We estimate the short-period spectral level A of the normal-faulting earthquakes in Hamadori, Fukushima prefecture in 2011 using the spectral inversion method. The A of M_J7.0(M_w6.6) earthquake is consistent with the average empirical relation between the seismic moment and A for crustal earthquakes. The PGA and PGV of this earthquake corrected by empirical site-amplification factor at each strong motion station agree with the average empirical attenuation relation for crustal earthquakes in Japan. The high area of the fault-normal to fault-parallel ratios of response spectra at 5 second of the normal-faulting earthquakes is longer than that of reverse-faulting earthquakes due to the domination of Rayleigh waves.

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This paper developed the new system for building damage assessment using photos of damaged house taken by residents or volunteer fire corps in damaged area. Specialists outside the damaged confirm these photos on the website and assess their damage levels. All the data used for building damage assessment is managed with GIS database on the management server located outside the damaged area under cloud condition. This kind of digital management system can contribute to enhance the accuracy, efficiency, objectivity and fairness of the procedures for issuing the Victim Certificates for residents. The system for uploading the photos of damaged houses was developed as mobile communication service. The remote system for specialists to assess the damage level was developed as web service. In this paper, the total system for supporting building damage assessment was developed and its prototype system was evaluated by local governments. Moreover, authors conducted feasibility study of developed system in damaged area as the 2011 off the Pacific coast of Tohoku Earthquake which examine communication speed to connect internet service by mobile phone.

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In order to calculate seismic intensity corresponding actual heavy damage to houses and buildings promptly, we tried to modify the filter used in the calculation of JMA seismic intensity. We modified the filter so that the calculated JMA seismic intensity corresponds to the actual heavy damage ratios of houses and buildings around the strong ground motion observation sites in the past earthquakes. We found that we could calculate the seismic intensity promptly by modifying the filter used in the calculation of JMA seismic intensity.

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A new prediction method for response spectra of earthquake ground motion is proposed. In this method the effects of rupture propagation on the source fault is evaluated theoretically by summing up the simplest waveform, named "Characterized Green's Function (CGF)", which satisfies the omega square model. The response spectra estimated by an existing attenuation equation is modified by the factor representing the effect of fault rupture propagation and radiation patterns, which is obtained on the basis of CGF. We verify the proposed method by comparing it with the results from the Stochastic Green's Function method in terms of a simple earthquake fault model. We also apply the proposed method to simulate the ground motions during the 2007 Niigataken Chuetsu-oki Earthquake. It is concluded from these comparison that the proposed method can estimate the response spectra of earthquake ground motion more stably and reasonably than the Stochastic Green's Function method.

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By using the seismic wave energy in surface layers calculated in the previous paper ¹⁾ based on vertical array records at 30 sites during 9 strong earthquakes, it is found that the upward energy decreases with decreasing ground depth in proportion to the power of 0.70 of the impedance ratio between layers. Based on this finding, the incident energies at the seismological bedrock were calculated from the energies at the deepest point of the arrays to correlate with corresponding hypocentral distances and seismic magnitudes.

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