also the simulation results of shear phenomena of particle assembled mediums as well as experimental results of ultrasonic wave propagation in grass bead embedded mortar specimens we confirm the efficiency of proposed method to grasp the fractal characteristic of earthquake motion phase. To simulate earthquake motion phase we introduce the concept of fractional Brownian process (FBP). A simple method is proposed to determine the Hurst index and the variance of a given process characterized by the FBP. We find that the phase characteristic of earthquake motion can be expressed by this process which is a non-stationery function of the circular frequency. Using several observed earthquake motion we demonstrate this fact and show the efficiency of newly founded result to simulate realistic earthquake motion phase.

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 We examine a based pole method to give a gravel drain (the rubble backfill method of construction of the root case part) as measures to subsidence and the slant damage of the utility pole by liquefaction, and inspected the effect by a model experiment, in this study. We clarified that small construction method to take in the root case part of the pole have an effect on to delay the liquefaction around the pole or to control subsidence and aslant by the ground support power in crease.

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 The structure of a caisson breakwater has been necessary to have registance against Tsunami. For the verification of the designing of caisson, SPH-DEM simulation is hoped to play a critical role as a numerical method used instead of hydraulic experiment. As a numerical method, we develop two models for interaction between SPH and DEM. One is non-permeable model that is for impermeable structures to water such as caisson. The other one is permeable model that is for permeable structures to water such as riprap mound. To apply this numerical method to large-scale 3D model, the high performance computing is necessary for SPH-DEM simulation. In this research, the computational speed is improved by parallelizing the simulation code using GPU. This simulation is applied to Tsunami overflow analysis, and the applicability of the simulation method is validated by comparing to the experimental result.

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 Aseismic design method of residential fill slope concerns only the safety factor, residual displacement, and travelling distance; however, the estimation of the range of slope failures is necessary to make a safety regulations for construction of residential houses close to a slope. Based on slope stability analysis for 7 case histories in the past large scale earthquakes, the range of slope failures due to the earthquakes were investigated. The results were summarized as a rational evaluation for the range of slope failures considering not only first slip but also secondly one. The summarized evaluation and related discussion will be useful in future study of seismic performance of residential fill slope.

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 Assessment of the seismic performance of long span bridges is of great concern in ensuring seismic safety of those infrastructures against strong seismic events. However, this task involves great difficulties due to the complicated nature of the dynamic behavior of the structural system and components of the long span bridges, and sequences of multiple failure events of different kinds can take place for the case of a long span bridge. In this paper, a seismic performance assessment method for long span bridges is investigated, based on the evalutation of failure and damage sequences that take place under strong seismic ground motions using the incremental dynamic analysis (IDA) procedure. The specific amplitude of the earthquake ground motion that causes the damage in each possible failure mode is determined by IDA, and the failure sequence is obtained by relating the intensity of ground motion and the structural failures. Application of the procedure to a hypothetical steel V-leg rahmen bridge is shown.
 For long span bridges, strengthening of a specific member or component in the structural system may result in unexpected damage or failure at different locations in the event of strong earthquakes. It is clearly demonstrated that the IDA assessment procedure is useful in identifying such effects. The result of IDA using nonlinear time history analysis shows that the cover plate retrofit is effective in reducing the maximum strain in the girder, while it tends to increase the middle pivot bearing force and the strain in the V-leg sections.

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 In Nankodai, a residential area in Sendai City, serious damage was caused by the 1978 off Miyagi Prefecture Earthquake (M_J7.4) and the 2011 off the Pacific coast of Tohoku Earthquake (M_W9.0). To better understand the mechanism of the damage, it is necessary to have a better understanding on the seismic response of the residential area during the 1978 and 2011 events with high accuracy by taking into account site effects. In this study, we evaluated the seismic waveforms at the damaged area based on moderate earthquake observation records with very high density. Furthermore, based on the estimated waveforms, we discussed the characteristics of ground motion which influenced the seismic damage of the residential area. The estimated waveforms and findings will be useful in future study of seismic performance of residential areas.

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 In Tate New Town, a residential area in Ichinoseki City, fill slope was damaged by the 2011 off the Pacific coast of Tohoku Earthquake (M_W9.0), while it was not damaged by the 2008 Iwate-Miyagi Inland Earthquake (M_J7.2). To better understand the mechanism of the damage, it is necessary to have a better understanding on the seismic response of the fill slope during not only the 2011 event but also the 2008 event with high accuracy by taking into account site effects. In this study, we evaluated the seismic waveforms in the residential area based on moderate earthquake observation records. Furthermore, based on the estimated waveforms, we discussed the threshold ground motion which influences the seismic damages of the residential fill slope. The estimated waveforms and related discussion will be useful in future study of seismic performance of fill slope.

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 A continuous earthquake-tsunami response analysis was conducted in order to simulate process of damage to Shin Kitakami River Dyke, Ishinomaki City, Miyagi Prefecture, during the 2011 off the Pacific coast of Tohoku Earthquake. First, earthquake response analyses were carried out using the main shock ground motion at the site estimated from microtremor H/V spectra. Based on the residual deformation condition, tsunami response analyses were then conducted assuming the seismic damage remained. The result of the continuous analysis coincides with the actual damage to the river dyke. The importance of seismic assessment of river dyke as a procedure against tsunami disaster was specified.

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 This study developed a driving simulator with a tsunami inundation scenario to perform a series of experiments on evacuation by automobile drivers. To achieve the objective, the authors performed numerical simulation of tsunami propagation and the results were visualized from the view of a driver using 3D computer graphics (CG). The CG was installed to a driving simulator, which consists of three LCDs, steering wheel, and brake and accelerator pedals. 10 examinees were employed for the driving simulator experiment, and a future plan for the experiments is proposed based on the experimental results.

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 In seismic retrofit design of an existing multi-span continuous bridge, it is one way that horizontal inertia force of a superstructure can be distributed to a column with a movable bearing support by installing stoppers at the column top in order to reduce inertia force induced into a column with a fixed bearing support. To investigate dynamic response and develop a design method for bridges of which inertia force is distributed by mean of stoppers, a series of nonlinear dynamic response analyses was conducted.
 Because stoppers are generally installed at the column top with a certain gap between the superstructure and the bridge column, impact force is induced to the superstructure and the column when the gap is closed during earthquake excitation. In the analyses, modeling of impact spring of stoppers, amount of gap, the effect of shock absorbers are considered as parameters. It is found from the analyses that large impact force, which is eight times larger than flexural strength of the column, is obtained if no shock absorber is considered, and it is effective to provide a shock absorber that has relatively large initial stiffness in order to mitigate this impact force.

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 Open-type quaywall with sheet pile wall anchored by forward batter piles, which is constructed with an open-type wharf built in front of sheet pile wall, is used for not only newly built structures but also reformation. Reliability-based design has been adopted in the 2007 edition of technical standards for port and harbor facilities. However, the design method of this type is not specified. Therefore, we examined its seismic coefficients and partial factors for level-1 earthquake ground motion. We have found that the performance requirement for sheet pile quaywall and open type quaywall are satisfied by following method: 1) seismic coefficient of sheet pile wall part shall be calculated by the equation for sheet pile wall with vertical pile anchorage, 2) piled pier part including sheet pile wall shall be designed by frame analysis using partial factors for open-type quaywall on vertical piles.

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 Uplifting Slide Shoe (so called UPSS) is a slide bearing consisting of a horizontal plane and two inclined planes. The restoring force of UPSS is caused by the gravitational potential energy. The original time-history characteristics are uniquely determined by the slope angle.
 In this paper, the predominant period of UPSS is evaluated in comparison with rubber bearings and isolation bearings. One method is utilizing the natural period based on the maximum displacement and the associated restoring force. Others are Fourier transform and wavelet transform. As a result, the predominant periods obtained by Fourier transform and Wavelet transform spread over a wide range of period, and those are almost consistent. Furthermore, by comparing the time history response results, the change of the predominant period along the time axis has become clear in the wavelet transform result.

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 According to monotonic horizontal loading tests of the flexible reinforced concrete (RC) pier model specimen, the failure characteristics do not follow the former shear failure or flexure failure, but it is between the two failures. To evaluate the restoring force characteristics of the flexible RC pier, the cyclic loading tests under axial force should be conducted.
 In this study, the cyclic loading tests under axial force was performed, which were compared with monotonic horizontal loading tests. The influence of axial force and cyclic loading to restoring force characteristics was evaluated together with the reinforce effect of transverse reinforcement. In the meanwhile, the factors of elongation of axial reinforcement greatly affecting deformation capacities was discuessed.

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 This study aims to develop disaster management system for governmental stakeholders to design and implement an effective disaster responses. In this paper, as for the first step of total this research, the disaster related budget of Yabuki town in Fukushima prefecture is analyzed.
 As a result, in the parts of risk management, the budget is mainly used for implementing the effective responses during emergency phase. This can be desctibed that the parts of the budget for the directly reducing the damages are comparatively small.
 On the other hand, it is difficult to evaluate the effectiveness and necessity of each countermeasures by only focusing on the use of the budget shown in this paper.
 To achieve our purpose, it is necessary to develop the ROI (Return On Investment) model in the disaster management field.

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 When an airport facilities, such as a runway and a taxi way, are dameged by an great earthquake, it is assumed that bearing capacity of soil layer below asphalt pavement will decrease with increase in excess pore water pressure and reduction of effective stress. If an airplane runs in such a situation, it is worried that the function of runway will be lost due to remarkable deformation such as differential subsidence caused by a load of airplane. In this study, numerical analysis, intended for the past shaking test of asphalt-liquefiable soil layer model to estimate bearing capasity bafore and after liquefaction, was carried out in process of dissipation of excess pore water pressure. As a results, a series of numerical analysis showed that the reqired performance of asphalt pavement was obtained only by slight recovery of the elastic coefficient in the liquefied soil layer directly with a dissipation of excess pore water pressure ratio.

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 This paper describes seismic systems on continuous structure of the floor framing girders in the existing suspension bridge.
 In order to solve the problem of fatigue damage due to the increase of the over-loaded traffic or the damage caused by the water leakage from the expansion joints in floor framing girders of the existing suspension bridge, the application of bearings with the good slide and rotational function in floor framing girders is effective. Movable bearings are installed in the floor framing girders in order to release the constraint at fix supports and as a result, it is expected that the floor framing girders with deck slab and the stiffening truss girders perform independently and the main towers and anchorages support the inertial force through the seismic dampers. Furthermore, elastic restrained cables are installed between the end of floor framing girders and main towers, anchorages to improve the performance of the bridge against the service load and seismic load.

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 In simulating strong earthquake motions for design purposes, “spectral fitting method” is commonly used with assuming randomly distributed phase content. However, it is not quite clear how large the ground response could vary under those simulated earthquake motions with random phase. This paper examines maximum response of 1 dimensional nonlinear uniform ground when it is accelerated by simulated earthquake motions with random phase. To check nonlinear response of ground, equivalent linear analysis and non-linear direct integral analysis with Ramberg-Osgood model are conducted. Through series of calcultions, it appeared that coefficient of variation of maximum ground response which has a certain nonlinearlity, that is, acceleration, velocity and displacement, are all approximately 0.1-0.2 and mostly less than 0.2.

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 To prevent the stone wall structure from collapsing by an earthquake, it is indispensable to grasp the anti-seismic performance and enforce the wall by retrofitting if necessary. In this study, the authors has conducted an analysis of seismic response of historic stone wall structure and examined the retrofitting method based on the Two-dimensional Extended Distinct Element Method.
 As a result, the anchor-reinforcement method was selected as an anti-seismic reinforcement, for its minimum intervention and visual impact to the historical stone wall. By comparing the movement of the wall with or without anchor reinforcement and recognizing the pattern by various applications, the study indicated the necessity of anti-seismic reinforcement as well as the tendency of response behavioral change and examined the validity of anchor reinforcement.

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 Effective stress analyses were conducted in order to know effect of input earthquakes and shape of liquefaction strength curves on soil liquefaction. As a result, it was found that long duration earthquakes may bring on severe soil liquefaction in consequence of amplification of earthquake motion through subsurface layer even though its amplitude at base is small, and soil liquefaction due to such long duration earthquakes with low acceleration is largely affected by liquefaction strength for a large number of loading cycles. Results revealed that both response of subsurface layer and liquefaction strength for a large number of loading cycles should be accurately considered in assessment for soil liquefaction potential against long duration earthquakes.

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 Many earthquake records are observed by the super-dense realtime monitoring system, SUPREME, by Tokyo Gas Co., Ltd. Amplification factors are estimated for over 3, 000 sites using observed recors for about ten years. Observed SI values were gathered for the five minutes and the distribution map of SI values with 50m-meshes were calculated after ten minutes at the 2011 off the Pacific coast of Tohoku earthquake. Average amplification factors of SI values at observation sites are estimated by attenuation curves of observed earthquekes with K-NET records. Those show to be well correlated to average S-wave velocity in the upper 20m (AVS20) and geomorphologic classification.

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 As a design earthquake to check the seismic safety of a railway structure, the standard response spectrum of L2 earthquakes is generally used. In contrast, in the site which is located near large-scale source regions and/or where an earthquake motion is assumed to be significantly amplified, special care is required on the seismic design and L2 earthquake motions must be evaluated by site-specific prediction methods of strong ground motions. However, there has been a problem that clear indices for judging the magnitude of earthquake amplification do not exist. In this research, we have examined a technique to extract the points where earthquake motions are assumed to be significantly amplified by using high-density earthquake observation records in recent years and evaluation results of the amplification characteristics of earthquakes at seismic stations across the country. The validity of the proposed method is confirmed by applying the method to the past earthquake records. By using the proposed method, the site requiring special attention can be easily extracted considering the amplification characteristics on every site.

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 Considering high uncertainty of earthquake motions, an insensitive structural system for the loss of its functionality is a good system. In this paper, the methodologies for the insensitive structural system are summarized. And as the application by the structural design, the response of structural system with inhomogeneous dynamic propertie is evaluated based on radom vibration theory. As the results, maximum response level and the coefficient of variance of maximum response under high uncertainty of earthquake motions can be decreased and the inhomegeneous structural system can be an insensitive structure.

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 In Korea, the heightening the earth dams have been performed for securing the water resource and preventing the disasters such as flood and drought. In addition, the consideration on the safety of heightened earth dam is required as the frequency of earthquake increases in recent years. Therefore, this study was carried out on analyses on the seepage flow and the dynamic response induced by both the sinusoidal wave and earthquake motions as for the 4 kinds of changing the volume of the added core, and the influence on the seepage flow and the dynamic shear stress was discussed. As the results, the seepage line becomes lower and the shear stress, especially in the added core can be reduced, and it can be indicate that the seismic performance of heightened earth dam can be improved.

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 Serious damage occurred at RC rigid frame viaduct sites of Tohoku Shinkansen in Esashi Ward, Oshu City, during the 2003 Southern Sanriku Earthquake (M_J7.1). In order to analyze the damage mechanism, it is important to evaluate strong ground motions at the viaduct sites with high accuracy, taking into account site effects. In this study, temporary seismic observation with very high density was conducted along the viaduct sites. Moreover, seismic waveforms along the viaduct were estimated based on the asperity model considering empirical site amplification and phase effects. The estimated ground motions will be useful in the detailed study of the damage mechanism.

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