We study the relation between the energy index of seismic wave, named IED(Incident Energy Density), and earthquake damage of a structure by calculating the response of single-degree-of-freedom systems. The applicability of IED to the prediction of earthquake damage is evaluated by comparing relations between calculated response, such as ductility factor or plastic strain energy and indices for the intensity of seismic wave, such as IED, peak ground acceleration (PGA), peak ground velocity (PGV), instrumental seismic intensity, or spectrum intensity. In the result, it is obvious that IED is better correlated with ductility factor and plastic strain energy than other indices in case that yield seismic intensity is low and plasticity gradually progress. So, it is concluded that IED of seismic wave has applicability to the prediction of earthquake damage of structures.

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 This paper evaluates the seismic damage probabilistically. The target area of this study is Kumamoto urban road network. The procedures of this study are making the fragility curve, and then calculating indirect traffic damage based on fragility curve. Making the fragility curve includes three types of bridge pier. GUIDELINE FOR HIGHWAY BRIDGE SEISMIC DESIGN in 1972, SPECIFICATION FOR HIGHWAY BRIDGES Part V Seismic design in 1980 and 1990. To calculate traffic damage, it is considered scenario earthquake and the model of traffic assignment. Scenario earthquake is of Futagawa-Hinagu fault zone. The model of assignment is User Equilibrium Assignment. This study has yielded two results as the distribution of indirect traffic damage is normal, and there are 69 bridges in the area has failure probability, which are designed before 1980, and exist within 10km from the epicenter.

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 This paper reports the result of correlation analysis for house damage in 2007 Mid-piigata prefecture offshore earthquake by focusing geomorphological land classification and other factors as landform and ground properties with organizing the house damage data of disaster victim certificate conducted by public administrations. In former part of the paper, the features of house damage at 2007 Mid-Niigata prefecture offshore earthquake were analyzed for various influencing factors. The authors discussed the affrecting factors to houses at earthquake. In latter part, the features of house damage at 2007 Mid-Niigata prefecture offshore earthquake was discussed with that at 2004 Mid-Niigata prefecture earthquake. The house damage function of distance from the epicenter was proposed based on the analysis on house damage ratio recorded in two earthquakes.

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 In the seismic risk analysis of structures, information on seismic hazard and seismic fragility are required. Both hazard and fragility functions ( or curves ) are convolved numerically, and seismic risk ( or annual probability of failure ) of the structure is evaluated. In this paper, a simplified method for seismic risk evaluation is proposed, where information on the seismic hazard curve and the capacity of the structure are used and numerical integration is not required, and the seismic risk can be obtained graphically from the hazard curve. The proposed method is demonstrated using seismic hazard curves at two sites. Theoretical background of the method is considered from the closed form risk equation.

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 We develop a decision-making support system, so that the expressway company can take initial response quickly to earthquake disasters. We first developed a prototype system, which estimates the distribution of ground motion on the expressway covered, using the source parameters of the Earthquake Early Warning (EEW) and the empirical attenuation relations, and which maps the results on the geographical information system, Cyberjapan. The system was designed to perform adequately for major earthquakes, estimating the damages by involving ground motion waveforms as well as calculating by seismic parameters of EEW.

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 It is necessary to have an adequate fragility curves for highway embankments, with which we can consider the differences in the conditions of embankments. In this study, the damage to the embankment, based on the case histories in the Kan-estu and Hokuriku Expressway in the 2004 Mid Niigata Prefecture Earthquake, were classified based on the conditions of embankments. Based on the classfied data, the relationships between the level of seismic ground motion and damage ratio were investigated with the considerations in the difference of the conditions. And, the fragility curve for a standard section for expressway embankments was proposed.

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 This paper shows some reconstruction measures in damaged area by tsunami disaster from the 2011 off the Pacific coast of Tohoku Earthquake. Damaged areas may be categorized into several patterns considering location characteristics and land area, namely, small village available to move to high ground, large town not available to move and so on. Some measures such as construction of elevated roads or manmade fill are proposed considering refuge time and distance.

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 In the 2011 Off the Pacific Coast of Tohoku Earthquake, very huge damages of civil engineering structures etc. occurred by tsunami strikes along the rias coast and plane coast of the Pacific Ocean. For the urgent repair and the future reconstruction of these structures, the fundamental damage characteristics of these structures should be clarified by the field surveys from which effective lessons can be expected. In this paper, several important lessons on the resistance characteristics of 13 earth structures such as river dykes and sand banks which are obtained from the field surveys conducted by the authors are indicated.
 Because many dug pools were formed by the tsunami overflow at the backside of earth embankments and sea walls in this earthquake, the fundamental characteristics of the 10 dug pools are investigated thorough the field survey to estimate the effects of the dug pools quantitatively in the future. Furthermore through the field survey conducted at the representative site named Idoura, the scale and waterbed conditions of the natural canals and the strength characteristics of the river dykes and the base ground neighboring the natural canals are measured in detail and discussed.
 These fundamental lessons and data on the earth banks and dug pools will be able to be used to simulate the effects of the dug pools and to discuss the artificial canals as one of the hard countermeasures to reduce the tsunami height and/or force.

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 It is indispensable for passenger railways to prepare countermeasures against tsunami from the standpoint of both ensuring safety and maintaining public transport service that underpins the social life. In order to grasp the validity and limitation of the current measures, firstly, the examples of damages and responses in the field of railways in the case of some historical tsunamis and the tsunami caused by the 2010 Chile Earthquake as well as that caused by the 2011 Tohoku-Pacific Ocean Earthquake were surveyed. Secondly, elements of the complicated relevant legislations were put in order. Based on those steps, the details in the comprehensive measures against tsunami in the railways operation with the surrounding measures by the government and the municipalities, including the practices in the latest two tsunamis, were further analyzed by means of hearing as well as questionnaire survey conducted among many railway operators. The result indicated that there were some points to be improved in projection of inundation, passenger evacuation, acquiring tsunami information as well as communication and judgment in halting or restarting the operation of trains. Lastly, the desirable policies and technologies to be developed in the future in order to prepare for the possible East-Sea-Earthquake or Southeast-Sea & South-Sea Earthquake were extracted.

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 This study revealed tsunami forces to a bridge model using hydraulic experiments. Hydraulic experiments were conducted using a 1/100 scale plate girder bridge model with four main girders. The hydrodynamic forces acting on the bridge model were measured with a load cell, and the flow regime around the bridge model was observed using a high-speed camera. The results showed that the model suffered uplift force immediately after the tsunami action, which was followed by downward force. Further, the water level of upper stream side became high after the arrival of tsunami, because overhanging part of the girder reflected the wave.

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 The 2011 off the Pacific Coast of Tohoku earthquake tsunami caused the catastrophic damage of infrastructures such as coastal structures, utilities and transportation facilities. Among infrastructures evaluation of tsunami fluid force acting on a bridge deck is urgently required for designing a tsunami-proof bridge structure. Authors carried out hydraulic experiments by using high-speed camera to clarify the mechanism of horizontal and vertical wave forces acting on a bridge deck subjected to plunging breaker bores and surging breaker bores, focusing on the relationship between the position of a bridge deck against wave height and the occurrence of horizontal and vertical wave forces acting on a bridge deck.

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 It is necessary to study the precise pressure on a girder surface to clarify the tsunami action on bridges. This paper shows the pressure distribution and the mechanism of tsunami external force for the basic bridge section model from experiments. The mechanism of tsunami external force was estimated from the pressure distribution. The counterclockwise moment was generated on the bridge immediately after a tsunami action, because the negative pressure were induced on undersurface lower stream side of the model and the positive pressure were induced on the undersurface upper stream side.

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 A plan of tsunami hazard mitigation is discussed for a business establishment in the predicted inundation area of Nankai earthquake tsunami, based on a public hazard map. That is compared with the one based on a numerical simulation. It is difficult to obtaine the detailed inundation depth and arrival time from the public hazard map. Thus, effective countermeasure may not be taken by the business establishment. It results the large damage of the business establishment. On the contrary, the detailed information is obtained by using numerical simulation. It is possible for the business establishment to make an effective plan for hazard reduction. Thus, use of numerical simulation is effective for planning of tsunami hazard mitigation and business continuity planning.

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 We develop a method that converts elevation and building data stored in GIS (Geographic Information System) to a city model that can be applied to high resolution tsunami simulation using particle based numerical methods. We use DMD (Digital Mapping Data); a two-dimensional GIS data format as an input, and convert it to a city model constructed from particles. In order to use the two-dimensional GIS data as an input for a three-dimensional city model, we develop an algorithm to supplement elevation data stored in DMD. In order to demonstrate the usage of the city model, we develop a SPH (Smoothed Particle Hydrodynamics) code and apply it to the city model for tsunami simulation. In the results, building shapes are reflected properly in the numerical simulation, showing that the city model is applicable to tsunami simulation.

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 It is expected that the inundation induced by Tsunamis will damage the soil structure such as embankment. Estimation of the damage of soils structure such as embankment is important for disaster reduction. In the present paper, we have numerically studied the degradation of the ground due to Tusnami. As for the numerical method, we have used the liquefaction analysis method developed by one of the authors called "LIQCA". From the numerical results, it has been found that the degradation occur during the lowing of the water level, and the degree of degradation became larger with the higher maximum inundation level, the longer duration of wave or the more numbers of waves.

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 If tsunami hits, large-scale erosion or scour caused in various places. If the coastal scour by the first tsunami wave caused the destruction of a seawall, it is also considered that the second tsunami wave may generate much more serious damage. Therefore, research on a predicting method of the coastal erosion and scour by tsunami is important. In this research, a numerical model which can predict the coastal erosion and scour in a wide area including land as easily as possible has been built on the basis of Takahashi's et al model. Moreover, predicting methods of the maximum scour depth due to a back-flow and its position in the front beach of the seawall are also proposed.

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 Damage on road structures due to the ground excitation during the 2011 off the Pacific coast of Tohoku earthquake and tsunami is assessed based on the data provided by related Regional Development Bureaus, expressway sectors and local government sectors. We define a damage ratio R as the value of number of road damage points devided by total road lengths[km]. Maximum value of R for damage on road surface and road bump is 0.0224[point/km] in the range of seismic intensity 6.0 - 6.1.

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 We evaluate the dependency of damage and restoration of water supply systems and sewerage system on the seismic hazards in the 2011 off the Pacific Coast of Tohoku earthquake focusing on the damage at Ibaraki and Chiba prefectures. We use the damage data of the systems by carrying out field survey, interviews for related local government sectors and surveying the information in web sites. We quantify two damage ratios defined by the ratio of number of physical damage points N_p with the related pipeline lengths L and that of disrupted lengths L_d with L. In addition, we discuss relation between restoration periods with the seismic hazards. Finally, we verify the fitting of the damage data with previous seismic fragility curves on sewerage pipelines.

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 Damage on electric power failures at Ibaraki, Tochigi, Chiba, Saitama and Kanagawa prefectures and Tokyo Metropolitan government during the 2011 off the Pacific coast of Tohoku earthquake is analyzed. We collect the related data by surveying the information in web sites, and interviewing to the local government sectors and TEPCO branch office sectors by phone investigation. We quantify a damage ratio defined by the ratio of number of electric power failures with number of the related households, and the dependency of the index on induced seismic hazards due to the earthquake is revealed for subject cities.

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 In light of the recent disaster, a major theme for corporations is now how to go about disaster preparedness and business continuity undertakings. This survey examines the effectiveness of existing disaster preparedness and business continuity efforts, while also paying consideration to issues that must be overcome or improved in the future. This paper will present a path (requirements) for improving business continuity capacity, and endeavors to link that path to future assistance for recovery and business continuity for corporations by having the path utilized in developing various tools that ameliorate disaster preparedness and business continuity capacity.

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 During the 2011 off the Pacific coast of Tohoku Earthquake, Tohoku region suffered extensive damage by tsunami. The Tohoku region coast of the Pacific Ocean has been repeatedly damaged by tsunami in the past. Therefore, mitigation measures, such as highland transfer, education, construction of Tsunami protection wall, and training of evacuation have been taken by the government and the citizen. However, consciousness faded with the passage of time and same mistake was repeated. This report introduced the history of highland transfer carried out in affected areas and its effects on damage reduction due to the Tsunami. Also, it described the results of field survey and interview survey conducted with local residents of Ofunato and Toni from 26^th March to 1^th May 2011 by the authors.

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 On The Tohoku-chiho Taiheiyo-oki earthquake of March 11, 2011 with a very large magnitude of 9.0 caused the most disastrous tsunami and severe disaster along the Pacific coast in the Tohoku and Kanto region. Strong ground motion induced heavily damages over an extensive area in the East Japan. The earthquake induced widespread liquefaction not only in Tokyo bay area but also in inland area of Kanto region.
 For the purpose of recording earthquake damages, the authors carried out the reconnaissance of liquefaction damage in Saitama, Chiba Prefecture and the Tokyo Metropolis. As a result, severe liquefaction occurred at the reclaimed ground of the old river or the wetland in inland areas. Along the Tokyo bay area, liquefaction occurred in widespreading area of newly reclaimed land and caused severe damages to houses, road, life line facilities of electricity, gas, water supply, swage and so on.

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 The 2011 Touhoku-Pacific Ocean Earthquake caused severe liquefaction in a wide area of Kanto district. Many timber houses, buried pipes, roads, river dikes and port facilities were severely damaged due to liquefaction. Of them, serious damage to houses and lifelines occurred at Hinode area in Itako City, where a hosing lot had been constructed by filling a river. Many houses severely settled and tilted due to liquefaction. Then the authors collected the data on soil condition and settlement and inclination of houses, and studied the mechanism of the damage. Results show that a loose sand layer is deposited and ground water table is shallow. Though many houses suffered damage, the houses with pile foundations did not settle. On more remarkable thing is that the houses constructed on the ground by banking soil with 1 m high did not settle though surrounding houses settled.

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 The 2011 East-Japan Earthquake has caused sand-liquefaction over the long stretch of Tokyo Bay area. Both Konagai laboratory and Aero Asahi Corporation jointly surveyed Urayasu city, one of the heavily liquefied areas, to measure soil/structure subsidence caused by liquefaction. An airborne LIDAR imagery was obtained on April 20th and compared with that before the earthquake. To remove the effect of deepseated tectonic deformations, end-bearing pile supported buildings were taken as a reference. The first half of this paper verifies the accuracy of the map, and the latter half describes displacements that houses and coastal levees have suffered.

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 On April 11^th, 2011, Iwaki region of Fukushima prefecture was jolted by Fukushima-Prefecture Hamadoori Earthquake. Surface ruptures were observed along causative Idosawa and Yunotake normal faults. In addition to numerous small slope failures, a coherent landslide and building structures of Tabito Junior High School, bisected by Idosawa Fault, were found along the causative faults. A precise digital elevation model of the coherent landslide was obtained through the ground and air-born LiDAR surveys. The measurements of perimeters of the gymnasium building and the swimming pool of Tabito Junior High School have shown that ground undergoes a slow and steady/continual deformation.

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 A field survey of the 2011 Tohoku earthquake tsunami was conducted in Miyako city, Iwate prefecture. Tsunami height distribution and structural damages were discussed through survey results. The height of tsunami traces in Miyako ranged from 5-10 m of the inundation heights, 10-20 m of the runup heights. Although the flooded area of 2011 event is larger than the past tsunami events, the seawall along coastline worked the reduction effect of tsunami energy. Structures with reinforced concrete was no damage except for the case which drifting debris collided with structures. Also steel structures was no damage as long as a tsunami height does not exceed the height of structure.

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 Damage on road structures due to the 2011 off the Pacific coast of Tohoku earthquake and tsunami is assessed based on the data provided by related Regional Development Bureaus, expressway sectors and local government sectors. We define two damage ratios R_L^r, R_N^b as the value of number of road damage points devided by total road length[km] and that of number of bridge damage points devided by total number of bridges subjected to the tsunami. Maximum value of R_L^r is 2.12[point/km] at Otanigawa Ishinomaki City, Miyagi Prefecture and Yagawahama Ishinomaki City, Miyagi Prefecture, and that of R_N^b is 1.0 at Minami-sanriku Town, Miyagi Prefecture(Utatsu Long-bridge).

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 On March 11^th, 2011, Minami-Sanriku, located in the northeastern coast of Japan was severely inundated by the tsunami that followed the Great East Japan Earthquake on March 11, 2011. Road bridges near the coastlines in this area have been extensively damaged with their decks being overturned or carried over long distances. An attempt was made to deduce as rational scenarios as possible before remaining debris was cleaned up. Though the reasons for the washout of bridges can be many and complex, it is to be noted that bridge decks have hollows for the optimum light-weight solution, which fact eventually allowed the bridge decks to be carried over remarkable distances. Poor connection details and cavities, hollows between deck beams, are considered to have facilitated overturning due to uplift forces.

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 This paper describes the damage assessment on road structures due to the slope failures in the 2011 off the Pacific coast of Tohoku Earthquake. We classified the failure modes for the 43 database on the damage of road structures due to the slope failures and analyzed them from the view point of the peak ground acceleration, the peak ground velocity and the seismic intencity. In addition, damage functions on the failures of the road structures due to the slope failures in the 2008 Iwate-Miyagi Nairiku Earthquake are verified by comparing the derived results from this study with the values from the functions.

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 There were the following typos in the article, "Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)) Vol. 68 (2012) , No. 4 (JSCE Journal of Earthquake Engineering, Vol. 31-b), pp. I_365-I_382"

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