The evaluation of earthquake motion is basic problem in the earthquake engineering. In this study, the four-dimensional feature vector representing characteristics of duration of earthquake motion is defined based on the discretized probability mass function form of Husid plot of acceleration time histories. The feature vector is composed of average, standard deviation, skewness and kurtosis corresponding to first raw moment and second to fourth central moment of the PMF, respectively. As a case study, the proposed method was applied to the earthquake motions observed from the 2011 off the Pacific coast of Tohoku Earthquake. It was confirmed that the feature vectors well represented the duration characteristics. Next, the algorithm of SOM (Self-Organizing Maps) was applied to the set of feature vectors. The duration characteristics were visualized in a systematic way by the two-dimensional mapping using SOM.

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 In this paper, a simple methodology giving the necessary control force and allowable displacement of the friction-type damper was proposed in order to meet the demand with regard to the maximum ductility of the structure. This method took into consideration the various conditions: seismic intensity, its frequency character, natural period and yielding coefficient of the structure, and so on. The results of simulations were expressed by a simple design nomograph as functions of structural natural period and yielding ratio of induced motion to yielding seismic coefficient of the structure. Finally, effect of predetermined conditions to the required performance of the friction damper was also discussed.

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 This research is focused on the damage estimation of the underground reinforced concrete structure placed on the fault line in case of the fault rapture. Bond properties between the structure and bedrock are considered as a contribute factor which can have an effect on the damage process, fracture modes, and the limit fault dislocations.
 Three-dimensional nonlinear FE analyses were performed to investigate behavior of underground RC culvert using bond properties derived from bond strength tests. These analyses showed that the stiffness of bedrock and the friction force had an effect on them, on the other hand, bond strength had a small effect.

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 The 3-D model of surface deformation was made by aerial photogrammetry and the GNSS surveying was also done in the actual ground, in order to clarify the surface deformation by the 2016 Kumamoto Earthquake. At the verification points, the accuracy of the constructed model was verified. The surface deformation was analyzed by overlaying the 3-D model after the earthquakes on the 3-D model before the earthquakes using GIS. The difference between the DEM before the earthquakes and the DEM after the earthquakes was analyzed in Matoishi and Nagakusa area, Aso-shi. As the result, the vertical surface deformation could be found two-dimensionally and quantitatively. The coordinate values at the center of gully holes and manholes before and after the earthquakes were also measured in Yasunaga area, Mashiki-machi. As the result, the horizontal surface deformation could be found two-dimensionally and quantitatively.

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 At 21:26 JST on April 14, 2016, an M_w 6.2 earthquake struck Kumamoto city in Kyushu, Japan. Around twenty eight hours later, at 01:25 JST, an M_w 7.0 stronger earthquake occurred, in the same area. Field investigation and inspection were conducted to study an effect of inclination of the house due to liquefaction to health problems of residents. An overview of liquefaction triggered by the 2016 Kumamoto earthquakes is presented, based on our reconnaissance investigations that conducted on May 27 - 30, 2016 in Kumamoto City and vicinity area. The tilt angle of 68 houses and buildings in liquefied sites of Kumamoto city was measured. Based on the measurements, the degree of inclination is seem to be related to the type of the houses and buildings. Furthermore, the tilt direction of the houses and buildings has a tendency associated with direction of old river slope. In addition, it is also found that the tilt direction of the houses and buildings is related to the terrain as well.

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 Since we have concerned about the occurrence of large earthquakes in Tokyo area and Nankai trough, we are examining seismic measures for special levees in the city center. However, the detailed research of the special levees behavior induced by earthquake has not been promoted enough until now. The seismic countermeasure of special levee is designed by level 1 ground motion now. In this study, damage to special levees in the 2016 Kumamoto earthquake was compared to past earthquakes. We analyzed effects of earthquake motion on damage to special levees were investigated using observed motion recorded near the damaged special levees. Based on these results, problems of seismic design for special levee were pointed out.

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 In the 2011 off the Pacific coast of Tohoku earthquake, strong ground motions and tsunami caused damage to a large number of highway bridges in broad area. The existing study showed that the longer bridges or continuous girder type of bridges tend to have larger damage ratio. In this study, damage to highway bridges is statistically studied focusing on difference in damage-ratio and degree due to design codes, plane shapes, etc. The result statistically showed that the bridges designed in accordance with the post-1990 design codes tend to have less damage and that damage to the bridges designed in accordance with pre-1980 design codes has been reduced by seismic retrofit.

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 In the present study, a hydraulic experiment with moving bed was carried out in order to investigate the influence of particle size of sand, slope of run-up areas, and tsunami conditions, to distributions of sand deposited on land slopes by tsunamis. Then, the following matters were examined by using experimental data; the relationship between the run-up distance and deposit formation distance, the relationship of the distribution of the sediment and the incident wave, the difference in the distribution of the deposit due to the difference in particle size of the source sand, the distribution of the deposit by uniform sand and mixed sand. From experiment results, it is shown that the ratio of deposit formation distance and tsunami run-up distance is influenced 0.67 to 1.0 by particle size of sand. This ratio is also changed by slope condition and tsunami wave settings. And the mass distribution of deposit is changed by the particle size of source sand. When utilizing tsunami deposits, it is necessary to consider not only layer thickness but also particle size.

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 In order to make clear the seismic behavior of embankments under cold snowy condition, the field measurement of an embankment and the evaluation of seismic resistance of embankments by numerical simulations were conducted. Firstly, the freeze and thaw behavior of moisture and mechanical properties were evaluated by ground temperature and volume water content observation, cone penetration test. Then, a series of the numerical simulations were conducted by use of soil-water-air coupled analysis. It was revealed that the seismic resistance of embankments decreased, especially in the case of low embankments. The reason of the decrease of the seismic resistance was estimated to be the change of the boundary of pore water and pore air at the surface of the embankment.

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 It is necessary to evaluate seismic coefficients for open-type wharves against Level-one earthquake ground motions in the practical design, however, the evaluation method of those for open-type wharves with pneumatic caissons has not been established yet. In this study, two-dimensional earthquake response analyses on open-type wharves with pneumatic caissons were conducted for earthquake ground motions with different predominant frequencies. It was made clear that the evaluation method of seismic coefficients for open-type wharves with pneumatic caissons is different from that for open-type wharves with steel pile foundations. The optimum calculation positions of acceleration response spectra were found to be foundation bottom levels. The optimum damping constants for the calculation of maximum response acceleration were found to be in the range of 5% to 20%.

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 In order to assess earthquake resistance of new or existing structures and predict earthquake damage of structures, it is important to properly evaluate the response of the structure at the time of the earthquake. In cold regions where the ground may freeze in winter, the possibility of a change in the dynamic interaction phenomenon can not be denied because it is affected by the density of the ground and the shear wave velocity. Therefore, we examined the influence of freezing of ground on the behavior of the structure by examining the interaction between the frozen ground and the pile.
 As a result, it was shown that group piles in the frozen ground tend to follow the behavior of the ground in a wide band. Furthermore, it was shown that even when the ratio of the freezing depth to the characteristic length indicated by the rigidity ratio of the ground and the group pile is small, the rigidity at the time of freezing becomes very large. It was confirmed that the freezing of the ground greatly affected the interaction between the ground and the pile.

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 In this study, methods of aseismic retrofitting were developed for abutments in which soil-mixed column walls are linked to abutments along the sides of tracks, utilizing ground improvement techniques. A shacking table test in gravity field was conducted on a model scale of 1/15 to verify the effect of the proposed method. As a result of the shaking table test, the backfill, which was located between the abutment and the soil-mixed column walls, behaved together with the abutment and the soil-mixed column walls. The abutment collapsed in sliding mode and a failure plane was formation that on the backside of the soilmixed column walls. Thus, it was confirmed by experiment the proposed method improves earthquake resistance since the soil-mixed column walls resisted external force by the subgrade reaction and shear resistance at the bottom and the sides of the soil-mixed column walls during shaking.

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 In safety estimation of nuclear facilities, it is required to estimate the risk of earthquakes even stronger than assumed in design. The authors have proposed a simple model by the distinct element method to evaluate the traveling distances of the collapsed rock mass when slope collapse happened. There, reproduction simulation was carried out for a 0.8m height collapsed slope and results of the accumulation distribution of the traveling distances of rock mass were comparable or conservative.
 However, for the restoration plan of access routes assumed to be occluded by the collapsed sediment the estimation of collapsed sediment volume is necessary, since only the conservative estimation for the collapsed distances of sediment is not enough. In this study, reproduction simulation is carried out for the ground of Nakadori area of Fukushima Prefecture, damaged by the 2011 Tohoku-Pacific Ocean Earthquake. Based on the proposed simple model its reproducibility is shown and friction effect to both collapsed distance of sediment and volume of deposit is discussed.

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 Liquefaction-induced lateral spreading has imposed damages to structures during past earthquakes. This paper presents experimental results of a series of 1-g shaking table tests on models reinforced with gravel and geosynthetics subjected to liquefaction-induced lateral spreading. Firstly, observations linked with the mechanism of lateral spreading based on the test without remedial measures are presented, followed by the results based on the test with remedial techniques by using gravel only and then gravel combined with geosynthetics as well. Furthermore, in order to obtain the additional results from the use of gravel and geosynthetics, further tests were done by varying the position of the geosynthetics in the gravel, which were at the bottom, in the middle, and at the top of the gravel layer. General test results including time-histories of accelerations, pore water pressures and displacements are presented and discussed in this paper. The results indicated that by applying the proposed mitigation measures, the seismic performance of the soil models can be improved by reducing lateral ground displacement, which best results obtained from soils reinforced with geosynthetics at the bottom and in the middle of the gravel layer.

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 The authors investigated the damage of water tanks, elevated tanks and distributing reservoirs in Kumamoto Prefecture during the 2016 Kumamoto Earthquake and clarified the characteristics of the damage from the viewpoint of sloshing and bulging. Through the comparison between the locations of the damaged tanks and the contour maps of the response spectra, obtained from a lot of strong ground motion records, we found that there is a good correspondence between them and that the damage of sloshing and bulging can be verified due to the appearance of short- and long-period earthquake response which exceeds the maximum design values in the present seismic design regulations.

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 Water cycle facilities are usually constructed at coastal area because of sewage collecting system by gravity flow. So, seismic performance against not only earthquake motion but also tunami should be secured. In this study, we have proposed isolation structural method against strong earthquake motion and wave force of tsunami by utilizing asphaltic viscous fluid isolator. Effectiveness of the proposed method was examined by three-dimentional FEM analyses. As a result, it is considered that stress within the structure induced by earthqauke motion and tsunami can be largely reduced by buffer effect of isolator.

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 For the Tsurumi Tsubasa cable stayed bridge, this study revealed the dynamic characteristics based on analyses of the seismic records by the aftershocks of the 2011 off the Pacific coast of Tohoku earthquake. We estimated the dynamic characteristics of natural frequencies and vibration modes by spectral analyses of the recorded accelerations. We identified modal parameters of the bridge by using multi-degree-of-freedom- system model consisting of super-structures, piers, and foundations. The natural frequencies and damping coefficients of the bridge were identified by analyzing the transfer functions of girder and tower records with respect to the foundation record, compared with the theoretical transfer functions.

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 Many people could/did not evacuate from the 2011 Tohoku Tsunami. Solving problems of the evacuation start is very important to mitigate human losses due to tsunami disasters. In the present paper, we have been developing the evacuee generation simulation based on the viewpoint in which various agents in our society play an important role in the start of tsunami evacuation. In this research, using “Digital Archiving of the Great East Japan Earthquake Survey” and “Evacuee Generation Model”, we analyzed the start of tsunami evacuation in the 2011 Tohoku tsunami in Shidugawa, Minamisanriku. The results revealed that (1) many residents in their offices or stores headed evacuation sites after they went back home, (2) most residents move outwardly from the center of the town, and (3) residents in the suburbs of the town could start evacuation easily because of the reality of imminent emergency which prompts the need for evacuation constructed by many residents.

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 At the time of an earthquake disaster, medical institutions become an important base. However, since medical institutions are also damaged, it is necessary to understand the state of the medical institution at the time. Therefore, in this research, a questionnaire survey was conducted for areas considered to have been affected by both building damage and lifeline damage due to the Kumamoto earthquakes. The survey results revealed that it was the water outage that had the greatest influence on the medical function due to lifeline damage. In addition, it was found that in the institution where damage caused by facility damage is large and the damage of the elevator is caused, it is easy for a leave of absence or transfer to occur. Furthermore, it was found that the influence of the toilet unavailability is the largest in the plumbing/drainage facility. It is thought that there is a possibility to reduce the damage by performing disaster prevention measures based on these and to grasp the situation quickly.

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 This study investigates the effects of initial cyclic loading history on anisotropy of small strain shear moduli and liquefaction properties of Toyoura sand (D_r=50%, 65%, 75%). In order to investigate variation of the liquefaction resistance and small strain shear moduli of the specimens caused by initial cyclic loading, a series of static and dynamic measurement methods were conducted. It was found that the small strain shear moduli of the specimen changed by the drained or undrained cyclic loading history, and there is a good correlation between the small strain shear moduli and liquefaction resistance at each relative density series. On the other hand, we discussed the development of strain and excess pore pressure of specimens with different relative density.

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 Serious damage of wooden houses was occurred in Oyatsu cluster, Mashiki Town, Japan, during main shock of the 2016 Kumamoto Earthquake. In this study, first, microtremor measurement with high dense spatial location was carried out in the cluster. Next, temporary aftershock observation was conducted in the cluster site in order to evaluate the site amplification and phase effects. Finally, based on the local site effects and the characterized source model, ground motions during the 2016 main shock were estimated. The estimated ground motions are will be useful in the detailed study of the failure mechanism.

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 Slope failure of expressway embankment was occurred in the abutment site for Akitsu River Bridge during the foreshock of the 2016 Kumamoto Earthquake. Therefore, to clarify the failure mechanism, it is necessary to estimate ground motions in the damage site with sufficient accuracy, taking into account local site effects. In this study, seismic waveforms in the damage site were estimated based on the extended site-effect substitution method considering location of the strong motion generation areas. The site effects in the damage site were also evaluated based on the temporary aftershock observation.

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 Serious failure of masonry retaining wall was occurred in Kumamoto Castle due to the 2016 Kumamoto earthquake sequence. Therefore, to clarify the failure mechanism, it is necessary to estimate strong motions in the castle with sufficient accuracy, taking into account local site effects. In this study, seismic waveform in the castle was estimated based on the site-effect substitution method. The site effects in the castle were evaluated based on microtremor measurement with high dense spatial location. Difference of the site effects between the castle area and the present observation stations was also indicated.

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 During a northern Noto peninsula scenario earthquake, not only strong motion but also huge tsunami is attacked in Hegura Island, Wajima City, Japan. In this study, first, seismic waveforms in Hegura Island were estimated based on the asperity models with consideration of ground shaking characteristics by microtremor measurements. Next, walking times from the sites of interest to designated refuge place were measured based on in-situ investigation. Finally, using the non-evacuation time during the earthquake and the required evacuation time after the earthquake, we evaluated the difficult area for tsunami evacuation in Hegura Island taking into account the tsunami travel time.

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 Generally, prediction of ground motions have been carried out for every grid square by NIED, Japanese Cabinet Office, Local Government Office and so on. In other words, it is assumed that the ground shaking characteristics in the grid square of interest is almost uniform in the ground motion prediction. In this study, ground motion estimation with high dense spatial location for a 3rd grid square with almost 1 km², in central Miyoshi City, Tokushima Prefecture, Japan, during the Nankai Trough scenario earthquake are carried out based on the SMGA models considering the empirical site amplification and phase effects.

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 In this study, full-scale shaking table tests for embankments were carried out in order to estimate the earthquake resistance of small earth dams with geosynthetics clay liner for a short supply of clay material which requires sloping core zones at many sites. In the experiment, two types of embankments of 3 m of height were constructed in large soil containers respectively. The dynamic behaviors of embankments were observed by sinusoidal wave of maximum acceleration of 471 Gal. After shaking, several longitudinal cracks without water leakage were occurred at the crest of the embankment with geosynthetics clay liner. Finally, a series of the three-dimensional terrestrial laser measurements was tried to grasp the characteristics on the residual deformations of the embankments. As a result, it was found out that some locations and forms of the cracks can be confirmed relatively. Therefore, it was indicated that three-dimensional terrestrial laser scanner is effective as a utility of the measurement method.

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 In order to install the facility close to the slope that could collapse during an earthquake, it is necessary to predict the slope failure shape and ensure a proper separation distance. There is a difference in the methods of guidelines applied to the estimation of the reach of sediment flowing out by the slope failure. The issue is how to set the appropriate separation distance.
 In 2016 Kumamoto earthquake, a lot of slopes collapsed. Therefore, a survey was conducted into selected typical slope failure. The outflow reaching distance of collapse sediment was analyzed, and the evaluation methods based on slope height of guidelines were compared. Also we investigated the influence factors on the outflow reaching distance other than the slope height.

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 Although the performance-based design framework has been introduced to almost all the technical standards, the practical design follows all the specifications stated in the technical standards. Authors discussed the evaluation method of the design input earthquake ground motion considering source, path and site amplification characteristic of the site of interest in the performance-based design framework. The evaluated source and site specific earthquake ground motion, in this sample case where large earthquake is not expected and local site condition is very stiff, is shown to be smaller than those specified in the technical standards.

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 Aftershock and microtremor observations were conducted in the vicinity of surface fault ruptures at suburbs of Mashiki town due to the 2016 Kumamoto earthquake. Our target of the observations is searching out the difference of ground motions between surface faulting areas without severe damages and severely damaged areas without surface faulting. From aftershock observation, ground motion at damaged site is larger than that at surface faulting site without damage, however, average difference of JMA seismic intensity between the two sites are less than 0.5 while estimated difference from witness and real damage is more than 1.0. From microtremor observations, H/V spectra at surface faulting regions are rather flat and do not to have steep peak while clear peaks are observed around the faulting areas.

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 The purpose of this paper is to develop a new earthquake-resistant design and a new countermeasure for telecommunication conduits against large earthquakes. The paper discusses the countermeasure, which doubles pipes by lining, through both experimental and analytical methods, considering failure mechanism of optical cables. Specifically, three next actions were assumed: when the joints of pipes collide during compression-tension cyclic loadings; when permanent ground displacement due to liquefaction, subsidence or collapse of ground occur; when the protection concrete fractures and the shearing stress act on the cables. It was found that even though the failures at the joints of pipes occur, the cable-laying conduit lining can still contain the essential function to keep space for cables and to prevent the disruption of cables.

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 Although the performance-based design framework has been introduced to almost all the technical standards, the practical design follows all the specifications stated in the technical standards. This paper aims at showing new earthquake resistant design examples in the performance-based design framework that designers apply the appropriate method according to the design conditions regardless of the specifications in the technical standards. Authors discussed the design results of railway bridge, highway bridge and quay wall considering both source and site specific earthquake ground motion and those specified in the technical standards.

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 In this paper, the experiments are shown for analyzing the intensity characteristics of screw joint for steel pipes which is the majority telecommunication pipeline system. The screw joint of steel pipes accounts for a large number in telecommunication pipelines. In addition, it is also known that the steel screw joint is tend to be damaged compared to other types of steel joints from the experience of past earthquake studies. Therefore proper seismic countermeasures are required. In order to apply the seismic countermeasures efficiently, it is necessary to make a priority order according to the intensity of screw joints. To achieve this, experiments have been done to analyze the intensity characteristics of steel screw joint. From the comparison of experiment results and structural analysis, the destruction conditions of steel screw joint are clarified.

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 Approximately 4,600 residential lands were determined as "danger" or "caution" by the 2016 Kumamoto earthquake. It caused extensive damage to the embankment of residential lands, such as slope failure and collapsed retaining walls. Therefore, the authors have provided information for the survey results of large-scale embankment-developed lands in Mifune-cho, Uto city and Minami Aso Village, after the earthquake. From the results, countermeasures for the earthquake resistant project; launched by the Land, Infrastructure and Transportation Ministry, were carried out in Mifune-cho and Uto city. In this paper, the authors discussed the damage survey results of the large-scale embankment-developed lands in Mifune-cho and Uto city.

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 Shikano and Yoshioka earthquake fault occurred on the surface by the 1943 Tottori earthquake. In this study, subsurface structures were determined and we grasped characteristics of ground motion by microtremor and gravity survey in the Shikano area, Tottori Prefecture. Microtremor single-point 3-components observations and array observations were carried out at 304 and 34 sites respectively. As analysis of microtremor surveys data, we estimated S-wave velocity structures by using phase velocities obtained from array observations and predominant periods of H/V spectrum obtained from single-point 3-components observation records. Gravity observations were carried out at 38 sites. As analysis of gravity surveys data, gravity anomalies with assumed density in 2.43t/m³ were obtained by using gravity databases, existing data in the east-part of Tottori Prefecture and this study data. 3D density structures from the distribution of gravity anomalies were estimated.

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 Each municipality has been conducting the seismic assessment based on empirical methods with simple seismic strengths such as PGV (Peak Ground Velocity), PGA (Peak Ground Acceleration) and SI (Seismic Intensity) by considering geomorphology effects. Improvement of the strong motion evaluation has been mainly performed for urban region where social capital and population were concentrated. However improvement of the strong motion estimation in mountain regions is crucial for mitigating secondary damages induced by collapse of natural slopes and road embankments on mountain side. In this study, we conducted the seismic observations at the small mountain in Yokosuka city, including an underground site, and we investigated the frequency characteristic of the amplification factor of mountain topography.
 The main result are summarized as follows; the frequency characteristic of the amplification factor is close to 1 at the range of larger than period of 1.0 second; The amplification factor increases as the altitude becomes high.

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 Railway structures continuously exists in a long section of the railway line, so there is a possibility that the performance of the entire railway may be impaired by an earthquake even if the seismic damages are local. Therefore, it is important to extract the weak points by evaluating seismic capacity of the entire railway structures. Authors have developed the earthquake disaster simulator which can simulate seismic response analyses of the entire railway structures. However, it takes a lot of time and cost in order to model large number of structures in accordance with the seismic design. In this paper, we have established several analytical models of reinforced concrete viaducts which have been different from the models in accordance with the seismic design, and conducted sensibility analyses regarding nonlinear responses obtained by push over analyses. As a result, we have clarified the efficient modeling method for large number of reinforced concrete viaducts.

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 This report presents method for detecting damage of bridge column using vibration data. In condition of knowing both input and output of the structure's motion, change of characteristics of vibration can be analyzed. First it is reported that hysteresis of vibration data by experiment can give simple result for damage detection. Next it is shown that plastic ratio of response is better index of damage by using non-linear dynamic analysis results. Furthermore it is explained that dynamic inclinometer is effective in order to estimate relative displacement. Using this, damage of bridge column can be estimated by single observation point on column top.

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 In the guideline for seismic design of river structures, static analysis is usually applied to calculate the deformation of a river embankment. Dynamic effective stress analysis is advisable in the cases that large measures are conducted or detailed examination is required due to land use status. However, dynamic effective stress analysis has not yet established as a stably applicable method because it needs special knowledge and has technical difficulty in setting parameters. In this paper, we studied points improve accuracy of dynamic effective stress analysis based on the detailed investigation of the ground at Naruse River R0.8km and Yoshida River R16km and the simulated behavior of the embankments during the 2011 off the Pacific coast of Tohoku Earthquake.

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 On April 14th, 2016, an inland crustal earthquake of Mw 6.2 struck Kumamoto region of Kyushu Island, Japan. The earthquake generated strong ground motions near the source area. Seismic intensity 7 of the JMA was recorded in Mashiki town. Approximately 1 day later of this Mw 6.2 earthquake, an intensive earthquake with Mw 7.0 hit the affected areas again. Many houses were damaged at Mashiki town by a series of the earthquakes. We attempt damage assessment of the houses by using the aerial photographs before and after the earthquake of mainshock.

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 The following article has been retracted at the authors' request, because of potential problems with the data at temporary observation stations used in the manuscript.
 Atsushi NOZU, Yosuke NAGASAKA: PRELIMINARY ANALYSIS OF NEAR-SOURCE STRONG MOTION RECORDS DURING THE MAIN SHOCK OF THE 2016 KUMAMOTO EARTHQUAKE —CAUSE OF DAMAGING GROUND MOTIONS IN MASHIKI—, Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)), Vol. 73, No. 4 (JSCE Journal of Earthquake Engineering, Vol. 36), pp. I_959-I_969, 2017.

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 Approximately 28 hours later of the Mw6.2 earthquake which occurred at Kumamoto region on 14th April 2016, an intense earthquake with Mw7.0 hit the affected areas again, and JMA seismic intensity of 7 was observed. It is considered from a CMT solution and after-shock distribution that the mainshock of Mw7.0 was caused by ruptures of Futagawa fault. Strong ground motions were generated near source area and caused severe damage to many structures. The authors conducted a damage investigation along the Futagawa fault. Furthermore, we make a preliminary source model by the empirical Green's function method using forward modeling procedure. This paper reports structural aspects of the damage observed along the surface rupture of Futagawa fault in Nishihara village and characterized source model of the Kumamoto earthquake.

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 In Nakahara, a residential area in Mifune Town, serious damage was caused by the 2016 Kumamoto earthquake sequence. 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 foreshock and the main shock with high accuracy by taking into account site effects. In this study, we evaluated the similarity of the empirical site amplification and phase effects between Mifune Town Office and the residential area based on results of microtremor measurements and temporary earthquake observation.

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 Serious failure of Kinoura Tunnel and collapse of Suzu-Hachiman Shrine was occurred in Suzu City, Japan, during the 1993 Off Noto Peninsula Earthquake. In this study, first, microtremor measurements were carried out in the damage sites of interest and the surrounding station sites. The pseudo point-source model for the 1993 main shock was then constructed based on the similarity between the observed and the synthetic ground motions at JMA Wajima. Finally, based on the results of the measurement and construction, ground motions at damage sites of interest during the 1993 main shock were estimated.

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 A standard test method is proposed for the cyclic shear test considering the recent trend that design earthquake motions become large. At first, various test conditions that can be used in the current test specification are examined, which are drained and undrained, stress control and strain control, and number of loading cycles, etc. It is found that these conditions hardly affect the cyclic shear deformation characteristics up to strain of 0.06%, but results by different test conditions are different to each other at strains larger than 0.06%. Cyclic shear deformation characteristics are also depends on operator's decision at large strains. A test method under the undrained condition, strain controlled amplitude, and three effective loading cycles is proposed as cyclic shear test considering previously discussed effects and matching with constitutive models. Finally, preferable data output is suggested when other test conditions are used.

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 In this paper, series of shaking table tests of embankments in different water content were conducted in order to clear the seismic behavior of unsaturated embankment and the effect of the slope protection works. Thought the rainfall was applied before the shaking, the water contents of the embankment were in unsaturated conditions with or without slope protection works. Due to the maintenance of the unsaturated conditions, two embankments in different water content showed similar behavior. Furthermore, the stability analyses of the shaking table tests of the embankment were carried out. The calculated results showed that the appropriate evaluation of embankment material considering unsaturated soils is important.

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 In this study, the surrounding of the Wajima City harbor area where the Noto Hanto Earthquake was experienced in 2007 is targeted. The evacuation route in the region is discussed by simulating the cases that a refuge instruction are parameters, Earthquake tsunami evacuation simulation using the GIS data which Wajima City held and multi agent system is conducted.

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 Deformation analysis and trial study for structural monitoring using C-band synthetic aperture radar (SAR) on Sentinel-1 satellite for Kumamoto Earthquake is described. C-band SAR data is expected to excel at distance (phase) resolution to conventional L-band SAR data. Major ground surface displacement before/after Kumamoto Earthquake is confirmed by interferometric SAR (In-SAR) analysis. Also, sever structural deformation is detected from reflected intensity image. However, small structural movement is not able to evaluated due to the limitation of ground resolution.

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