Recently, a lot of earthquakes occurred in Japan. Damage has expanded because the risk acknowledgment to the earthquake is insufficient. It began to work on the individual disaster prevention activity in a lot of regions. However, there is a big individual variation at the risk acknowledgment level in the region. This individual variation is an evil of the activity. In this study,the questionnaire is done partially of the risk management research on the regional disaster prevention advancement to the earthquake tsunami disaster in the Wajima City harbourfront area that experiences the earthquake of recent years. In this study, the workshop intended for the resident around the Wajima City harbourfront area that experiences the Noto Hanto Earthquake of 2007 is executed. And, the insufficiency of the vulnerability in the region and the risk acknowledgment between regions is arranged. It aims at the conducting research of the possibility of the regional disaster prevention power improvement in doing a risk communication interactive the administration to the local populace.

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 The telecommunication conduits are needed to protect underground cables from damages due to earthquakes.However, the seismic capacity is being degraded due to the superannuated conduits that were constructed during the high-growth economic period.To sustain the reliability of the conduits efficiently through maintenance is the current challenge.
 This paper presents the reproductive experiments of the damage of underground telecommunication cable at the time of earthquakes in order to clarify the limit of opticalfiber cable restoration. By modeling the seismic damage of undeground conduits for the experiment, we could confirm that optical fiber cables are damaged not only at conduit fractures but also manholes which they are pulled into. When the characteristics of optical fiber cables on the seismic disaster were verified by experiment, it is shown that not only tension force but also bending angles causes the fault of transmission. The relation between the tension and the bending angles that the cable suffers damage is clarified. This result can be used for the rational measures to prevent the damage of the telcommunication service.

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 Gravity anomaly is one of efficient methods to evaluate underground structure, which is essential for estimation of ground motion due to earthquakes. Data observation is, however, costly since it requires expensive devices. In order to overcome this problem, Morikawa et al. have been working to develop a mobile gravimeter that uses force-balance (FB) accelerometer. In comparison to the conventional spring type gravimeters, it is less costly, compact and can be carried by relatively small carriers. However, it raised problems that the observed data are severely contaminated by various kinds of disturbances such as engine vibration and carrier motion. Therefore an appropriate data processing method for extracting gravity anomaly signal from such observed data is required.
 For that purpose, we propose to use the statistical independence property of gravity anomaly and other noisy data. The gravity anomaly and other noises are generated from different sources and it can be safely assumed that they are independent.
 As a scheme of considering independence of signals, blind source separation techniques are used. Second Order Blind Identification method (SOBI) separates the target sources by assuming that source and noises are un-correlated at various time-lags. Similarly, Independent Component Analysis (ICA) separates the sources by maximizing the independence of linearly transformed observed signals. It is proposed to use one of ICA-based algorithms, ThinICA, that implements the maximization of independence among source signals at various time-lags and thus incorporates the advantages of both SOBI and ICA.
 The proposed method is applied to the data observed at Toyama Bay, Japan. It is observed that the motion of carrier (ship) influences the performance of de-noising algorithm. Under certain favorable data acquisition environment, the proposed method was able to salvage the gravity anomaly data from the noise-contaminated data with the accuracy sufficient for the purpose of identification of gravity anomaly distribution.

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 The 2011 great east Japan earthquake tsunami hit the east coast of Japan and caused serious damage. The tsunami caused large-scale erosion and scour, resulting in the destruction of many coastal structures. Especially, the tsunami over- and back-flow caused the scour around the coastal structures. Therefore, research on prediction models of the topography change by tsunami is important. In this paper, the scour survey carried out in Miyagi and Fukushima prefectures after the 2011 great east Japan earthquake tsunami is reported. Moreover, prediction models which can evaluate the scour around the structures are proposed. Next, we applied the H2D numerical model which can evaluate bed-load and suspended-load sediment transport to Kesennuma Bay, Miyagi in connection with the observations collected after tsunamis, and we confirmed the reproducibility of the model by adjustment of the bed load coefficient.

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 Recently, application of rubber bearing to multi-span continuous bridge became popular. But this design caused the increasing size of expansion joint, problem operation and maintenance. Therefore, Up-lifting Slide Shoe (UPSS) has been proposed to deal with the thermal expansion and contraction of bridggiders. This paper presents the result of dynamic response analysis of multi-span continuous bridges witrubber bearing and UPSS considering the effect of statically indeterminate force by nodal force at thboth ends of a girder. As the result, it was cleared that UPSS has the effective of response suppressiomore than rubber bearing.

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 Many concrete arch dams passed nearly 50 years after construction. Because of growing public concern with stability at the time of a large earthquake, it is necessary to more rational seismic performance verification. Although model considering the bedrock is made in seismic performance verification, what it becomes difficult to extract natural modes of the dam body in case of considering the mass of the bedrock has been pointed out. And when carrying out seismic response analysis of civil engineer-ing structures built on bedrock spreading in semi-infinite like arch dam, we must set the appropriate boundary conditions be-tween analysis domain and free field. From the above, in this study, we have examined how to give the mass of rock when carrying out eigenvalue analysis and how to give boundary conditions to reproduce the actual phenomenon accurately when carrying out seismic response analysis.

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 Recently, the seismic retrofitting method using damper devices increases. Two types of seismic damper are often used, one is the hysteresis damper and the other is viscous damper, and each damper has different characteristics. Generally the hysteresis damper is cheaper than viscous damper. But the performance of the viscous damper to follow the girder elongation and shrinkage caused by temperature change is relatively low. It is necessary to design two types of the optimal damper. The purpose of this paper is to propose a rational seismic design method for the seismic retrofit of existing bridges. Damper capacity considering combination was estimated using single degree of freedom system. Dynamic response analysis of total system model was conducted. It was confirmed that the proposed design method was effective for reinforcement of highway bridges.

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 Since earthquake resistance performance required for a dam during large-scale earthquakes is to ensure reservoir functions, a spillway gate is important associated facility to satisfy the earthquake resistance performance. However less actual observation records on dynamic behavior of the gates during earthquakes than those of dams has been collected before, therefore the behavior enough for evaluation of the earthquake resistance performance of the gates are not identified.
 Based on such background, in this research, the vibration tests and the earthquake observations for gates of a concrete gravity dam, which aim to obtain basic information on the dynamic behavior of the gates during earthquakes, were implemented. And then, the eigenvalue analysis by using the three-dimensional FEM Model and the simulation of the earthquake observation records were implemented, and the analysis model to be applicable for the evaluation of the earthquake resistance performance of the gates was developed based on the results of the simulation.

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 UPSS (Uplifting Slide Shoe) is a kind of sliding bearing which is combined with a horizontal plane and inclined planes on both sides. The seismic energy is dissipated by the sliding friction, the structural damping and the hysreresis energy dissiation of the pier. In this paper, influence of the inclined angle, the friction coefficient of UPSS and the yielding load of the pier to the seismic behavior is investigated. As a result, it is confirmed that there is a trade-off relationship between the displacement of UPSS and the response ductility factor of the pier. Namely, it is observed that the larger the inclined angle, the shorter the UPSS displacement and the greater the absorved energy of the pier. The reason is that the seismic behavior changes heavily depending on the response period for each ground type. This finding can be used to design appropriate UPSS configration based on the target seismic behavior.

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 The huge tsunami caused by the Great Tohoku Earthquake devastated the coastal area on March 11, 2011. It is important to review disaster prevention and reduction of the coastal regions. In this study, 3D tsunami simulation by a SPH method, which is one of the meshless particle analysis, is developed to accurately estimate tsunami inundate zone and to assess the fluid force acting on coastal structures. In addition, a high resolution geography modeling technique for particle simulation has been proposed. The modeling technique converts from randomly distributed point group data given by aerial survey and bathymetry to particle simulation model. Finally, efficiency and adequacy of the proposed simulation technique has been validated through an application to one of the harbor city Taro in Iwate prefecture.

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 Fiber reinforced polymer (FRP) has become a popular material in the past few decades. It has been extensively used for strengthening and retrofitting of concrete structures. High strength to weight ratio, high initial stiffness, linear elastic behavior and ease in application has made it material of good choice for the seismic retrofitting and strengthening of masonry structure. There are many guidelines proposed by many researchers to determine the amount of FRP based upon the seismic base shear requirements. But, there is no theoretical, numerical and experimental researches to determine the optimum placement and quantity of FRP to reduce the cost of retrofitting.
 In this research, an attempt has been made in order to find the optimum quantity and placement of FRP for strengthening brick masonry wall system. Required objectives are achieved by performing diagonal compression test on ten masonry wallets. Masonry wallets were carrying different volume and arrangement of FRP strips. Response of masonry wallets with different volume and configuration of FRP strips are recorded using a digital acquisition system. Experimental results are carefully analyzed in order to propose an optimum and efficient retrofitting procedure of masonry wallets with FRP. Experimental results shows that correct retrofitting scheme can not only increase the efficiency but can also reduce the retrofitting cost and effort.

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 Since seismic motion of a building incorporates shape effect if the building has anisotropic shape, we should treat such shape effect for seismic response simulation of furniture. Owing to recent progress of computer devices, finite element seismic simulation of building enables us to extract particle motions at arbitrary locations in the building. The particle motion in the building is regarded as a rational input for seismic simulation of furniture in terms of integration of the shape effect. Firstly, we modeled a building having anisotropic shape, then investigated a direction of strong seismic motion by means of a lot of finite element simulations with white noise input. Finally, we performed a sesmic simulation of furniture with rational input produced by the finite element seismic simulation for the building. The seismic response of furniture naturally reflects the direction that indicates the intense seismic motion of the building and the simulation results are in good agreement with those measured by actual surveys concerning the striations caused by the earthquake.

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 The finite element analysis is hardly applicable to simulation of slope failure because of insufficiency of handling large deformation. The smoothed particle hydrodynamics (SPH) which is known as a powerful simulation tool for large deformation problem is applied to the earthquake induced slope failures simulation. Firstly, a new SPH form of the equation of motion which improves an accuracy of earthquake response analysis is proposed. Secondly, the Rayleigh damping is introduced to the SPH simulation successfully. Thirdly, it is shown that the process of development of a failure line is affected by the SPH particle density and the Rayleigh damping.

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 In this paper, we propose the method to evaluate the failure probability under seismic motion of the structure considering multiple failure modes. In proposed method, the failure probability evaluation factor is unified, and it is possible to find the failure probability by integration of one parameter. In the calculation result, it is verified that the failure probability by proposed method is greater than the failure probability of each failure mode, and less than the sum event probability assumed that each failure mode is stochastically independent.

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 Intense liquefaction occurred during the 2011 off the pacific coast of Tohoku earthquake at reclaimed land along the Tokyo bay area. Shinkiba area was one of the liquefied areas, but liquefied area and non-liquefied area were divided clearly. Downhole array earthquake observation was carried out in this area. The liquefaction was not found at the observation station, but the distance to the nearest liquefied site was approximately 120m. It was supposed that the difference in liquefaction condition of both two sites is caused by difference in liquefaction strength of surface layer. We estimated liquefaction strength of the surface layer of the liquefaction point by effective stress analysis. As a result, the liquefaction strength was estimated to be around R_L20=0.18. In addition, as for the liquefaction strength, a little lower possibility was suggested.

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 The ICSS (seismic Isolation Controlled Slide System) is a structural system for effective seismic design of multi-span continuous girder bridges based on the idea of an optimized combination of isolation bearings, seismic dampers and slide bearings. It is observed that ICSS tends to be sensitive to the input incident angle, partly due to the particular nature of the seismic dampers that act as energy dissipation device only in the axial direction. In order to achieve designated seismic performance a bridge with ICSS, it is of great importance to correctly evaluate the seismic response of the system under realistic ground motions. For this aim, seismic response assessment of a bridge with ICSS using bi-directional seismic ground motion inputs is performed. The bi-directional accelerograms are generated so that the bi-axial response spectrum is compatible to the design spectrum specified in the Japanese bridge design code. It is found that the rotational direction of the trajectory of the bi-directional acceleration input due to the inter-component phase difference, classified as 'clockwise input' or 'counter-clockwise input' directions, significantly influences the response of ICSS.

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 We develop a system to perform structural response analysis of large number of structures considering local soil properties by combining soil amplification analysis and structural response analysis programs. Here, we convert urban data stored in the geographic information system to input city models for each simulation, and use output waves computed by soil amplification analysis for input of structural response analysis. The soil and structural response analysis programs are enhanced with high performance computing for application to large areas. By using such a system on high performance computers, we can simulate large areas with more than 10⁵ structures or simulate multiple cases with different input ground motion, soil structure, or structural properties in a short time.

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 We are focusing on dense urban areas where many vacant houses exist inside Kanazawa up as object areas of this research, and a questionnaire survey for the residents outside those areas was carried out. By analyzing the result, we investigated possibility of performing seismic retrofit in the case of a move to a vacant house in object areas. As the result of this study, we showed that it is effective to decide and promote candidates.

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 This study examines a relationship between average shear wave velocity in the upper 30m(AVS30) and seismic response of wooden house, in order to apply information of subsurface structure to an evaluation of a damage to wooden house. We evaluated shear wave velovites of subsurface and accelerarion at surface by ground response analysis based on equivalent linear method at a site of borehole in Maizuru City, Kyoto Prefecture. A relationship between response acceleration at surface evaluated by the ground response analysis and maximum drift angles of wooden house(R) was investigated. It was found that response acceleration in a short period range affects R when a base shear coefficient(C_y) of house becomes large. Finally, it is clarified that AVS30 correlates to R in case of 0.1 and 0.3 in C_y.

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 This study focuses on the water-supply pipeline damage in northwestern Miyagi Prefecture, where the seismic ground motion is predominant cause rather than tsunami and liquefaction. The information on damage to water pipeline was collected from 5 cities and towns; Osaki, Misato, Matsushima, Kurihara and Shiogama. The pipeline damage information was compiled in the GIS. Fragility due to pipe diameter and pipe material was confirmed to be similar as one in the previous study. Especially the fragility of small diameter vinyl pipeline which is commonly used in the rural area is useful for damage estimation in the future.

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 Earthquake and ambient vibration monitoring of the crest of an aged arch dam was carried out. Long-term continuous monitoring was conducted to determine the change in natural frequency over time by installing accelerometers at two locations on the crest. On the other hand, short-term ambient vibration monitoring was also conducted to evaluate the dynamic characteristics of the entire arch dam system, such as the natural frequencies, modal dampings and mode shapes, by installing an array of sensors. This paper presents the Young's modulus of the dam body concrete and foundational bedrock with a small amplitude, based on data from the short-term monitoring, as well as three-dimensional finite element analysis. The results would enable further investigation of the relationship among the natural frequency, reservoir level and body temperature of the dam based on data from the long-term monitoring as a bench mark.

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 Relation between splay fault slip and shallow subduntion plate boundary fault slip have not studied enough. In this study, we consider dinamically the difference between the ruputuring process of splay fault and the rupture process of shallow subduction plate boundary fault when fault rupture propagates from deep area to shallow area of the plate boundary. Also, we consider it in the view point of characteristics of generated tsunami.

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 During 2011 Tohoku-oki earthquake, strong ground motion caused serious damage to residences at Furukawa area in Miyagi Prefecture, north eastern part of Japan. Based on the damage distribution, severe damages were concentrated in southern part of Furukawa district. The variation of damage distribution implies that the ground motion characteristics were not uniform in Furukawa district. In this study, we started to install the very dense seismic-array and observe ground motion. We assumed one-dimentional horizontally-layered structure just under the staions and estimated ground structure by using the records based on the observation. Then, we calculated velocity waveforms of the earthquake on January 1^st 2012, by using the model. However, the waveforms do not agree well for the following phases, and this implies that one-dimentional horizontally-layered structure is not enough assumption to simulate the ground motion in Furukawa district.

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 Assessment of earthquake damage is expected to be improved by appropriate setting of the scenario fault rupture. Estimation of interplate coupling, using large-scale analyses of the observed crustal deformation data based on detailed data of crustal structure, could be one way to improve it. However, it has not been achieved because of the difficulty of generating high-fidelity numerical models of crustal structure for numerical analyses and the computational cost. In this research, by using the techniques of high performance computing, we developed a method for generating a high-fidelity three-dimensional crustal structure finite element model, and a method for crustal deformation analysis using the generated model. The crustal deformation analyses in Southwest Japan show the significant difference between the results of our method and conventional method. These analyses indicate that there is a significant difference in estimation results of interplate coupling, if high-fidelity models as shown in this paper are not used.

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 Estimation of dynamic characteristics of subsurface of ground such as predominant period, amplification factor, shear wave velocity play an important role in researchs of the effects of long-period ground motion earthquakes on high-rise buildings in big cities. Microtremor observations in Hanoi and HoChiMinh cities of Vietnam were conducted and the predominant period of the ground at the sites could be estimated from the horizontal to vertical (H/V) spectral ratios of microtremors by using the Nakamura method. The obtained results show that the grounds of the mentioned two cities have considerable possibility of resonance with long-period ground motions. Then, the spectral accelerations in bedrock of Hanoi and HoChiMinh cities were estimated by attenuation relationship of Uchiyama and Midorikawa 2006 with the far-source rupture faults. Next, the accelerations on ground surface of the above two Vietnamese cities were estimated by using spectral ratio of microtremor and inverse Fourier transform. Finally, the time history analysis was conducted for 8 high-rise buildings in Hanoi and HoChiMinh cities by using the obtained accelerations. The results of the final step show that far-source rupture faults have considerable possibility to generate long-period ground motions that cause certain large behaviors of high-rise buildings in the Vietnamese cities.

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 This paper describes the damage to RC rigid frame viaducts caused by the 2011 off the Pacific coast of Tohoku Earthquake. Observations were made to investigate the severity of the damage to RC viaducts and the mechanism of the damage. And, authors conducted the static non-linear analysis based on push-over analysis, by taking into consideration that the ductility of columns can be evaluated by response acceleration in case of elastic behavior.
 As a result of observations, we found that the seismic damage caused to RC viaduct columns was mainly located in the vicinity of the upper edge of columns. And, the results of numerical analysis indicated that the damaged RC columns received the seismic action upto 1120 gal in the cross section of rigid frame.

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 During the 2011 off the Pacific coast of Tohoku Earthquake, many residents which inhabit coastal area used the car/ on foot for evacuation from mega tsunami. But huge number of residents can not reach for the evacuation space safely. The reson of that situation is that traffic congestions occurred in the evacuation route for going forward evacuation site due to the trouble of traffic signal and rapid increase of traffic demand on the road, and on foot evacuation people do not recognize the correct evacuation route and evacuation center. This paper analyzes the evacuation behavior of resident who suffered from The 2011 off the Pacific coast of Tohoku Earthquake in Kesennuma city using language analysis. It comfirmed that recognition of evacuation from tsunami is different from each evacuation methods.

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 It has been shown based on previous research that damage of RC bridge columns can be mitigated and ductility capacity can be enhanced by implementing polypropylene fiber-reinforced cement composites (PFRC) at the plastic hinge. The bridging action of polypropylene fibers which can mitigate crack propagation and widening of cracks has similar action with the lateral confinement by tie bars. Thus, it is likely that use of PFRC can reduce amount of tie bars required for ductility capacity enhancement. This paper shows a feasibility study for reducing an amount of tie bars by implementing PFRC at the plastic hinge. Based on a hybrid loading experiment and a nonlinear dynamic response analysis, it is shown that it is feasible to reduce an amount of tie bars by half by using PFRC though failure of the column slightly increases.

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 In this study, we constructed a 3D subsurface structure model for ground motion simulation in the Tottori plain. Therefore, we set common physical properties (ρ, V_P, V_S) for sedimentary layers in the target area and thickness of each sedimentary layer is estimated through inversion analysis from observed phase velocity data at the microtremor array observation sites. Depth estimation of seismic basement is supported by gravity anomaly data under an assumption of two-layered homogeneous medium. 3-D subsurface structure model is constructed from spatial interpolation of the layer boundary depths with 2-D 3rd-order B-spine function. Strong ground motions due to the 1943 Tottori earthquake (M7.2) is simulated by the 3-D finite difference method with the 3-D subsurface structure model. The model was well verified by comparing the distribution of peak ground velocity with the damage distribution under the 1943 Tottori earthquake.

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 It is always an argument whether we can predict failure mode and hysteretic behavior of a prototype structure based on a scaled model. In this study, effect of maximum aggregate size, evaluation of rebar section area and difference of reinforcing bar strength on the seismic performance of reinforced concrete bridge columns was investigated based on a response loading for a 5/36 scaled model (S-4 column) of a full scale column (C1-5 column). It is shown that progress of failure of core concrete is less significant in a scaled model than C1-5 column. It is also shown that the scaled model column S-4 provide about 7% higher moment capacity than C1-5 column because of the smaller progress of failure in the scaled model column.

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 Under an extreme ground motion, the flexural capacity of a RC column deteriorates due to crushing of core concrete and buckling of longitudinal bars. Thus, it is important to prevent damage at the plastic hinge region for developing "damage free" columns which are free from repair even after an extreme earthquake. For this purpose, a column which uses ultra high strength fiber reinforced concrete segments at the plastic hinge region is proposed. The seismic performance of the column is clarified based on a hybrid loading experiment. It is shown that the proposed UFC column exhibits a good performance for a damage free column.

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 The purpose of this research is to build the spatiotemporal model for appropriate or necessary disaster responses. This paper proposes the running spectrum technique of text data to analyze the change or trend in the disaster management cycle as a first approache of final goal of this research. The news reported by Fukushima- Minpo newspaper is used for the verification of the technique. The result can show the dynamic characteristics of the data that change in time domain. As time goes on, more digital data/information in addition to Tohoku disaster can be available. Then, the proposed technique will be more efficient and effective to analyze huge digital information for appropriate understanding of the process of the events and occurrences.

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 The authors have discussed the validity of fault models of the 1946 Showa-Nankai Earthquake based on acutual accounts of people who experienced the earthquake. One problem, which is always evident, is the ambiguity of reported accounts. The 2011 Tohoku Earthquake, which was the same type of subduction-zone type earthquake as the Nankai Earthquake, gave a lot of accurate strong motion records as well as recent acutual accounts of people. Using this valuable information, our study attemps to verify the validity of using first-hand accouts to explain fault models of the Nankai Earthquake.

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 The occurrence of the 2011 Tohoku earthquake (M_w9.0) along the Japan Trench motivated us to hypothesize an equally gigantic earthquake along the Nankai Trough, which is another plate boundary close to the coast of Japan. The evaluation of strong ground motions for such an earthquake should be based on a source model whose applicability for gigantic earthquakes has been demonstrated using existing strong motion records including those from the Tohoku earthquake. In this article, strong ground motions for a scenario earthquake with M_w9.0 along the Nankai Trough are evaluated using a source model called the "SPGA model", which can reproduce strong ground motions from gigantic earthquakes quite accurately. Because it is difficult to predict the locations of SPGAs, many cases are considered with different distributions of the SPGAs. The result indicates that the ground motions are strongly dependent on the locations of the SPGAs. When an intense SPGA is close to the target site, the ground motions can be much more intense than those conventionally assumed for the design of infrastructures.

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 By the development of sewerage, the pipe extension has become 420,000 km and the sewage facility stock is increasing more. If it has passed years considerably since it constructed, the possibility of the road caving becomes higher. Incidents in FY 2009 was about 3,800 points. In particular, in recent years, the deterioration of the sewage pipe becomes significant. The immediate measures are urgent. The pipe rehabilitation by the non-open method is attracted by considering the impact of drilling and road traffic. But the pipe rehabilitation has been designed with a lot of methods, on the tube diameter of less than φ800mm, the self-reliance pipe method is mainly employed. Because the strength withstand the external pressure is needed for self-reliance pipe method, the thick becomes very large, and it is difficult to ensure workability and sections. In this study, considering the self-reliance pipe, it is verified by performing experiments and analysis.

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 This paper presents the development of a new numerical analysis method for failure of RC structures subjected to tsunami impact. The major developments are the implementation of failure analysis to a large scale solid finite element method and the coupling of tsunami analysis to the structure analysis. The failure analysis employs the particle discretization scheme to model most complicated crack configuration in concrete, and the tsunami analysis is based on the stabilized finite element method of solving the Navier-Stokes equation with free surface. OpenMP and MPI hybrid parallelization is implemented. An experiment of tsunami impact on an RC plate is reproduced, in order to examine the ability of the developed method.

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 In this paper, the authors reexamined the evaluation method, proposed previously by the authors, on the effect of opening of joints on soil constraint around a tunnel, first. Then, the authors reevaluated joint stiffness of actual tunnels and the influence of the use of such stiffness on earthquake response results of tunnels. Next, earthquake response analyses were conducted in consideration of stiffness degradation of tunnel lining due to cracking, and results of the earthquake response analyses were evaluated. Finally, based on such examinations, the authors summarized a new earthquake resistant design method, taking consideration of the features as follows. Reinforcing bars in the longitudinal direction should be arranged so that the tensile yield strength of reinforcing bars may become greater than the ensile strength of concrete lining, without over evaluating joint behavior, in the area where earthquake ground strain is not large, In the area where ground strain is large, on the contrary, average strain of tunnel lining should be reduced, by arranging joints in consideration of soil constraint around a tunnel.

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 We discuss evacuation planning from tsunami disasters in Kushiro City. The city has not experienced severe tsunami disasters since the recorded history of the 19th century. However, "Ainu", an aborigine of Hokkaido, has been brought down past severe tsunami disasters by word of mouth. In addition, geological evidences indicate them as well. The Hokkaido Prefectural Government announced new data and maps obtained by the tsunami simulation that is reconstructed on account of the geological evidences of the past huge tsunami disasters. We performed on-site investigation by using geographical survey, and used GIS analysis. Then, we concluded that survivability will increase without new evacuation buildings for tsunami disasters if we use tall buildings and elevated highways which have been used, as temporal evacuation sites.

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 A continuous earthquake-tsunami response analysis was conducted in order to simulate process of damage to a highway bridge of which superstructure and a pier (P3) were washed out by the tsunami of the 2011 off the Pacific coast of Tohoku earthquake. First, an earthquake response analysis was carried out using the mainshock ground motion at the site estimated from an aftershock record. The base of P3 was found to be possibly damaged by the seismic action. A tsunami response analysis was then conducted assuming the seismic damage remained. The tsunami action was found not only surpass the strength of bearings but shear strength of P3; the result coincides with the actual damage to the bridge.

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 Pacific-coastal areas of Tohoku region were totally swept by the devastating tsunamis triggered by the 2011 Great East Japan Earthquake. Almost all of some nineteen thousands victims were killed due to drowning in the tunamis. In order to clarify the actual situations of residential evacuation from tsunami risks anticipated after the quake, we collected 509 newspaper articles related to resident's tsunami evacuation and conducted content analysis on them. Focusing Iwate and Miyagi Prefectures, appropriate and inappropriate evacuation timing are statistically discussed from the viewpoint of difference between survivers and victims, and so on. Immediate evacuation is statistically confirmed to be only successful way to survive based on Iwate News Paper. We can say that evacuation leading requires some time control.

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 Performance of a low cost base isolation system using scrap tire rubber pad (STRP) for developing countries is investigated. In this paper, pyrolysis gas chromatography (Py-GC) to identify the material of STRP, lateral shear tests and finite element analysis to determine the deformation capacity are conducted. The Py-GC analysis show the main constituent of STRP rubber is natural rubber. In the shear loading tests, the STRP isolator specimen has a shear strain capacity of 100% when loaded with 5MPa axial pressure. The results of experimental test and FE analysis are generally consistent.

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 A stone construction like a lantern and a gravestone is a simple unstable structure which stacked stones. So the damage of a stone lantern caused by the earthquake has occurred mostly. It is necessary to take the prevention from a fall of a lantern into consideration because the fall of a lantern is very dangerous.
 In this study, we estimate the seismic performance of a stone lantern using 3-D DEM analysis and real scale shaking table test, and evaluate the seismic resistance of the reinforced lantern. As the result, the seismic performance of the stone lantern was able to be evaluated by the shaking table test and 3-D DEM analysis. It was able to evaluate that the reinforced lantern was effective against the earthquake motion by experiment. The proposal of the suitable reinforcement against the earthquake was estimated.

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 Car evacuation in Kesennuma city after the 2011 off the Pacific coast of Tohoku Earthquake was focused on in this study. Authors interviewed local government officials to obtain the information regarding road situation during the Mega Tsunami struck the city. Traffic simulation system was built and the stochastic user equilibrium model was applied to demonstrate traffic flow of the evacuating vehicles. As the result of the simulation, it was shown that the number of the evacuating vehicles was roughly estimated and that the road situation after the earthquake was reproduced.

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 The goal of this study is to estimate source and path attenuation parameters of recorded earthquakes in Tehran province, Iran so they can be used for strong motion prediction purposes. For this, we have used four well recorded earthquakes recorded on Iran Strong Motion Network (ISMN). Assuming a simple geometric spreading of 1/r we have estimated Q factor for S-wave attenuation by characterizing spectral amplitude decay with distance at discrete frequencies. We propose the form of Q(f)=73f^0.72 for attenuation of S-wave in Tehran province. We show that the proposed attenuation quality factor is in the range of Q factors that have been proposed by the other studies. We have also estimated source parameters, such as seismic moment (M₀), corner frequency (f_c) and Brune stress drop (Δσ) for each earthquake. We have fitted Brune source model to the observed spectra of motion by a grid search for least squares. Stress drop for studied earthquakes ranges between 7.7 to 37.1 MPa (77 to 371 bars).

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 This study is aimed at clarifying the effect of differences in the welding depth and leg length on the initiation and growth of ductile crack in the steel beam-column connections. Cyclic loading experiments are conducted using specimens with weld defects inherent in the beam-column connection. As a result, the weld leg length has significant effect on crack growth points was revealed. Cracks tend to growth at the point where weld leg length is small. Also where the weld depth is small, crack does not growth if the weld leg length is sufficiently large.

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 Recently, a lot of earthquakes occurred in Japan. Damage has expanded because the risk acknowledgment to the earthquake was insufficient. It began to work on the individual disaster mitigation activity in a lot of regions. However, there is a big individual variation at the risk acknowledgment level in each region. This individual variation is an evil of the activity. In this study,the questionnaire was done partially of the risk management research on the regional disaster mitigation advancement to the earthquake and tsunami disaster in Wajima City harbourfront area that experienced an earthquake of recent year. A research to improve resident's disaster awareness and knowledge will be advanced in the future. The problems for that must be solved one by one.

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 The travel distances and means of transport for tsunami evacuation in urban area of Ishinomaki city were investigated. The survey data was based on responses of 797 cases for questionnaire about the evacuation from the tsunami in the great east Japan earthquake disaster. The questionnaires were collected from people living in the temporary houses in Ishinomaki city. Following findings were obtained. 1) Half of respondents evacuated by cars. 2) 90% of respondents who evacuated on foot moved to places within 1km distance. 2) 40% of respondents who evacuated by cars moved less than 1km. 3) A quarter of respondents who evacuated by cars came back to their homes once and they had only 17 minutes in average left to evacuate. 4) Two fifths of respondents who evacuated by cars were in traffic jams.

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 In the sea of Japan side, the possibility of tsunami generation by ocean trench type of earthquakes may be low, therefore investigation and study of tsunami measures against this type had been insufficient than the Pacific Ocean. In the above situation, based on what has been discussed, like the Central Disaster Management Council after the Great East Japan Earthquake and the knowledge of the past, Some tsunami sources acting on Ishikawa Prefecture as big impact were selected. And then the simulations of the tsunami intrusion on the land were performed. Tsunami source were set in consideration of the integration of active faults from marine geological survey of previous results. Tsunami analysis was performed using the latest LP terrain data. It was conformed that the assumed Tsunami source generated the tsunami bigger than historical maximum tsunami on this coastline.

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 Serious damage to levee embankments occurred in Kochi city area during the 1946 Showa-Nankai Earthquake. Relative sea level change to the land due to various factors including subsidence of land and levees, Tsunami, etc. caused massive flooding in a wide spread area of downtown Kochi. Although the occurrences of damage to levees have been fragmentarily reported through various media, no document that summarized levee damage locations on a map exists as far as authors know. This study attempts to identify locations of damage to levees in Kochi city by utilizing every available kinds of information sources including damage maps, newspapers, books, photos, and first-hand accounts. Newly found information is also utilized to identify locations of levee damage.

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 An experimental production of the three stage seismic intensity meter is demonstrated. The system consists of general JMA seismic intensity meter and EEW receiving terminal. It broadcasts three kinds of seismic intensities, 1) seismic intensity estimated from initial stage of observed P wave on site (P-wave sensor), 2) seismic intensity estimated from source information broadcasted by Earthquake Early Warning (EEW) network, 3) seismic intensity calculated from observed strong ground motion at the site. Installing the three stage seismic intensity meters, 1) post facto broadcasting area of EEW network is expected to be trimmed, 2) people around the seismic meter can be ready for strong ground shaking beforehand, 3) estimated seismic intensity is confirmed with observed intensity.

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