The fill ground has higher risk of seismic damages comparing to the cut ground. However, few attempts have been made so far to measure actual seismic responses and to investigate the difference of seismic responses between the fill ground and the cut ground. Accumulation of basic observation data is required for evaluating the fill slope stability against the earthquake. Authors performed in-situ array seismic observation in the fill ground and the cut ground for two years. Four seismographs, a rain gauge, a water table gauge and two soil moisture sensors are installed in this observation area. This paper shows differences of seismic responses between the fill ground and the cut ground. And influences of the soil moisture to the seismic responses are studied.

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We carried out damage investigation around the seismic stations where high JMA seismic intensity scales were recorded in the 2008 Iwate-Miyagi-Nairiku Earthquake. We found some minor damage such as small cracks in the wall or damaged roofs, but heavy damage to buildings was not found around all the seismic stations. We investigated the correspondence of strong ground motions with damage to buildings. Very short period below 0.5 sec. was dominated in most strong ground motions and the 1-2 sec. response which has close relationship with heavy damage to buildings was small, therefore, heavy damage to buildings was not found in spite of high JMA seismic intensity scale.

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We carried out damage investigation around the seismic stations where high JMA seismic intensity scales were recorded in the 2008 Iwate-ken Engan Hokubu Earthquake. We found some minor damage such as small cracks in the wall or damaged glass, but heavy damage to buildings was not found around all the seismic stations. We investigated the correspondence of strong ground motions with damage to buildings. Very short period below 0.5 sec. was dominated in most strong ground motions and the 1-2 sec. response which has close relationship with heavy damage to buildings was small, therefore, heavy damage to buildings was not found in spite of high JMA seismic intensity scale.

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We carried out damage investigation around the seismic stations where high JMA seismic intensity scales were recorded in the 2009 Suruga Bay Earthquake. We found some minor damage such as small damage to the wall or damaged roof tiles, but heavy damage to buildings was not found around all the seismic stations. However, we found many wooden houses with damaged roof tiles. We investigated the correspondence of strong ground motions with damage to buildings. Very short period below 0.5 sec. was dominated in most strong ground motions and the 1-2 sec. response which has close relationship with heavy damage to buildings was small, therefore, heavy damage to buildings was not found in spite of high JMA seismic intensity scale. We gathered quantitative data of damaged roof tiles and investigated relationship between the period region of strong ground motions and damaged roof tiles. We found that the period of about 0.5sec. of strong ground motions had close correlation with damage to roof tiles.

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