The framework of screening techniques for clarifying seismic vulnerability of buried telecommunication pipes was proposed. In the 1st screening, seismic vulnerability of targeted pipes is ranked by four classes for seismic retrofit by using the modification factors showing the relations among damage ratios from the type of pipes, the span length and the microtopography: the highest, higher, moderate, and less priority classes. In the 2nd screening, seismic damage functions are applied to rank up the priority classes for checking the risks of failures of pipes exposed by higher seismic intensity levels. Case studies for the check of the validity of proposed screening techniques by applying observed damage data were shown.

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 It is important to evaluate the residual performance of bridge structures with aging deteriorated rubber bearings by carefully considering their uncertainty in deformation capacity. However, it is difficult to estimate the probability distribution of the ultimate strain of the bearings as there are only very limited number of test data. In this study, Bayesian estimation is performed to investigate the probability distribution and variation in the deformation capacity of aging deteriorated rubber bearings. Besides the tested ultimate strain of 4 aging deteriorated bearing samples, probability distributon from 112 new bearings' test resuts are used as pior-distribution. Increamental Dynamic Analysis (IDA) were conducted to evaluate the seismic performance of deteriorated structure with radom ultimate strain of bearings due to the estimation. The few numerical models' IDA were conducted and their their fragility and probobal damage mode under large earthquake were calculated for decision making issues such as the nessessary of changing the bearing to new ones or reinforcement of the sub-structure.

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 Generally, the seismic performance verification of the civil structure in the process of seismic design is evaluated by spectrum-compatible time histories combination of both a horizontal and vertical directions. With the advanced seismic design method and analysis method, it is necessary to generate two orthogonal horizontal directions for seismic design considering three dimensional behaviors.
 This paper presents a synthetic method for both uniaxial response spectrum and bi-axial response spectrum compatible accelerograms by the concept of Lissajous curve. In addition, an example of bidirectional accelerograms by proposed method is indicated using the response spectra ratio of the characteristics of observed strong motions.

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 This study discusses evacuation planning from tsunami disasters due to the difference in evacuation conditions at the low-lying area in Kushiro City. A series of surveys and GIS analyses were carried out in previous studies. In snowy and cold district in winter, a range of refuge for tsunami evacuation decreases because of the decrease of walking speed and impossible to stay outdoors. If it is possible that the early evacuation and more people take in temporary refuges, this range of refuge increases significantly. Therefore, we estimate the effects of travel time to refuge buildings. The result shows that it is difficult to evacuate by the early evacuation only in some areas. Therefore, temporary refuges need to be constructed in such area.

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 Many of the residential land were damaged by the 2014 Nagano Prefecture in northern earthquake. So, Nagano Prefecture was sighting survey of residential land damage to 23 from 25 November. The risk assessment of residential land was conducted Hakuba, Otari-mura, Omachi and the Ogawa village, in early December.
 This paper was analyzed for each district and damage item for damage situation from the survey results. Great damage is concentrated in places where fault is exposed on the ground surface in Hakuba village of Horinouchi district. In other districts, it was revealed that ground damage of landslides due ground motion is remarkable.

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 Past experience has shown that port structures are often susceptible to severe damage during major earthquakes. From field observation of 1995 Hyogo-ken Nambu earthquake, it is observed that the seismic behavior of port structures such as caisson-type quay walls shows significant variability due to the variation in soil properties. In this study, seismic response analyses using a two-dimensional FE mesh, representing a caisson-type quay wall located in Rokko Island, are performed to carry out the sensitivity analysis the seismic performance of the caisson-type quay wall. To investigate the effect of uncertainties of soil properties on the dynamic behavior of the quay wall, a tornado diagram is used. It has been found that the uncertainties in the friction angle of reclaimed soil contribute most to the variability of the residual displacement and inclined angle of the quay wall. In addition, a Monte Carlo simulation considering the variation in soil properties has revealed that taking into account the effect of geometrical nonlinearity by using a large deformation analysis makes it possible to rationally assess the seismic performance of port structures while infinitesimal deformation analyses can overestimate the effect of the variation in soil properties on the deformation of port structures during earthquakes.

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 In the Great East Japan Earthquake, the high speed train (Shinkansen) operation system had stopped for long time, because a large number of overhead catenary system poles (OCS-poles) of pre-stressed concrete on Shinkansen viaducts had fell down even though the viaducts were not severely damaged. Thus, the seismic performance of the OCS-poles should be clarified and improved shortly by realistic techniques. In this study, firstly building a three-dimensional coupled frame model of four-block Shinkansen viaducts including OCS-poles and catenary cables, seismic response analysis was conducted and the dynamic response properties of the viaducuts and OCS-poles have clarified. Secondly, based on those results, a vibration control technique using TMD to ease damage of OCS-poles was proposed. Finally, conducting some simulations and referring to various material on TMD, the advantage of the proposed technique to the conventional ones improving seismic performance of OCS-poles in terms of function, cost, workability and maintenance was shown.

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 It is often at issue that due to hard site conditions including required temporary works, dredging in the river and headroom constraints, earthquake-resistance retrofitting works are difficult and cost-consuming for existing bridge piers. For solution, we have developed a new method. In addition to pressing into the riverbed and installing steel plates around piers, this method ensures strength of pier ends against bending moment force by extending rebars into the existing footings. This paper reports the experimental results of the new retrofit method on its construction practicability and quality, hysteretic characteristics, cyclic loading tests, reinforcement effectiveness, etc.

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 This study is aimed to investigate cracking mechanism of welded steel T-type joints. Crack initiation, propagation and rupture of the joints were studied using cyclic bending loading. Effect of post-weld treatment, notch and notch position on cyclic performance of the joints was studied. As a result, post-weld treatment can delay crack initiation and notched joints are apt to crack earlier than those notchless ones. Notch close to the boundary between the fusion zone and heat affected zone can accelerate the crack propagatipon.

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 In this study, subsurface structures of strong ground motion observation sites in Tottori Prefecture were determined to obtain information for prediction of earthquake strong ground motion at each sites. S-wave velocity models and predominant period of H/V were obtained using array microtremor and observation 3-components single-site microtremor observations data at 43 sites. PS-P times with receiver functions were calculated using acceleration data at observation sites. Subsurface structure models were reconstructed based on the results of receiver functions and geophysical exploration. Estimation of site amplification effects by spectral inversion technique and evaluation of amplification factors of earthquake indices were carried out. We found that characteristics of amplification factors of site amplification effects and tendency of amplification factor at observation site in Tottori prefecture. In addition, we checked the relationship between site effects and transfer functions of SH-wave, average of S-wave velocities, H/V of microtremor.

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 Case study was performed into mitigation of seashore protection facilities in Kobe city against a huge earthquake such as Naikai-Trough earhquake. First, the deformation of the facilities when subjected to strong motion was estimated by means of dynamic effective stress analysis as well as an equivalent simplified method. In so doing, the liquefaction strength of foundation, i.e., reclaimed soil and Holocene sand deposit was estimated over the whole cited area by using the relationship between the liquefaction strength from undrained cyclic triaxial test and the corrected SPT N-value. Second, the area, together with the depth, of submergence inside the protected region in the event of Tsunami attack was estimated by means of numerical simulation, for which the deformation of seashore facilities prior to Tsunami was properly considered. Finally, remedial scheme of seashore protective facilities against Nankai-Trough earthquake is proposed.

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 The 2011 off the Pacific coast of Tohoku Earthquake caused diversed damage to many bridges in broad area, from Tohoku region to Kanto region of Japan. It is reported by many experts or authorities that damages were caused by not only tsunami but also earthquake ground motion. This paper reports statistical analysis results of damage to highway bridges caused by the earthquake ground motion, with linking damage investigation results of bridges and estimated seismic intensity measures at their locations, such as PGA, PGV, SI or seismic intensity. The statistical analysis results showed that the longer bridges or continuous girder type of bridges tend to have larger damage ratio, and that year of completion of bridges does not have strong correlation with their damage ratio.

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 In order to investigate the characteristics of site amplification factor around caldera, we evaluated site amplification factors based on earthquake recordings at two sites inside (the port in Satsuma-Iwojima Island) and outside (the airport) the Kikai Caldera. The result showed that there were the common peak frequency of 0.2-0.3Hz and this result suggests that there are the same deep structure inside and outside the caldera. In addition, one-dimensional transfer functions are evaluated based on microtremor measurements. It is found that the peak amplification around 0.2 Hz was not clear in the tarnsfer function at the airport. This is considered due to the effect of the three-dimensional effect of the caldera and the in-cident angle of seismic waves.

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 Recently, some studies have been conducted concerning the extending the service life of the bridges. Many bridges were built in the period of high economic growth, and they reached their service life. Consideration of rebuilding and extending the service life must be carried out. Ishikawa Prefecture conduct regular inspection of the bridges every 5 years. Damage of the bridge can be assessed by regular inspection. Soundness of bridge is determined by damage degree of the bridge, and is recorded as inspection results. The repair priority is decided based on soundness of bridge, but repair priority decision is not considered the seismic risk. In Ishikawa Prefecture, the Morimoto Togashi fault in the southeast edge of the Kanazawa plains is active faults. The earthquake such as magnitude 7.2 in 2-8% is expected to occur in near future. As a result of this risk evaluation, a lot of bridges will be affected by earthquake. The purpose of this study is to make the decision of repair priority including the seismic risk by using the regular inspecton data. It became clear that the repair priority of the bridge can be considered the seismic risk using principal component analysis.

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 It is necessary to consider the seismic safety of bridge columns with isolators subjected to extreme ground motions. The capacity hierarchy of bridge columns with isorators and ductility of reinforced concrete columns were investigated to improve repairability and safety subjected to extreme ground motions by nonlinear static analysis and fragility assessment based on dynamic response analysis in this study. It was shown that the damage is induced at reinforced concrete columns by setting hardening-initiated strength of isolator to be larger than yield strength of reinforced concrete column. Furthermore, in that case, it was shown that the seismic safety of bridge columns with isolators is improved as the ductility of reinforced concrete columns increases.

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 To develop a new generation of performance based seismic design methods for isolated bridges, it is necessary to consider the bidirectional earthquake effect. The first step is to understand the difference between seismic response of isolated bridges under bidirectional earthquakes and that under unidirectional input as assumed in the current design method. Though bidirectional loading tests and hybrid simulations have been conducted for this issue, the number of input earthquake waves are too few to disscuss the effect of randomness of the phase character of the input earthquake ground motions. In this study, the Incremental Dynamic Analysis (IDA) is conducted for isolated bridges to understand their response difference between conventional uni-directional ground motion input and real bi-directional input. A large number of earthquake waves were used to take the uncertainty of earthquake phase difference character into account. A benchmark bridge structure was simplified as a two-mass system simulation model, and the Modified Park-Wen model is used to simulate the hysteresis character of HDR bearings under bidirectional loading. The IDA curves and fragility curves were obtained from these analyses and the difference in the responses of isolated bridges under uni-directional and bi-directional seismic excitation is statistically estimated. Three methods to check the seismic performance of aisolated bridge to satisfy the design criteria are proposed.

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 Based on the investigation results on the reasons relating to the 2009 Suruga Bay Earthquake, the urgent inspections and seismic assessments on the highway embankments have been conducted. Because the seismic design ground motions were revised newly in the 2011 Off the Pacific coast of Tohoku Earthquake, the above seismic assessments were necessary in detail to investigate the effects of the former and newly revised seismic ground motions. Then the seismic assessments at 3 different road embankments from the view of the performance-based design were conducted to estimate the sliding residual displacements induced by the 6 different seismic ground motions with use of Newmark Sliding Block Method. As the results, the effects on the sliding residual displacements induced by the different type of seismic ground motions are discussed.
 In this paper, the effects of seismic response of embankments during the earthquake are investigated, and the sliding residual displacement due to the difference in the type of seismic ground motion are discussed. In addition, from the correlation of the yield seismic intensity and the sliding residual displacement, the simple estimation method of the sliding residual displacement in level 2 ground motion was proposed.

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 A tsunami damage analysis was conducted in order to simulate process of damage to a highway bridge of which superstructures were washed out in part by the tsunami of the 2011 off the Pacific coast of Tohoku earthquake. A precise model of the bridge and surrounding terrain and a sluice was constructed and a 3-D multi-phase flow analysis was carried out. The analysis shows that uplift force acting on the superstructures washed out was larger than the strength of bearings. Air trapped between girders was found to play an impotant role on the large uplift force.

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 It is designated as Emergency Transportation Road linking between disaster prevention bases in which to smooth Emergency Transportation. It is assumed that Emergency Transportation Road is damaged by disaster. However, little study has been done to research in such the consideration. In this study, it is analyzed the accessibility using Emergency Transportation Road between prefectural office and municipal office in consideration of flooding of roads by the river disaster, road blockage due to collapse of the roadside building by an earthquake and these complex cases. With the result that there are many flood risks that becomes unreachable until the municipal offices on Emergency Transportation Road, and it is high likely to become unreachable until the municipal office in areas where predicted high seismic intensity by road blockage due to collapse of the roadside building. In these impairments complexed case, it became clearly that possibility of unreachable until the municipal office is increase, if section of road blockage is overlap with non-flooded section.

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 In order for a municipality to formulate disaster management plan on earthquake, damage estimation has to be carried out as the first stage. In the case that a city is formed on soft soil deposits like Kofu city, it is important to evaluate earthquake ground motion and ground strain in consideration of local site effect. Though it is known that local site effect of earthquake motions in alluvial soil deposits irregularly bounded by bedrock brings about local concentration of damage, the damage estimation by three-dimensional numerical analysis have not be conducted due to the restriction of computational resource. However, together with the development of computational science technology, large-scale analysis on three-dimensional nonlinear seismic ground response has become executable at the present time. Thus, local site effects, especially for local concentration of strain in surface soft soil deposits are examined in this paper. Seismic responses of an ideal alluvial soil model and the surface soil model for a part of Kofu basin are evaluated using three-dimensional nonlinear FEM analyses. The results of analyses imply the significance of three-dimensional nonlinear analyses of surface soil deposits in earthquake damage estimation.

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 A purpose of this study is to make a determination criteria whether the facility can be used or not and building the most suitable restoration scenario for damaged open-type pier after earthquakes. An experiment and numerical analyses were conducted to evaluate the influence of damage on a RC superstructure in a pier caused by an earthquake ground motion and a load in service after the earthquake which affects seismic performance during an aftershock. Then, we confirmed seismic behavior of an open-type pier that the RC superstructure has received damage due to main shock and load in service after earthquake by seismic response analyses of ground which consider soil-pile interaction. As the result, residual strength of the RC superstructure during the aftershock decreased with increase of the damage due to horizontal displacement and load in service. The results of analysis indicated that even if damage of the RC superstructure is considered, residual displacements of open-type pier do not change. Then maximum curvature at the upper part of the steel pipe piles increased, but change of the maximum curvature at the underground section was insignificant.

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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 as with general embankments. However, the detailed research of the special levees behavior induced by earthquake has not been promoted enough until now. In this study, in order to verify the applicability of the current design methods and investigate effective seismic measures for special levees, we conducted dynamic centrifuge experiments. Comparison between the designed and experimental values of the load acting on the seismic measures by soil improvement revealed problems in the current design method of the seismic measures.

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 When a number of ground motions having different characteristics are considered as candidates of design input motions, it is difficult to select or synthesize a representative wave among those waves. In order to avoid this problem, a scheme for clustering ground motions considering their effects on nonlinear structural response values has been proposed by the authors. In this paper, we verified the proposed schme through its application to a set of seismic records. Numerical results show that the scheme classifies seismics records according to their effects on a target structure.

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 As the lessons from severe damage of civil infrastructures due to Tsunami and ground motion in the 2011 Great East Japan Earthquake, “Anti-Catastrophe” concept can be a paradigm shift in structural / seismic design method. In a conventional design, seismic safety of a structural system is verified against “design” ground motion. But “Anti-Catastrophe” concept requests for structural designers to concern the possibility of catastrophic event caused by severe action unestimated in the design method. JRA Design Specifications for Highway Bridges was revised in 2012 and a principle similar to “Anti-Catastrophe” concept was adopted. In this paper, “Anti-Catastrophe” concept in the specifications is summirised and challenges are considered to produce effective measure in seismic design method based on the review of recent domestic and foreign trend of structural design.

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 Decomposing the earthquake motion phase into a linear delay part and a fluctuation part, we investigated stochastic characteristics in the discrete phase difference process of fluctuation part. Because the observed earthquake motion phase has the long memory with respect to the circular frequency and results in the self-affine similarity characteristic of phase difference process, it therefore must be expressed by a stochastic process with the fractal nature. Under the premise that the earthquake motion phase is calculated by summing up a discrete stochastic process of phase difference, we assume that the earthquake motion phase can be expressed by a Lubesgue-Stieltjes type integral equation in which the kernel covers a long memory characteristic of earthquake motion phase and the integration function expresses its stochastic characteristic. We also assume the identically independent distribution characteristic on the stochastic nature of integration function. If it has fixed variance and mean values, based on the requirement from the Central Limit Theorem, the proposed stochastic process of earthquake motion phase can express the variance and auto-correlation characteristics of observed earthquake motion phases but it cannot clearly express the all stochastic characteristics of observed earthquake motion phases. We therefore examine the necessary stochastic condition on the integral function.

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 The aging of numerous infrastructures that were constructed during the high economic growth period of Japan constitutes one of the current social issues. Additionally, irregular external excitations, such as earthquakes, cause damage to the structures, it thereby decreasing the original performance of structures and leading to changes in their natural frequency and damping characteristic. If these changes can be detected, it will be possible to evaluate the degree of aging of the structure, and enable health monitoring. The Fourier transform is one of the methods to detect the damage to the structure. However, the damage is dependent on the characteristic of the wave pattern. Moreover, the provided frequency characteristic has a limitation in that information is dependent on the time history at all times. In this study, we constructed the earthquake resistant design in accordance to specifications for highway bridges (2012 edition) for a single RC bridge pier and presented the M-Φ relationship for a specific pier base to allow the description of the M-θ relationship of the rocking SDOF model. Furthermore, we carried out a non-linear response analysis and performed the characteristic extraction of the acceleration wave pattern using the discrete wavelet transform and the wavelet spectrum. We concurrently examined the bending moment and the angle of rotation in consideration of aging with regard to the M-θ relationship and the vertical axis and the horizontal axis was examined whether detectable changes in the earthquake resistance by multiplying n. As a result of these analyses, decomposition coefficients estimated from the maximum value of the wavelet coefficients is increased owing to aging, and the frequency is confirmed to be reduced.

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 Port structures were damaged over a wide area of eastern Japan by the 2011 off the Pacific Coast of Tohoku earthquake. Though many damages of quay walls were due to liquefaction of ground, some damages were supposedly caused by tsunami action in addition to earthquake ground motion. Tie wire ruptured and collapse of steel sheet pile wall and aepron happened at the quay wall of Soma Port, possibly affected by the tsunami. Effective stress finite element analysis taking account of earthquake motion and subsequent tsunami under drained condition was conducted in this study, to clarify factors of the collapsed sheet pile type quay wall.
 As a result, it was found that damage of the sheet pile quay wall of Soma Port was light due to earthquake motion but was extended by subsequent tsunami action. Influence of tsunami action to the sheet pile quay wall was clarified with the analysis taking into account the tsunami water weight on the backfill ground; increase in residual water pressure as tsunami water weight on backfill ground more largely affected unstability of the sheet pile quay wall than vertical load acting on backfill ground surface as that.

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 In Kamishiro District, a residential area in Hakuba Village, serious damage of many wooden houses was caused by the 2014 Northern Nagano Prefecture Earthquake (M_J6.7). 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 2014 main shock with high accuracy by taking into account local site effects. In this study, we first estimated the seismic waveforms at 232 sites in the area. Next, we carried out 3-D DEM calculation of tombstone at 7 graveyard sites in the area, in order to confirm the applicability of the estimated waveforms. Based on the estimated waveforms, finally, we discussed the characteristics of ground motion which influenced the seismic damage of the wooden house. The estimated waveforms and obtained findings will be useful in future study on seismic performance evaluation of a wooden house.

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 During the 1993 Southwest Hokkaido Earthquake, not only strong motion but also huge tsunami is attacked in Aonae District, Okushiri Island, Japan. In this study, first, microtremor measurements with high density were carried out in the tsunami attack area. Seismic waveforms at sites of present strong motion station in the tsunami attack and non-attack area were then estimated based on the characterized source model considering site amplification and phase effects. Using non-evacuation time based on the time history of instrumental seismic intensity, finally, the effect of the strong motion attack on tsunami evacuation was discussed.

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 The 2011 off the Pacific coast of Tohoku Earthquake caused many damages due to liquefaction in residential areas of the Kanto Plane. After the earthquake, several countermeasures against liquefaction have been developed energetically; one of these countermeasures is an unsaturation method such as the microbubble water injection method by some researchers from our research group. During their developing process, there was no or few direct-confirmation technique of degree of saturation of a liquefaction layer in-situ, so it was difficult to quantitatively estimate effectiveness of liquefaction countermeasures. In this study, to develop estimation procedure of in-situ saturation degree for evaluation of an unsaturation method for liquefaction countermeasures, a series of simple tests by Piezo-Drive Cone Penetrator Tests called as PDC on un saturated model ground were carried out. As a results, different excess pore water responses between by a sensor inside the corn and around the unsaturated model ground were confrmed. The study suggests that application of PDC has enough possibiltiy to estimate saturation degree.

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 Tokyo Gas Co., Ltd. gathered approximately 60,000 borehole information, and the amplification factors of SI are installed in the real-time earthquake monitoring system, SUPREME. This study evaluated the site amplification characteristics using the ground motion records during the 2005 northwestern Chiba earthquake. The ground motion at the outcrop base was estimated based on a technique of strong motion prediction. The Fourier spectral ratio between the outcrop base and ground surface was compared with the transfer function of S-wave to investigate the accuracy of the geospatial data installed in SUPREME.

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 Great influence occurred for the city life including the slant of the house and the damage of the lifeline because of 2011 Tohoku Pacific coast off Earthquake in particular on the Chiba coastal line, and, above all, there was much number of the dam-age of the manhole. The authors established the application earthquake level of the construction method by performing the quantitative analysis by the laboratory shaking table tests about the upper part type and the homogeneous type in the self-weight increase method, and setting the allowable uplift quantity that were more appropriate by considering the function of the manhole in this study, and considering allowable maximum acceleration corresponding to this.
 As a result, the uplift restraint could hope the upper part type and the homogeneous type together, but, as for the upper part type, the rotation was big, on the other hand it found that the homogeneous type could restrain the uplift and the rotation equally. In addition, even if the homogeneous type, can apply on the earthquake vibration more than the maximum acceleration 800gal when it is loose, but as settlement after the liquefaction may occur in higher than greatest acceleration 200gal when it is very loose, it needs attention when the designer establish the margin of the safety factor in a design although it is possible enough for uplift restraint with uplift safety factor 1.0.

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 The quantitative case study on lifeline interrelation at actual earthquakes is few though there are several previous studies concerning the lifeline interrelation at an earthquake. This study attempts vitualizing the relation between lifelines during the Great East Japan earthquqake disaster, by counting the number of other lifeline-related words from the disaster reports on lifeline. As the result, the electric power supply strongly affected other lifelines, even if the accident at nuclear power plant is not considered. Next to the electric power supply, the transportation lifeline influenced much to the other lifelines in terms of facility damage and restoration activity. Moreover, the influence degree of the lifeline does not dependent on the report if it is on the same earthquake disaster.

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 This report summarizes road damage related to geotechnical problems caused by the 2015 Gorkha Earthquake, which were observed during a field survey conducted by a survey team dispatched by the Japan Society of Civil Engineers (JSCE) and Japan Geotechnical Society (JGS). In Kathmandu City, an embankment of the Araniko Highway, which connects Kathmandu to Bhaktapur, suffered from damage due to subsidence. Ground fissures, tilting of buildings and road pavement damage were also observed in the surrounding area. A microtremor measurement indicates small stiffness or thick soft soil layer at the heavily-damaged area. On the other hand, reinforced retaining walls demonstrated good performance against the earthquake. In mountainous areas, traces of medium scale landslides and rockfalls along roads were frequently observed. A large number of steep slopes failed at shallow depth in the epicentral area, and their scale in terms of quantity and size tends to increase as approaching the epicenter.

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 Seismic retrofit design of a steel cantilever bridge against Level 2 earthquake ground motions was performed by using seismic response control devices at piers and the central hinges, and continuing main girders at the central hinge sections. Three-dimensional non-linear dynamic time history analyses were carried out using earthquake ground motions specified in the current specifications for highway bridges, in order to improve seismic performance of the bridge. Dynamic performances were compared by changing the type and arrangement of the seismic response control devices. For installing seismic response control devices at piers or the central hinges, effects on seismic response reduction were confirmed, compared with the as-built bridge. It was found that continuing main girders at the central hinge sections and installing shear panel dampers at piers was effective with retrofit areas and retrofit members getting smaller. For installing shear panel dampers both at piers and the central hinges, more effects on seismic response reduction were confirmed.

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 Water distribution station is an important facility for storing drinking water which adjust to the time variation of the water supply. Underground distribution reservoirs are low-rise structures and often surrounded by six walls which are ceiling, side and floor. So the deformation suppressing effect is expected. Since tow-dimensional calculation is more simple and the result of the calculation is accurate compared to third-dimensional analysis, two-dimensional analysis model has been used as a standard for design in production level. When the shape of the lined up cross section is the same, accurate calculation result is obtainable using two-dimensional analysis. Although if the shape is complex, it is difficult to get the right result. The case study for large-scale reinforced underground concrete distribution reservoir which is divided in blocks and has a complex placement of seismic resistance walls has been studied. The case study comprises two analyses that are two-dimensional static analysis and three-dimensional static analysis which we compared and analyzed the both results. The result of the study tells us that the applicability of three-dimensional static analysis is reasonable. Also the result shows that it is difficult to simulate the structures accurately using two-dimensional static analysis and the cost of reinforcement works will be high. On the other hand the model analyzed using three-dimensional static was showed as a more reasonable design plan.

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 After an earthquake, MLIT conducts, road patrolling for the area of Japanese seismic intensity 4 or higher. However, when a mega earthquake occurred, there is a possibility that grasp of the damage takes more than several hours, and there is fear that quick disaster countermeasures becomes difficult. A real-time earthquake damage estimation system is set for disaster management of concerned facilities. The system is expected to support the decision making just after earthquakes and to outline scenarios of practical disaster drill. In case of development, it was based on an exchange of views with the person in charge in a disaster management section and was equipped with the function necessary to decision support of the time of an accident.

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 The 2014 northern part of Nagano prefecture earthquake of Mj6.7 revealed earthquake fault on the surface along the Kamishiro fault. Strong ground motions were generated near source area and caused severe damage to many houses. Authors performed damage investigation around source area in the aftermath of the earthquake. We confirmed a trace of the earthquake damage due to strong ground motion and ground displacement. We constructed a preliminary source model by the empirical Green's function method. The source parameters for strong motion generation area located on the fault plane were determined from the comparisons of the synthesized broad-band ground motions with the observed ones at several stations including near source. Resultantly, we proposed source model with one strong motion generation area located at near hypocenter. The relationship between seismic moment and short period level of acceleration source spectrum of this earthquake are expressed in a scaling law of the past study.

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 Strong motion due to the 2014 Northern Nagano Prefecture Earthquake (M_J 6.7) caused serious damage to wooden houses in Kamishiro District, Hakuba Village, Nagano Prefecture, Japan. In this study, first, microtremor measurements with high density were carried out at 232 sites in Kamishiro District. The ground shaking characteristics were then evaluated using the microtremor H/V spectra. Based on the empirical relationship between microtremor H/V spectrum and site amplification factor, finally, the site amplification factors from seismic bedrock to ground surface at 232 sites were evaluated. The evaluated site amplification factors will be useful in the strong motion estimation in Kamishiro District.

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 Experienced shear strain dependency of high damping rubber bearing which is induced by Mullins effect of rubber is one of the influential dependency to dynamic response of the bridge. So the effect of experienced shear strain dependency on seismic responce of isolation structure should be evaluated. From past studies, loading history must be taken into account to evaluate characteristics of high damping rubber. In this research, bi-linear double target model are investigated considering the experienced shear strain dependency. From seismic responce analysis, the effect of experienced shear strain dependency on seismic response was made clear. And proposed model was compared with normal bi-linear model.

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