It is necessary to evaluate site amplification factor due to deep subsurface profiles for the precise evaluation of input earthquake ground motion. Spectral inversion analysis is applicable to evaluate amplification factor at strong motion observation sites. However, other method is required for sites without strong motion observation. The present paper discusses a simple estimation method of amplification factor for sites with thin sedimentary layer according to the microtremor H/V spectrum. The proposed method uses both statistical amplification factor of low frequency and amplification factor due to sedimentary layer.

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This paper deals with estimation of a site effect of local government observation sites. We have already proposed the method to evaluate site effect by using PGA and JMA seismic intensity obtained at local government observation site because it is difficult to obtain waveform records there. This method can be accurately evaluate an averaged amplification factor of site effect in arbitrary range of period from 0.1 to 1second, but not accurately evaluate it between 1 and 2 second. In this study, peak acceleration ratio related to relative amplitude of earthquake spectrum in this period range was considered in evaluation in order to improve the accuracy of evaluation of the site effect in this period range. The correlation between peak acceleration ratios calculated from records observed in earthquakes of about magnitude 7 and the site effect in this period range was estimated. Since both have a good correlation, site effects were evaluated by formula in terms of amplification factors and peak acceleration ratio. As a result, correlation between observed site effect and evaluated one in this period range was improved, and its correlation coefficient were more than 0.9 in almost all period range.

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This study examines dependency of amplification factor on earthquake magnitude based on a relation between spectrum of earthquake motion and site amplification factor derived by Parseval's theorem and extreme value theory. Amplification factor evaluated from a formula proposed here, and one estimated from artificial wave have a good agreement in their comparison. We represented amplification factor by using corner frequency fc and cut off frequency fmax to examine influence of fc and fmax to amplification factor. It is clarified that influence of fc for PGV is larger than that for PGA and influence of fmax clearly affects for PGA but less for PGV. Relationship between moment magnitude Mw and amplification factor is also estimated. Mw is seemed to affect an amplification factor for PGV rather than that for PGA.

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Microtremor observations were carried out to determine the subsurface structures of the Padang City, Indonesia. Serious damages occurred by the strong ground motions during the 2009 Southern Sumatra earthquake in the area. The S-wave velocity structure models at the 12 sites were determined from array observation records. The predominant period at 60 sites were obtained from 3-componet observation records. The S-wave velocities of alluvial layers were 80-300m/s. The predominant period was 1.5-3.0 period that H/V spectral ratio has clear single peak models along the coast line area. It was found that soft alluvial layer was distributed whole area from S-wave velocity structure. Depth to bedrock (S-wave velocity is 500m/s layer) was about 100m maximum in the area.

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Near-source velocity pulses often have significant effects on the performance of structures. After the 1995 Hyogo-ken Nanbu, Japan, earthquake, it has been recognized that the velocity pulses are caused by forward directivity effects and can be simulated accurately by using characterized source models. During the 2007 Chuetsu-oki, Niigata, Japan, earthquake, however, large-amplitude near-source velocity pulses were observed at sites without forward directivity. In this study, applicability of characterized source models for this type of velocity pulses are investigated. As a result, it was found that a source model with considerably small asperities is required to represent the velocity pulses.

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In order to establish a seismic design method, an analytical study was conducted on the influence of boundary conditions at the base of composite ground formed around piles to increase their horizontal resistance in soft ground. The results of a series of two-dimensional nonlinear finite element analysis confirmed that pile displacement was reduced by 25 to 30% and seismic performance was improved under Level 1 and 2 seismic motion due to the constraint effect of composite ground around piles (similar to the results of static loading). While the basic depth for improvement in composite ground is the characteristic pile length (1/ ), it was verified that an N value of 15 or larger for sandy soil and 8 to 10 for cohesive soil was necessary as a base condition for composite ground to ensure the adaptability of the ultimate earthquake resistance method and the mitigation of pile deformation during earthquakes.

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Apparent velocity of seismic waves traveling along a shield tunnel at Tokyo International Airport was evaluated based on observation of acceleration and relative axial displacement between segment rings during 13 earthquakes with magnitudes ranging from 5.3 ? 8.0. As a result, it was made clear that the apparent velocity depends not only on frequency but also on the incident angle of seismic waves. The apparent velocity decreases with the increasing incident angle, probably because of surface wave generation. The calculation error of peak relative displacement can be reduced by 45 % if the dependence of the apparent velocity on the incident angle is taken into account.

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Dynamic earthquake response of subsurface ground, with spatially varied shear modulus was examined with the aid of Monte-Calro simulation. Through the series of simulations, it turned out that spatially varied soil property does not necessarily cause variable dynamic responses. Dynamic response of ground is dominated by 1st vibration mode, which means the ground motion is controlled by 1st eigen frequency. As long as 1st eigen frequency is not variable, even though the shear modulus varies spatially, the dynamic response cannot be variable. Besides, it was shown that Monte-Carlo simulation results distributes around deterministic analysis results carried out with uniformly changed shear modulus, and that deterministic analysis results can be utilized to estimate probabilistic behavior of dynamic earthquake response of subsurface ground with spatially varied shear modulus.

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Major liquefaction and consequent lateral ground flow of the ground may occur at the reclaimed lands during the expected great earthquake smashes the highly populated bay areas of Japan along the Pacific ocean, because of poor in liquefaction countermeasures so far. Thus, preservation of the seismic safety of the reclaimed lands, at which major industries are concentrated, is the most important issue. Basing on this background, this research focuses on the development of the countermeasures against liquefaction induced lateral flow of the reclaimed land efficiently and economically. For this purpose, centrifuge experiments were conducted to compare the efficiency of the countermeasures, to which the sheet pile wall method, the ground compaction method and the deterrent pile method were adopted. In addition, basing on the test results, evaluation methods, which may be utilized as the design method, for the flow force of the liquefied ground acting on the countermeasure were estimated.

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PML(Perfectly matched layer), especially convolution PML is known to have high capability of wave absorption. Unfortunately, it is not possible to input earthquake waves through PML, contrary to viscous damper. A method to inject seismic waves to FEM domain enclosed by convolution PML is proposed. By comparing the numerical results by this method with those by conventional methods, the validity of the proposed method is shown. The effect of each PML parameter is also clarified. Next, convolution PML is applied to long model in numerical simulation of surface wave and its superiority over conventional PML and viscous boundary is demonstrated by numerical results.

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Since seismic-isolation foundations generate relatively large displacements adversely affecting the running safety of train during earthquakes, it is an important task to assess this influence and to develop a new type isolation foundation that can secure the running safety of train. In this paper the authors have proposed a seismic-isolation foundation that can convert the response displacement in the lateral direction of track to the longitudinal direction that has less effect to the running safety of train. This new type isolation foundation is composed of FPS (Friction Pendulum System) slider, concave plate and guide ditch. To confirm the behaviors of the proposed isolation foundation, model experiments were conducted under statically and dynamically loading. Moreover, 3-D numerical simulation, which can take the geometrical nonlinearity into account, was applied to explain the situation of the model experiments and real structures installed the foundation. As a result, it is verified that the proposed foundation can keep both the effects of the seismic-isolation and the running safety of train.

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The earthquake motions have been observed near the earthquake source faults because of increasing of strong motion instrument stations. Some of the earthquake motions have the predominant waves in the range of high frequencies which are higher than around 10Hz. In this paper, the effects of the earthquake motions with a predomionance in the high frequencies on dams were evaluated. Dynamic 2D-FE analyses of dams were carried out using the simulated motions and the observed earthquake motion with a predominance in the high frequencies. Analytical methods considering earthquake damage process were used; nonlinear analysis with a smeared crack model for concrete gravity dams and the combination of equivalent linear analysis and Newmark sliding block analysis for rockfill dams. The results of the analyses revealed that input earthquake motions with a predominance in the high frequencies have littlle severe effect on seismic performance as maintaining of water storage functions of dams. However, in the case of concrete gravity dams with an over 50m high, it is noted that effects of high frequency input motions cause a little tension crack progress restricted within the upper part of the dam body near the top.

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The seismic behaviors of the deformed pipelines are not clear. The effectiveness of the flexible and nondetached mechanical joint is not examined enough. Moreover, the influence of the joint characteristics on the bending moment, stress, strain of pipelines, etc. has not been clarified. Numerical response analyses were carried out for buried pipelines with typical joint characteristics and soil frictions subjected to seismic waves by using ERUAL program. As a result, it was found that the stress concentrations occur near bend pipe section or branched pipe section as the bending moment and the rotation are predominant, and the effectiveness of the flexible and non-detached mechanical joint (S-MD joint) was verified.

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In this study, elasto-plastic finite displacement analysis using shell element was conducted to clarify the extremely low cycle fatigue crack (ductile crack) initiation and final failure mode in thick walled steel structures with welding defect. This analysis was based on the cyclic loading experiment of beam-column connection specimens with welding defect in the butt flange joint which must be full penetration welding under the earthquake motion. These specimens were faithfully manufactured based on actual structural details and welding method. As a result of the analysis, extremely low fatigue cycle crack initiation was accurately estimated in cases that crack origin is in flange plate around the fillet of column. But it is difficult to estimate the extremely low cycle fatigue crack initiation, if crack origin is in the root of welding defect in the butt flange joint.

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This study presents an investigation on the response of polypropylene fiber reinforced cement composites to uniaxial compression, tension and cyclic loading. A series of experiments were conducted on specimens 350 mm high with cross-section of 105 mm by 70 mm tapering to 70 mm by 70 mm at the center. The effects of cyclic loading on the stress-strain envelope including unloading and reloading paths in both compression and tension were examined. It is found that unloading and reloading do not essentially change the shape of the stress-strain envelope. Reverse cyclic loading affects the tensile response of the material if the uniaxial compressive strength during loading was exceeded and not to affect the tensile response if the compressive strength was not exceeded.

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This study proposes a method of combining microtremor measurements and simple ground modeling. From microtremor measurements conducted on a ground surface, H/V spectral ratios are calculated. Then, a multi-layered soil deposit is replaced with an equivalent homogeneous ground underlain by bedrock. Showing that the simple ground model is suitable to be used in a low frequency range, the ground is attributed to further simplified ground model. Similar computational results are obtained for eigen analysis of multi-layered, irregularly bounded ground between the proposed method and three dimensional finite element method.

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The purpose of this research is to investigate influences of plate thickenss on low cycle fatigue strength at weld toes of cruciform welded joints. The influences of plate thickness ranging from 25mm to 40mm on low cycle fatigue strength were investigated by bending fatigue tests under large plastic strain on cruciform welded joints, and its elasto-plastic FEM analyses. It was found that low cycle fatigue strength decrease with increasing of plate thickness due to increases of local strain at weld toes by increasing plate thickenss. Moreover, the decreases of low cycle fatigue strength were evaluated based on increases of local strain at weld toes obtained from elasto-plastic FEM analyses.

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In the current seismic design, only earthquake shaking is considered and the influence of fault displacement is not considered. However, since linear underground structure such as tunnels have a possibility to be constructed across faults, they have a probability to get severe damage due to the fault displacement. In this study, seismic performance of a tunnel that crosses a fault and the effectiveness of an isolation measure using polymer material is investigated through the three-dimensional static finite element method.

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In order to ensure sufficient bridge seismic performance, various types of elastomeric isolation bearings have been adopted to the seimic isolation bridges. Even if energy absorption capability of the seismic isolation bearings is taken into account, excessive displacement of bridge girders is inevitable. It causes high constraction cost and maintenance problems . The main objective of this study is the use of the tuned mass dampers (TMD) installed to bridge girders supported by elastomeric isolation bearings to circumvent this problem.The second objective is to calculate the tuning condition of the TMD in order to take nonlinealiry of elastomeric isolation bearings into account. Effectiveness of the TMD installation is discussed based on numerical simulation of the dynamic response, and it is shown that the girder response can be reduced to less than 50% of the original case if the mass ratio of 0.1 is allowed.

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When loading tests are conducted on steal or reinforced concrete members with elasto-plastic behavior, the tangent stiffness is often of great interest focused. Especially, in the loading test of multiple loading points or controlling many degrees of freedom, it is used as the characteristic value to indicate elastoplastic behavior of the test specimen or as information to achieve higher accuracy in controlling loading actuators. The minimal update approach is used as the estimation method for the tangent stiffness matrix, which is an extended concept of the tangent stiffness in multi-degree-of-freedom systems. The stability and reliability of the method are studied with structural models with simplified bilinear restoring force property.

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Generally, the underground is thought to be safer than the ground, because the acceleration amplitudes of earthquake motions tend to be smaller in the underground. However, it is considered that the seismic safety of structures will largely affected by the mutual effects between the ground structure and the underground structure during earthquakes. Then, we made 3-D dynamic analyses regarding the coupled subway - underground shopping arcade - high building system in order to evaluate the effects of earthquake behaviors of high buildings on the underground shopping arcade. As a result, it is considered that the high buildings will behave out of phase with each other, and that the dynamic stresses around the connecting parts between the underground shopping arcade and the high buildings will be largely changed by the displacement behaviors of high buildings. In order to realize earthquake disaster prevention in urban area, mutual effects between the underground structures and the ground structures shall be taken into account.

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Stiffener strengthening technique, adding additional stiffeners and strengthening flange plates, is adopted to enhance ductility and buckling strength of existing stiffened plate in an existing steel bridge pier. However, in this technique, the additional stiffeners are welded and the flange plates are bolted. That is, quality assurance of the welded part and workability in a narrow space in the steel bridge pier are to be improved to suggest more economical and rational strengthening technique for retrofitting the existing stiffened plate. Then focused on in this study is a strengthening technique using L-shaped strengthening member joined with high strengthening bolts to the plate panel between the existing stiffeners. The effectiveness of this technique against cyclic load is investigated through cyclic loading test. It is concluded that the L-shaped and bolted stiffener effectively works in changing the buckling mode of the plate panel and shows a sound strengthening effect as in the case of the welded stiffeners.

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In this study, detection method of damage existence and localization using an actuator which can excite structures at high frequencies is proposed. The method is based on the fact that the vibration properties at high frequencies are sensitive to small damage. Change in Fourier amplitude at the excitation frequency is used as the damage indicator. Through theoretical, experimental and numerical investigations, it is found that the change in the Fourier amplitudes is large if the damage is located at the crest of vibration wave shape. Therefore, by exciting the structure with various frequencies, damage existence can be detected if the Fourier amplitudes changes at some frequencies. Moreover, damage can be located by choosing the point which becomes the crest of vibration wave shape for the frequencies at which the Fourier amplitudes changes largely.

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Seismic behavior of gravity type quay walls with ground anchor for seismic reinforcement is not clarified enough, because few case study of seismic behavior of gravity type quay walls with ground anchor for seismic reinforcement has been conducted. In this study, we conducted shaking table test about caisson type quay wall with ground anchor for seismic reinforcement and evaluated relation between the deformation of caisson type quay wall and the tension of ground anchors. And we calculated safety factor of sliding, rotation, bearing capacity, based on result of shaking table test, because we researched relation between safety factor and deformation mode of caisson type quay walls.

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The purpose of this paper is clarify the seismic response characteristics of small irrigation earth dams on the basis of the observation immediately after an earthquake swarm beginning from December 17, 2009 in the region of off the east of Izu peninsula. We performed a two-day earthquake observation simultaneously on two valley-type irrigation dams, placing three sets of three-component microtremor sensors on the crest of the two dams and on the outcropping firm ground, immediately after the beginning of the earthquake swarm. The results of analyses on seven small and micro-earthquke records revealed that the horizontal dynamic response characteristics of the dam crest identical to each other.

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Retrofitting of low earthquake-resistant houses is a key issue for disaster mitigation. In this research, we developed an educational tool learning from structural damage photos taken after the past earthquakes. About 300 house owners accessed its website and learned by themselves. The effectiveness of learning was evaluated by questionnaires just before and after the learning and seismic diagnosis. The number of house owners who wished to conduct retrofitting and seismic diagnosis increased after learning and effectiveness of learning was verified.

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An industrial water pipeline has several customers who will make severe demand on water supply conditions based on the Business Continuity Planning (BCP) requirement. Especially, a deteriorated pipeline which cannot maintain the seismic safety condition should prepare immediate retrofitting plan to comply with the BCP requirement. This study proposes a certain measure for decision-making associated with the seismic retrofitting investment strategy preventing a large-scale malfunction such as industrial water supply stop under seismic risk. Newly developed stochastic value index is adopted for the overall evaluation of social benefit, income, life-cycle costs and failure compensation associated with the existing industrial water pipeline system damaged by an earthquake during the remaining service period. Discussions are given for the opti-mal seismic disaster prevention investment of the existing deteriorated pipeline system. Finally, the present study can provide a performance-based design method for seismic retrofit strategies of existing pipeline which can be carried out through the target prob-abilities of value loss and structural failure.

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In recent years, the simulation systems of emergency evacuation have been developed. It is required for the practical use to verify the systems by comparing the results of the simulation with the actual human behavior in an emergency. On the other hand, in the practical use, building the analytical model is complex and it takes much labor. This may be the biggest factor which avoids the progress of the simulation of emergency evacuation. In this study, the system to develop the automatic building of the analytical model for the evacuation simulation using the numerical maps is introduced. An example of simulation by Cellular Automata (CA) is demonstrated with the proposed system.

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The disaster response management system is an information system supporting local governments with disaster responses. The prototype system has been operated in Mitsuke City, Niigata prefecture for 3 years and was applied to the actual disaster response during the typhoon No.18 in 2009. It was extended to two other local governments in Yamanashi prefecture and the process to build disaster response management systems for the two local governments by making a modification on Mitsuke's system was stated in this paper. New functions to coordinate the disaster response management system with other information systems were developed. One was the coordination with the regional social networking service (SNS) and the other was the coordination with the triage management system in a hospital. These functional expansions were summarized in this paper.

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In the airport where various facilities are installed, it is feared that their function will be suspended when the ground in airport site is liquefied by large earthquake. Especially, runway pavement which performance needs bearing capacity and keeping allowable surface deformation after earthquake, will be damaged such as differential settlements with deformation of the ground induced by liquefaction. In this case, it is thought that there is a possibility to stop the present serviceability of runway even if damage to runway pavement structure is locally caused by liquefaction. This paper describes investigations to estimate damages to runway pavement ground induced by liquefaction using geophysical exploration which were used as a technique for an interpolation of the existing geological information.

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In order to carry out existing earthquake-proof assessment of wooden house based on the Limit Strength Evaluation, it is necessary to estimate the ratio of site amplification of ground. In this research, we developed the estimation table of the ratio of site amplification of ground. This table is made based on the result of nonlinear response analysis of over 3,000 bore hole data in Kobe city. It becomes possible to estimate the ratio of site amplification of ground in which the property of ground, period characteristics and input motion are considered, easily.

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Water supply system is one of the most important infrastructures as a key lifeline which supplies tap water for drinking and city activities. Even if incase of disaster, it has a important mission such as emergency water supply and supplying water for fire-fighting and medical use. On the other hand, there are several risks such as Tonankai-Nankai earthquakes. Restarting water treatment as soon as possible contributes to minimizing social influence of disaster. Such a situation is considered, we estimate the influence on water treatment by seismic motion, and discuss the recovery strategy from the view point of Business Continuity Plan.

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This paper aims to show the function of emergency road networks after an earthquake in perspective of local assistance for the restoration process of lifeline systems such as electric power supply systems, gas supply systems and telecommunication networks. For the analysis, the earthquake in Tokyo metropolitan area and the following assistance from related facilities with above lifeline systems in the Kanto area are assumed. We employ three indexes to quantify physical and functional state of the road networks to be used during post-earthquake restoration process: distance exposure for seismic intensity, congestion level and predicted traveling time based on the traffic census.

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This study investigated aged deterioration of tensile and shear strength of adhesive bond used for seismic reinforcement of tombstones. First, accelerated weathering test was conducted in order to make test specimen of 5, 10, 20, 30 years old in addition to test specimen of 0 year old. Then, uniaxial tensile test and cyclic shear test was conducted in order to measure the tensile and shear strength characteristics. It was found that the tensile strength became smaller as the test specimen becomes older after 5 years. The shear strength was almost the same among the test specimen of 0, 1 and 20 years old. Finally, seismic simulation of tombstones with different bonding area and different age is conducted. There is a tendency that the tombstone with larger bonding area and with younger age are less likely to overturn.

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In the 3-dimensional distinct element method (DEM), equations of translational and rotational motions have to be solved. In this paper, a new time integration scheme for the rotational equation of motion based on the leap-frog method is proposed. The proposed method does not need assuming initial values or iterative calculations which is required for the previous proposed leap-frog-based scheme. A free vibration responses of an elastic masonry wall are computed using three time integration schemes, namely, the Euler scheme, previously proposed leap-frog-based scheme and the proposed scheme in order to confirm the validity of the proposed scheme. The validity is also confirmed by comparing the results with those by the finite element method (FEM). Vibration responses computed by the proposed scheme shows good agreement with those by the FEM. It is verified that the proposed scheme is superior to two schemes in the stability, time efficiency and accuracy.

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A shake table test of a large model is conducted in order to understand the deformation of the breakwater in the earthquake because the breakwater based on replaced sand will deform greatly by soil liquefaction. As a result, the settlement of the breakwater increases greatly with the rise of the excess pore water pressure in the foundation ground. And it is confirmed that the foundation ground moves so that it is pushed out from the caisson under to the outside. Moreover, an effective stress analysis is conducted in order to confirm the reproducibility of the experiment. The deformation of the foundation ground and rubble mound show good agreement with that of the experiment.

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The average percentage of earthquake resistance of water distribution main pipe is about 12, so it is said to be necessary to proceed in earthquake resistance, but in process, financing the budget by raising water fare and so on is postulated. The relationship between coseismic damage of water suspension and defrayment of water fare is social dilemma, so it is necessary to decide the level of earthquake resistance by fostering risk commincation between a water supplier and comsumers. In this study, we surveyed cosumers' willingness to pay to enhancing earthquake resistance by adapting CAUSE model which is one of the way of risk communication. Thus, their willingness in CAUSE model is higher than in public relation that water suppliers already have.

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The paper focuses on damage to lifeline facilities subjected to Tsunami. Tsunami will hit the wide areas between Kii peninsula and the coast of Shikoku if the Tohnankai and Tohkai Earthquakes happen. The precedents of damage to lifeline in the recent earthquakes do not exist because the large tsunami did not occur in the recent earthquakes around Japan. We firstly focus on the damage to lifeline facilities due to flood tide and high wave occurred in Japan and clarify the characteristics of the damage by flood. Then the damage caused by the 2009 South of Samoa Islands Earthquake and tsunami is investigated through reconnaissance work. Finally we study the characteristics of damage to lifeline facilities subjected to tsunami and its counter measures.

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This paper presents the results of field survey conducted by the authors after the 2010 Chile earthquake. The authors visited the affected area about a month after the earthquake occurrence. The GIS datasets for building damages in Talca and tsunami inundation areas are constructed in this study and a series of fundamental analyses are performed using the digital elevation model (DEM). In addition to that, the availability of satellite images captured after the earthquake to detect damaged buildings in Talca is discussed using the GIS data constructed in this study.

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This paper introduces damage of bridges due to Offshore Maule earthquake (M=8.8) on February 27, 2010, in Chile. Authors involved in the reconnaissance group member of JSCE and investigated 46 bridges at 31 sites located in between Santiago and Concepcion. Damaged bridges were mostly simplesupported pretension PC girder without the crossbeams. Such structure system was proposed in terms of the cost reduction and shortening of construction period, which might result in the intensive damage including the unseating of the decks. It would be also remarkable that the rubber bearing unfixed to girder/column might result in extreme movement in the transversal direction during the seismic excitation, which caused deck rotation in the skew bridge. Furthermore, subsidence of substructures was observed in bridges built on the liquefable soil condition.

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It is important that making the water service pipeline earthquake-proof provide the priority level. It is in the situation to which the water-supply corporation is worrying about the judgment of so-called'Good the ground' intended for the underground water service pipeline. This paper focuses on earthquakeproof adaptability of ductile cast iron pipe with K-type joint. The relation between the damage during the recent severe earthquakes and ground condition was examined. The ground condition that earthquake-proof adaptability of ductile cast iron pipe with K-type joint is recognized was clarified.

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The paper is focusing on the effect of countermeasures for subsidence of houses due to earthquake. Residential land of high embankment in Nagaoka New Town was suffered severe damage in the 2004 Niigata-ken Chuetsu Earthquake. Many houses were damaged by subsidence of residential land induced by soil liquefaction. Countermeasures for subsidence of houses were done after the earthquake. Reliquefaction occurred at the same areas in the 2007 Niigata-ken Chuetsu-oki Earthquake. The detailed survey for the residential land and damage to houses were conducted after the earthquake and the effects of the countermeasures were discussed.

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This study developed the house damage data-base of Mid-Niigata prefecture earthquake on Geographical Information System (GIS) and investigated the correlation between house damage and geomorphological land classifications. It is noted that the damage ratio of house was accurately assessed through GIS by using both house damage data-base and house data-base. Consequently, house hazard could be objectively discussed against the geomorphological land classification. It was concluded that house hazard generally decreased with distance from the earthquake epicenter, but it kept high in alluvial fan. The property of house damage distribution was keenly discussed quantitatively with various indexes.

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In this paper, a countermeasure by means of installing a fairing on the side of superstructure of bridge was proposed with the purpose of establishing a method for reducing tsunami effects on highway bridges. A series of hydraulic flume tests taking into account of twenty kinds of fairing shapes and two kinds of tsunami wave heights were conducted for investigating the influence of fairing shapes on reduction effect on tsunami wave forces. It can be concluded from the discussions that reduction effect on tsunami wave forces is influenced by the fairing shape and a fairing with rational shape can provide a good reduction effect on horizontal wave force.

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