Waveform inversion with empirical Green's functions was conducted for the foreshock of the 2004 southwest-off Kii Peninsula earthquake to reveal the slip and slip velocity distribution. Then, a pseudo point-source model was developed for the earthquake, based on the results of the waveform inversion. The pseudo point-source model can reproduce strong ground motions, not only at relatively near-source stations but also at remote stations as long as it is combined with an appropriate path effect model.

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Strong ground motion simulation was conducted for the 2005 Central Chiba Prefecture earthquake (M_J6.0) with the pseudo point-source model. For some sites where the site amplification factor was not available, it was newly evaluated by using past earthquake records at neighboring stations and microtremor measurements. Although the results showed generally good agreement with the observation, it was inferred that the model could be improved by considering directivity effect which was not included in the current model. At some stations, the peak frequency of Fourier spectrum was overestimated. The cause of the discrepancy should be revealed in the future study.

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We examined scaling laws of outer fault parameters of crustal earthquakes caused by normal faults, and obtained the same empirical relationship between the seismic moment and the fault area and that between the seismic moment and the short-period level as existing ones adopted by the Headquarters of Earthquake Research Promotion (2005). Furthermore, we estimated strong ground motions by the SGF method for a normal fault, which was set according to the proposed procedure. The PGA level of the resulting ground motions was similar to that for other types of faults. And the PGV level was similar to that for the strike-slip fault set according to the procedure by the Headquarters of Earthquake Research Promotion (2005), while it was smaller than that for the strike-slip fault set by Dan et al. (2011) or for the reverse fault set by Dan et al. (2015).

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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, we have presented a scheme for clustering ground motions considering their effects on nonlinear structural response values. Characteristics of ground motions are expressed using probability density functions (PDFs) of nonlinear response values of structural models and their dissimilarity is quantified by Jensen-Shannon divergence. As a clustering method, hierarchical clustering algorithm is applied. In this paper, for the purpose of verification, the proposed scheme is applied to a set of ground motions which are categorized into three types from the viewpoint of linear response spectra. When structural models are linear systems, the proposed scheme classifies those three types of ground motions. However, when nonlinear systems are used, it is found that clusters which are not in accord with their linear response spectra are formed.

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Concerning long-period component of the ground motions observed in various regions at the Central Chiba Pref. Earthquake in 2005; Mj6.0, we achieved the simulation analyses which were theoretically based on the wavenumber integration method assuming the point-source and the parallel-layered soil structure. There was the tendency that the ground motion orbit massively swelled up round in the horizontal plane at some observation points, which was adeptly explained by the superposition of calculation waves by two slip angles with determined independently, and it has been shown that the compatibility between the observed and the calculated waveforms are improved more than the simple source process model. Furthermore, we examined the quantitative variation by numerical computation that have to be assumed considering uncertainness of the ground motion due to the such complexity of slip angle at the earthquake-resistant design.

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Water supply facility is one of the important lifelines essential to human life. So, stable maintenance of water supply function at the time of major earthquake is strongly required socially. Many damages occurred in the water supply facilities by the 2011 off the Pacific coast of Tohoku Earthquake. Consequently, suspension of water supply lasted to a long term. And many of the water supply facilities were constructed during the high-growth era, or in 1960s and 1970s. From such a background, we have studied on the seismic response of large underground purification reservoir by three- dimensional dynamic analysis with the goal of improvement of accuracy and reliability of seismic performance verification method for water supply facilities. As a result, it has been cleared that the stresses induced by earthquake motion will concentrate on the portion of change of shape and rigidity of the structure, and the top of pillar within the purification reservoir. When the ground around the reservoir was softer than a hard case, the displacement by earthquake motion decreased, but the seismic stress by earthquake motion increased.

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A sliding mode control is one of control methods with superior robustness against structural parameter change and uncertainty of a model. However, a sliding mode control requires multiple control parameters and a design method of these parameters has not been established. In this study, we propose a design procedure to determine the control parameters so as to minimize the damage probability in a certain service period of a building. A semi-actively controlled base-isolated building is studied and the damage probability based on the proposed design procedure is compared with that based on a conventional procedure that determines parameters to minimize the response under design input ground motion with a certain level of intensity.

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This paper propose a method to estimate overall building responses during an earthquake using acceleration records from two seismographs those have single input-output relationship. At first, natural frequencies are found through frequency response function of top and basement records. Then, to obtain each modal response of top layer, band-pass filter is applied. Frequency ranges for band-pass filters are determined by middle points of adjacent points. Each story response is assumed to present by sum-up of each modal response with considering modal coefficient of each layer. To evaluate the accuracy of the method, the method was applied to existing building where responses of each layer have been recorded. The response estimation results substantially match the actual observations.

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Tensile loading tests of wood screw joint with steel plate and cross laminated were performed. There are two types of tests, the one is single joint shear test, and the other is multiple joint tensile test. The targets of the experiments are the effect of the grain direction and the effect of edge of the laminae which is not glued. The parameters for single joint tests are loading directions and material properties, and exist of border of layers. The parameters for multiple joint tests are loading directions and material properties. The loading protocols were monotonic loading, only tensile cyclic loading, and tensile and push cyclic loading. Two types of loading method were attempted on the single joint shear test: (a) Two steel plates were attached on the outer layers of CLT, and these plates are fixed each other, (b) One steel plate were attached on the one side of CLT, and CLT was not fixed. On the single joint shear test (a), brittle failure of screw occurred when the displacements were about 10 mm. The otherwise, the pulling out of screw and the shear failure of the outer lamina was observed on the single joint shear test (b). Tensile and push cyclic loading protocol gave negative effect on the deformation ability of the single joint connection. The exist of the border of layers didn't affected on the load displacement relationships.

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Impact of furniture turnover onto human during strong motion was evaluated with shaking table test. The authors carried out two kinds of experiments. The first one was carried out in January 2012 using shaking table and dummy doll. Five kinds of strong motions were tested for three situations and two kinds of floor surfaces. Acceleration at the head and deformation on the chest were observed on the dummy doll. The result varied much and the authors decided to carry second experiment. The second experiment was carried out in September 2012 at the long-stroke shaking table at the Building Research Institute, Tsukuba. In the test, the authors evaluated the effect of weight of the furniture, distance from the dummy doll, and initial angle to turnover. As a result, the authors got some relations between head acceleration and initial value of the furniture, and chest viscous criterion and velocity of the impact.

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In conducting damage assessment for scenario earthquakes in high seismic risk regions, building inventory data are required as well as building fragility functions and strong-motion distributions. But inventory data with the locations and characteristics of buildings are not so easy to construct, especially for developing countries. Hence in this study, an approach to construct building inventory data is sought as an alternative of cadastral data and field surveys. Using a high-resolution optical satellite image acquired by WorldView-2, this paper tries to develop building inventory data for earthquake damage assessment in Tacna, Peru. First, Pixel-based classification was carried out to examine basic land-cover and land-use of the urban area. Object-based building extraction was then conducted for three selected areas as an attempt to develop building inventory data.

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A new method to detect buildings washed away by a tsunami is proposed using high-resolution Synthetic Aperture Radar (TerraSAR-X) data. The main focus of this study is to integrate building unit based approach and zonal based approach to detect building damage at a building unit scale. These were integrated based on decision tree application (C4.5) of machine learning algorithm. Finally, classifier for detecting washed-away buildings was developed and applied to Sendai coast, performing 91.0 % overall accuracy and kappa statistic of 0.82.

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In order to detect the flood damage of flood or tsunami, we assessed quantitatively the flood damage by calculating water occupancy in each pixel of optical satellite imagery using Spectral Mixture Analysis (SMA). We applied the SMA for flood event in Bangkok, Thailand, 2011 and compared the result of SMA and visual interpretation from IKONOS image for accuracy velidation. Additionally, we developed an estimation model for calculating the water occupancy based on satellite SAR observation, comparing backscattering coefficients of the ALOS PALSAR image and the water fraction information derived from SMA method, which is applied to the Landsat-7 ETM+ reflectance image observing the 2011 Tohoku earthquake tsunami. By using our proposed formula and SAR imagery after water-induced disasters, we can perform to estimate flooded areas easily and quantitatively.

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This paper aims at developing a scheme to classify the local characteristic of disasters by earthquakes. First, we create the numeric indices which show the potential of the disasters. Second, conducting cluster analysis we classify typical areas in damage feature, such as Urayasu City hit by liquefaction due to 2011 Tohoku Earthquake, into seven characteristics. Finally, we classify other areas by conducting discrimination analysis to verify the method. We find that results derived from the method well classify overall damage situations due to earthquakes that hit in Japan during recent years.

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In Urayasu City, where about 85% of the city area liquefied during the 2011 Great East Japan Earthquake, water pipes were seriously damaged due to liquefaction. Joints of water pipes were pulled out at many sites. Shaking continued at a long predominant period for a long time after the occurrence of liquefaction during the earthquake. So, the long-period shaking of liquefied ground, which was a kind of sloshing must cause large cyclic compressional and tensile strain to the water pipes in horizontal direction near some boundaries, resulting in the disconnection of the pipe joints. Then seismic response analyses were carried out to demonstrate the concentration of horizontal tensile strain at 5 areas in Urayasu City under four levels of shear modulus by considering the effect of liquefaction. Analyzed results showed large tensile strain induced near the site where the water pipes were pulled out.

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By using the survey results in Sendai for the building vibration damages caused by the 2011 Tohoku earthquake (M9.0), we investigate the relationships between the strong-motion amplitudes and the damage ratios, which are classified by the structural types and the construction years. The following results are obtained: 1) Dependency of the damage ratios on the construction year is significant. 2) The obtained damage ratios for severe damages, especially to wooden buildings, generally agree with the fragility curves of Murao and Yamazaki (2002), Midorikawa et. al (2011), and Sakai et al. (2002). 3) By comparing with the survey results for the RC-building damages caused by the 1978 Miyagi-oki earthquake (M7.4), the damages for the 2011 earthquake, are heavy in Oroshi-machi, where the many old buildings are still used, while the damages are decreased for the 2011 earthquake in the other two areas, where the many new buildings have been constructed.

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Damage mechanism for buried pipelines of telecommunication systems subjected to the 2011 off the Pacific coast of Tohoku earthquake was clarified. Failure modes for 359 data were classified into 5 types. Relationships between the failure modes and indices of ground excitations such as peak ground acceleration, peak ground velocity and instrumental seismic intensity were revealed. The characteristics of damage ratio to reflect the differences in damage mechanisms of buried pipes affected by ground shakings and liquefaction were discussed.

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We performed benchmark tests for strong motion simulation methods using Stochastic Green's function method. The target event is the 2004 Kii-hanto-nanto-oki earthquake with M_JMA7.1. Strong motions observed at K-NET and KiK-net stations located in Kanto, Nobi, and Osaka planes are calculated under several analytical conditions. All the results calculated by participants generally show a good agreement to each other. The results are also compared to observed records, and the discrepancy of the response spectra is discussed. It is indicated that a priori information such as empirical site effects and observed phase data is important to improve the accuracy of the Stochastic Green's function method.

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